| Author | Title | Year | Journal/Proceedings | Reftype | DOI/URL |
|---|---|---|---|---|---|
| van Adel, B. A. & Kelly, J. B. | Kainic acid lesions of the superior olivary complex: effects on sound localization by the albino rat. | 1998 | Behav Neurosci | article | |
| Abstract: The ability of rats to localize sounds in space was determined before and after kainic acid lesions of the superior olivary complex (SOC). Animals were tested with a 45-ms noise burst delivered from loudspeakers on the right or left of midline. Anatomical data showed that the lesions destroyed neurons in SOC while preserving fibers of passage in the trapezoid body and other decussating pathways of the auditory brainstem. Animals with either unilateral or bilateral SOC lesions were impaired in their ability to localize a single noise burst postoperatively. Deficits were also found after unilateral lesions restricted primarily to the lateral superior olive. SOC lesions resulted in an elevation in minimum audible angles for sound localization. | |||||
BibTeX:
@article{Adel1998,
author = {B. A. van Adel and J. B. Kelly},
title = {Kainic acid lesions of the superior olivary complex: effects on sound localization by the albino rat.},
journal = {Behav Neurosci},
year = {1998},
volume = {112},
number = {2},
pages = {432--446}
}
|
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| Aitkin, L. M., Kenyon, C. E. & Philpott, P. | The representation of the auditory and somatosensory systems in the external nucleus of the cat inferior colliculus. | 1981 | J Comp Neurol | article | DOIURL |
| Abstract: Parallel single unit and retrograde tracing experiments were carried out in the anesthetized cat to elucidate the representation of the auditory and somatosensory systems in the external nucleus of the inferior colliculus (ICX). Units responding to tonal stimuli were more commonly encountered in ICX and the adjacent intercollicular area (ICA) than were units with identified tactile receptive fields. Concomitantly, a larger number of retrogradely labeled cells were identified in midbrain auditory structures, following injections of horseradish peroxidase (HRP) into CRX, than were found in the combined dorsal column nuclei. Microelectrode recording revealed that the entire accessible body surface was represented in ICX, and receptive fields of individual units were usually large and mostly located on the contralateral side. HRP-labeled cells were scattered throughout the contralateral cuneate, gracile, and spinal trigeminal nuclei. tations of tone pips. Responses to complex sound were commonly observed. Binaural stimuli influenced the firing of the majority of auditory units. Labeled auditory neurons following ICX injections were found mainly in the inferior colliculus of both sides. Spread of tracer into the central and pericentral nuclei was associated with labeling of many neurons in hind brain auditory structures. Only vague suggestions of somatotopy or tonotopy were observed in the electrophysiological experiments; similarly, no topographical relationship between HRP injection site and locus of retrograde label in a given projecting nucleus could be discerned. Speculations were made, in the light of the dual convergent sensory representation in ICX, about the role of this structure in acoustico-motor mechanisms. | |||||
BibTeX:
@article{Aitkin1981,
author = {L. M. Aitkin and C. E. Kenyon and P. Philpott},
title = {The representation of the auditory and somatosensory systems in the external nucleus of the cat inferior colliculus.},
journal = {J Comp Neurol},
year = {1981},
volume = {196},
number = {1},
pages = {25--40},
url = {http://dx.doi.org/10.1002/cne.901960104},
doi = {http://dx.doi.org/10.1002/cne.901960104}
}
|
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| Alexeenko, N. Y. & Verderevskaya, N. N. | Proprioceptive effects on evoked responses to sounds in the cat auditory cortex. | 1976 | Exp Brain Res | article | |
| Abstract: With a view to analyse the influence of neck proprioceptors on directional hearing, evoked potentials (EPs) to dichotically or monaurally presented clicks were recorded from the auditory cortex of cats under deep Nembutal anaesthesia with their head pointing to the front, and then to the right or to the left side at 45 degrees. The change in the head position produced considerable changes in the amplitude of the two primary EP components and in their thresholds. The changes were of two kinds: either decrease or increase of the amplitude. At symmetrical points of the auditory cortex they went in the same direction. The also appeared in the associative zone with the same sign. With monaurally presented clicks, the change of the side of stimulation for the most part resulted in a reversal of the sign of the proprioceptive effect. Similar proprioceptive influences were recorded when the clicks were presented not through earphones but in an open acoustic field. | |||||
BibTeX:
@article{Alexeenko1976,
author = {N. Y. Alexeenko and N. N. Verderevskaya},
title = {Proprioceptive effects on evoked responses to sounds in the cat auditory cortex.},
journal = {Exp Brain Res},
year = {1976},
volume = {26},
number = {5},
pages = {495--508}
}
|
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| Algazi, V. R., Avendano, C. & Duda, R. O. | Elevation localization and head-related transfer function analysis at low frequencies. | 2001 | J Acoust Soc Am | article | |
| Abstract: Monaural spectral features due to pinna diffraction are the primary cues for elevation. Because these features appear above 3 kHz where the wavelength becomes comparable to pinna size, it is generally believed that accurate elevation estimation requires wideband sources. However, psychoacoustic tests show that subjects can estimate elevation for low-frequency sources. In the experiments reported, random noise bursts low-pass filtered to 3 kHz were processed with individualized head-related transfer functions (HRTFs), and six subjects were asked to report the elevation angle around four cones of confusion. The accuracy in estimating elevation was degraded when compared to a baseline test with wideband stimuli. The reduction in performance was a function of azimuth and was highest in the median plane. However, when the source was located away from the median plane, subjects were able to estimate elevation, often with surprisingly good accuracy. Analysis of the HRTFs reveals the existence of elevation-dependent features at low frequencies. The physical origin of the low-frequency features is attributed primarily to head diffraction and torso reflections. It is shown that simple geometrical approximations and models of the head and torso explain these low-frequency features and the corresponding elevations cues. | |||||
BibTeX:
@article{Algazi2001,
author = {V. R. Algazi and C. Avendano and R. O. Duda},
title = {Elevation localization and head-related transfer function analysis at low frequencies.},
journal = {J Acoust Soc Am},
year = {2001},
volume = {109},
number = {3},
pages = {1110-22}
}
|
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| Algazi, V. R., Duda, R. O., Morrison, R. P. & Thompson, D. M. | The CIPIC HRTF Database [BibTeX] |
2001 | Proceedings of the 2001 IEEE Workshop on Applications of Signal Processing to Audio and Acoustics | inproceedings | |
BibTeX:
@inproceedings{Algazi2001a-CIPIC_Database,
author = {Algazi, V. R. and Duda, R. O. and Morrison, R. P. and Thompson, D. M.},
title = {The CIPIC HRTF Database},
booktitle = {Proceedings of the 2001 IEEE Workshop on Applications of Signal Processing to Audio and Acoustics},
year = {2001},
pages = {99-102}
}
|
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| Asano, F., Suzuki, Y. & Sone, T. | Role of spectral cues in median plane localization | 1990 | J. Acoust. Soc. Am. | article | DOI |
| Abstract: The role of spectral cues in the sound source to ear transfer function in median plane sound localization is investigated in this paper. At first, transfer functions were measured and analyzed. Then, these transfer functions were used in experiments where sounds from a source on the median plane were simulated and presented to subjects through headphones. In these simulation experiments, the transfer functions were smoothed by ARMA models with different degrees of simplification to investigate the role of microscopic and macroscopic patterns in the transfer functions for median plane localization. The results of the study are summarized as follows: (1) For front–rear judgment, information derived from microscopic peaks and dips in the low-frequency region (below 2 kHz) and the macroscopic patterns in the high-frequency region seems to be utilized; (2) for judgment of elevation angle, major cues exist in the high-frequency region above 5 kHz. The information in macroscopic patterns is utilized instead of that in small peaks and dips. | |||||
BibTeX:
@article{Asano1990,
author = {Futoshi Asano and Yoiti Suzuki and Toshio Sone},
title = {Role of spectral cues in median plane localization},
journal = {J. Acoust. Soc. Am.},
year = {1990},
volume = {88},
number = {1},
pages = {159-168},
doi = {http://dx.doi.org/10.1121/1.399963}
}
|
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| Ashmead, D. H., Clifton, R. K. & Perris, E. E. | Precision of Auditory Localization in Human Infants. | 1987 | Developmental Psychology | article | |
| Abstract: The precision of auditory localization in 26- to 30-week-old infants was measured with a test based on the adult minimum audible angle. In this test, the horizontal angle between loudspeakers was varied systematically to determine thresholds for discriminating rightward versus leftward sound displacements. Infants were presented with sounds that shifted from straight ahead to the left or right, and observers judged from the infants' eye and head movements to which side the sound had shifted. From trial to trial, the size of the shift was decreased after correct responding and increased after incorrect responding. Infants discriminated sound displacements of about 19°, considerably less accurate than adult values of 1–2°. These findings are discussed in terms of their methodological implications and the development of sensitivity to information for sound localization. | |||||
BibTeX:
@article{Ashmead1987,
author = {Ashmead, Daniel H. and Clifton, Rachel K. and Perris, Eve E.},
title = {Precision of Auditory Localization in Human Infants.},
journal = {Developmental Psychology},
year = {1987},
volume = {23},
number = {5},
pages = {641-647}
}
|
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| Ashmead, D. H., Wall, R. S., Ebinger, K. A., Eaton, S. B., Snook-Hill, M. M. & Yang, X. | Spatial hearing in children with visual disabilities. | 1998 | Perception | article | |
| Abstract: A study is reported of the effect of early visual experience on the development of auditory space perception. The spatial hearing of thirty-five children with visual disabilities (twenty-two with congenital total blindness) was compared with that of eighteen sighted children and seventeen sighted adults. The tests provided a comprehensive assessment of spatial-hearing ability, including psychophysical estimates of spatial resolution in the horizontal, vertical, and distance dimensions, as well as measures of reaching and walking to the locations of sound sources. The spatial hearing of the children with visual disabilities was comparable to or somewhat better than that of the sighted children and adults. This pattern held even when the group with visual disabilities was restricted to those children with congenital total blindness; in fact, some of those children had exceptionally good spatial hearing. These findings imply that the developmental calibration of human spatial hearing is not dependent on a history of visual experience. It seems likely that this calibration arises from the experience of changes in sound-localization cues arising from self-motion, such as turning the head or walking. As a practical matter, orientation and mobility instructors may reasonably assume that individuals with visual disabilities can use their hearing effectively in day-to-day travel situations. | |||||
BibTeX:
@article{Ashmead1998,
author = {D. H. Ashmead and R. S. Wall and K. A. Ebinger and S. B. Eaton and M. M. Snook-Hill and X. Yang},
title = {Spatial hearing in children with visual disabilities.},
journal = {Perception},
year = {1998},
volume = {27},
number = {1},
pages = {105--122}
}
|
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| Au, W. W. L. & Benoit-Bird, K. J. | Automatic gain control in the echolocation system of dolphins. | 2003 | Nature | article | DOIURL |
| Abstract: In bats and technological sonars, the gain of the receiver is progressively increased with time after the transmission of a signal to compensate for acoustic propagation loss. The current understanding of dolphin echolocation indicates that automatic gain control is not a part of their sonar system. In order to test this understanding, we have performed field measurements of free-ranging echolocating dolphins. Here we show that dolphins do possess an automatic gain control mechanism, but that it is implemented in the transmission phase rather than the receiving phase of a sonar cycle. We find that the amplitude of the dolphins' echolocation signals are highly range dependent; this amplitude increases with increasing target range, R, in a 20 log(R) fashion to compensate for propagation loss. If the echolocation target is a fish school with many sound scatterers, the echoes from the school will remain nearly constant with range as the dolphin closes in on it. This characteristic has the same effect as time-varying gain in bats and technological sonar when considered from a sonar system perspective. | |||||
BibTeX:
@article{Au2003,
author = {Whitlow W L Au and Kelly J Benoit-Bird},
title = {Automatic gain control in the echolocation system of dolphins.},
journal = {Nature},
year = {2003},
volume = {423},
number = {6942},
pages = {861--863},
url = {http://dx.doi.org/10.1038/nature01727},
doi = {http://dx.doi.org/10.1038/nature01727}
}
|
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| Auvray, M., Hanneton, S., Lenay, C. & O'Regan, K. | There is something out there: distal attribution in sensory substitution, twenty years later. | 2005 | J Integr Neurosci | article | |
| Abstract: Sensory substitution constitutes an interesting domain of study to consider the philosopher's classical question of distal attribution: how we can distinguish between a sensation and the perception of an object that causes this sensation. We tested the hypothesis that distal attribution consists of three distinct components: an object, a perceptual space, and a coupling between subjects' movements and stimulation. We equipped sixty participants with a visual-to-auditory substitution device, without any information about it. The device converts the video stream produced by a head-mounted camera into a sound stream. We investigated several experimental conditions: the existence or not of a correlation between movements and resulting stimulation, the direct or indirect manipulation of an object, and the presence of a background environment. Participants were asked to describe their impressions by rating their experiences in terms of seven possible "scenarios". These scenarios were carefully chosen to distinguish the degree to which the participants attributed their sensations to a distal cause. Participants rated the scenarios both before and after they were given the possibility to interrupt the stimulation with an obstacle. We were interested in several questions. Did participants extract laws of co-variation between their movements and resulting stimulation? Did they deduce the existence of a perceptual space originating from this coupling? Did they individuate objects that caused the sensations? Whatever the experimental conditions, participants were able to establish that there was a link between their movements and the resulting auditory stimulation. Detection of the existence of a coupling was more frequent than the inferences of distal space and object. | |||||
BibTeX:
@article{Auvray2005,
author = {Malika Auvray and Sylvain Hanneton and Charles Lenay and Kevin O'Regan},
title = {There is something out there: distal attribution in sensory substitution, twenty years later.},
journal = {J Integr Neurosci},
year = {2005},
volume = {4},
number = {4},
pages = {505--521}
}
|
|||||
| Aytekin, M., Grassi, E., Sahota, M. & Moss, C. | The bat head-related transfer function reveals binaural cues for sound localization in azimuth and elevation | 2004 | J Acoust Soc Am | article | URL |
| Abstract: Directional properties of the sound transformation at the ear of four intact echolocating bats, Eptesicus fuscus, were investigated via measurements of the head-related transfer function (HRTF). Contributions of external ear structures to directional features of the transfer functions were examined by remeasuring the HRTF in the absence of the pinna and tragus. The investigation mainly focused on the interactions between the spatial and the spectral features in the bat HRTF. The pinna provides gain and shapes these features over a large frequency band (20-90 kHz), and the tragus contributes gain and directionality at the high frequencies (60 to 90 kHz). Analysis of the spatial and spectral characteristics of the bat HRTF reveals that both interaural level differences (ILD) and monaural spectral features are subject to changes in sound source azimuth and elevation. Consequently, localization cues for horizontal and vertical components of the sound source location interact. Availability of multiple cues about sound source azimuth and elevation should enhance information to support reliable sound localization. These findings stress the importance of the acoustic information received at the two ears for sound localization of sonar target position in both azimuth and elevation. | |||||
BibTeX:
@article{Aytekin2004,
author = {Aytekin, M. and Grassi, E. and Sahota, M. and Moss, CF.},
title = {The bat head-related transfer function reveals binaural cues for sound localization in azimuth and elevation},
journal = {J Acoust Soc Am},
year = {2004},
volume = {116},
number = {6},
pages = {3594-3605},
url = {http://www.hubmed.org/display.cgi?uids=15658710}
}
|
|||||
| Aytekin, M. & Moss, C. | Interaural Level Difference Based Sound Localization by Bats [BibTeX] |
2004 | Society for Neuroscience, 2004 Annual Meeting. | conference | |
BibTeX:
@conference{Aytekin2004a,
author = {M. Aytekin and C.F. Moss},
title = {Interaural Level Difference Based Sound Localization by Bats},
booktitle = {Society for Neuroscience, 2004 Annual Meeting.},
year = {2004}
}
|
|||||
| Aytekin, M., Simon, J. J. & Moss, C. F. | A sensorry motor approach to sound localization [BibTeX] |
Neural Computation | article | ||
BibTeX:
@article{Aytekin,
author = {Murat Aytekin and Jonathan J. Simon and Cynthia F. Moss},
title = {A sensorry motor approach to sound localization},
journal = {Neural Computation}
}
|
|||||
| Babkoff, H., Sutton, S. & Barris, M. | Binaural interaction of transients: interaural time and intensity asymmetry. [BibTeX] |
1973 | J Acoust Soc Am | article | |
BibTeX:
@article{Babkoff1973,
author = {H. Babkoff and S. Sutton and M. Barris},
title = {Binaural interaction of transients: interaural time and intensity asymmetry.},
journal = {J Acoust Soc Am},
year = {1973},
volume = {53},
number = {4},
pages = {1028--1036}
}
|
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| Bach-y-Rita, P. | Tactile sensory substitution studies. | 2004 | Ann N Y Acad Sci | article | |
| Abstract: Forty years ago a project to explore late brain plasticity was initiated that was to lead into a broad area of sensory substitution studies. The questions at that time were: Can a person who has never seen learn to see as an adult? Is the brain sufficiently plastic to develop an entirely new sensory system? The short answer to both questions is yes, first clearly demonstrated in 1969 ((Bach-y-Rita et al., 1969)). To reach that conclusion, it was first necessary to find a way to get visual information to the brain. That took many years and is still the most challenging aspect of the research and the development of practical sensory substitution and augmentation systems. The sensor array is not a problem: a TV camera for blind persons; an accelerometer for persons with vestibular loss; a microphone for deaf persons. These are common and fully developed devices. The problem is the brain-machine interface (BMI). In this short report, only two substitution systems are discussed, vision and vestibular substitution. | |||||
BibTeX:
@article{Bach-y-Rita2004,
author = {Paul {Bach-y-Rita}},
title = {Tactile sensory substitution studies.},
journal = {Ann N Y Acad Sci},
year = {2004},
volume = {1013},
pages = {83--91}
}
|
|||||
| Bach-y-Rita, P. & Kercel, S. W. | Sensory substitution and the human-machine interface. | 2003 | Trends Cogn Sci | article | |
| Abstract: Recent advances in the instrumentation technology of sensory substitution have presented new opportunities to develop systems for compensation of sensory loss. In sensory substitution (e.g. of sight or vestibular function), information from an artificial receptor is coupled to the brain via a human-machine interface. The brain is able to use this information in place of that usually transmitted from an intact sense organ. Both auditory and tactile systems show promise for practical sensory substitution interface sites. This research provides experimental tools for examining brain plasticity and has implications for perceptual and cognition studies more generally. | |||||
BibTeX:
@article{Bach-y-Rita2003,
author = {{Bach-y-Rita}, Paul and Kercel, Stephen W},
title = {Sensory substitution and the human-machine interface.},
journal = {Trends Cogn Sci},
year = {2003},
volume = {7},
number = {12},
pages = {541--546}
}
|
|||||
| Bajcsy, R. | Active perception [BibTeX] |
1988 | Proceedings of the IEEE | article | DOI |
BibTeX:
@article{Bajcsy1988,
author = {Bajcsy, R},
title = {Active perception},
journal = {Proceedings of the IEEE},
year = {1988},
volume = {76},
number = {8},
pages = {966-1005},
doi = {http://dx.doi.org/10.1109/5.5968}
}
|
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| Bajo, V. M., Nodal, F. R., Bizley, J. K., Moore, D. R. & King, A. J. | The ferret auditory cortex: descending projections to the inferior colliculus. | 2007 | Cereb Cortex | article | DOIURL |
| Abstract: Descending corticofugal projections are thought to play a critical role in shaping the responses of subcortical neurons. Here, we examine the origins and targets of ferret auditory corticocollicular projections. We show that the ectosylvian gyrus (EG), where the auditory cortex is located, can be subdivided into middle, anterior, and posterior regions according to the pattern of cytochrome oxidase staining and immunoreactivity for the neurofilament antibody SMI32. Injection of retrograde tracers in the inferior colliculus (IC) labeled large layer V pyramidal cells throughout the EG and adjacent sulci. Each region of the EG has a different pattern of descending projections. Neurons in the primary auditory fields in the middle EG project to the lateral nucleus (LN) of the ipsilateral IC and bilaterally to the dorsal cortex and dorsal part of the central nucleus (CN). The projection to these dorsomedial regions of the IC is predominantly ipsilateral and topographically organized. The secondary cortical fields in the posterior EG target the same midbrain areas but exclude the CN of the IC. A smaller projection to the ipsilateral LN also arises from the anterior EG, which is the only region of auditory cortex to target tegmental areas surrounding the IC, including the superior colliculus, periaqueductal gray, intercollicular tegmentum, and cuneiform nucleus. This pattern of corticocollicular connectivity is consistent with regional differences in physiological properties and provides another basis for subdividing ferret auditory cortex into functionally distinct areas. | |||||
BibTeX:
@article{Bajo2007,
author = {Victoria M Bajo and Fernando R Nodal and Jennifer K Bizley and David R Moore and Andrew J King},
title = {The ferret auditory cortex: descending projections to the inferior colliculus.},
journal = {Cereb Cortex},
year = {2007},
volume = {17},
number = {2},
pages = {475--491},
url = {http://dx.doi.org/10.1093/cercor/bhj164},
doi = {http://dx.doi.org/10.1093/cercor/bhj164}
}
|
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| Batra, R. & Yin, T. C. T. | Cross correlation by neurons of the medial superior olive: a reexamination. | 2004 | J Assoc Res Otolaryngol | article | DOIURL |
| Abstract: Initial analysis of interaural temporal disparities (ITDs), a cue for sound localization, occurs in the superior olivary complex. The medial superior olive (MSO) receives excitatory input from the left and right cochlear nuclei. Its neurons are believed to be coincidence detectors, discharging when input arrives simultaneously from the two sides. Many current psychophysical models assume a strict version of coincidence, in which neurons of the MSO cross correlate their left and right inputs. However, there have been few tests of this assumption. Here we examine data derived from two earlier studies of the MSO and compare the responses to the output of a computational model. We find that the MSO is not an ideal cross correlator. Ideal cross correlation implies a strict relationship between the precision of phase-locking of the inputs and the range of ITDs to which a neuron responds. This relationship does not appear to be met. Instead, the modeling implies that a neuron responds over a wider range of ITDs than expected from the inferred precision of phase-locking of the inputs. The responses are more consistent with a scheme in which the neuron can also be activated by the input from one side alone. Such activation degrades the tuning of neurons in the MSO to ITDs. | |||||
BibTeX:
@article{Batra2004,
author = {Ranjan Batra and Tom C T Yin},
title = {Cross correlation by neurons of the medial superior olive: a reexamination.},
journal = {J Assoc Res Otolaryngol},
year = {2004},
volume = {5},
number = {3},
pages = {238--252},
url = {http://dx.doi.org/10.1007/s10162-004-4027-4},
doi = {http://dx.doi.org/10.1007/s10162-004-4027-4}
}
|
|||||
| Batteau, D. W. | The role of the pinna in human localization. [BibTeX] |
1967 | Proc R Soc Lond B Biol Sci | article | |
BibTeX:
@article{Batteau1967,
author = {D. W. Batteau},
title = {The role of the pinna in human localization.},
journal = {Proc R Soc Lond B Biol Sci},
year = {1967},
volume = {168},
number = {11},
pages = {158-80},
note = {pdf file exists.}
}
|
|||||
| Bedford, F. L. | Perceptual and cognitive spatial learning. | 1993 | J Exp Psychol Hum Percept Perform | article | |
| Abstract: Ss were taught novel mappings between visual space and motor space with either a variant on a prism adaptation paradigm (Experiments 1 and 2) or a nonperceptual cognitive task (Experiments 3 and 4). First, discrimination training specified that 1 visual location required a new pointing response but another location did not. This led to unusual generalization unlike typical generalization decrement. Second, training at 9 locations specified that 1 location required a new response but that the remaining 8 did not. This simple isolation mapping was unlearnable and instead a flat function fit through all of space. In contrast, for the cognitive paradigm, not only was isolation of one region of space easily learned, it was the preferred pattern of generalization. Implications for perceptual learning, as well as the qualitative distinctions between perceptual and cognitive learning, are discussed. | |||||
BibTeX:
@article{Bedford1993,
author = {F. L. Bedford},
title = {{P}erceptual and cognitive spatial learning.},
journal = {J Exp Psychol Hum Percept Perform},
year = {1993},
volume = {19},
number = {3},
pages = {517--530}
}
|
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| Belkin, M. & Niyogi, P. | Laplacian Eigenmaps for Dimensionality Reduction and Data Representation | 2003 | Neural Computation | article | URL |
| Abstract: One of the central problems in machine learning and pattern recognition is to develop appropriate representations for complex data. We consider the problem of constructing a representation for data lying on a lowdimensional manifold embedded in a high-dimensional space. Drawing on the correspondence between the graph Laplacian, the Laplace Beltrami operator on the manifold, and the connections to the heat equation, we propose a geometrically motivated algorithm for representing the highdimensional data. The algorithm provides a computationally efficient approach to nonlinear dimensionality reduction that has locality-preserving properties and a natural connection to clustering. Some potential applications and illustrative examples are discussed. | |||||
BibTeX:
@article{Belkin2003,
author = {Belkin, Mikhail and Niyogi, Partha},
title = {Laplacian Eigenmaps for Dimensionality Reduction and Data Representation},
journal = {Neural Computation},
year = {2003},
volume = {15},
number = {6},
pages = {1373-1396},
url = {http://search.ebscohost.com/login.aspx?direct=true&db=aph&AN=9737845&site=ehost-live}
}
|
|||||
| Bell, C. C. | Evolution of cerebellum-like structures. | 2002 | Brain Behav Evol | article | |
| Abstract: All vertebrate brains have a cerebellum, and most of them have one or more additional structures that are histologically similar to the cerebellum. The cerebellum-like structures include the medial octavolateral nucleus in most aquatic vertebrates; the dorsal octavolateral nucleus in many aquatic vertebrates with an electrosensory system; the marginal layer of the optic tectum in ray-finned fishes; electrosensory lobes in the few groups of advanced bony fish with an electrosensory system; the rostrolateral nucleus of the thalamus in a few widely scattered groups of bony fish; and the dorsal cochlear nucleus in all mammals except monotremes. All of these structures receive topographically organized sensory input in their deep layers. Purkinje-like cells receive the sensory input near their cell bodies. These cells extend apical dendrites up into the molecular layer where they receive synaptic input from parallel fibers. The cerebellum itself can be included within this characterization by considering the climbing fiber as at least in part a conveyor of sensory information and by recalling that climbing fibers in more basal vertebrates terminate on smooth dendrites close to the soma. Physiological findings from three different systems suggest the hypothesis that cerebellum-like structures remove predictable features from the sensory inflow. Phylogenetic homology can explain the similarities across different taxa for some types of cerebellum-like structures, but similarities within other types cannot be explained in this way. Moreover, phylogenetic homology cannot explain the similarities among different types of cerebellum-like structures. Evolutionary convergence provides the best explanation for all these similarities that cannot be explained by homology. The convergence is almost surely constrained by the availability of a genetic-developmental program for creating cerebellum-like circuitry and by the need within many different systems for the type of information processing that cerebellum-like circuitry can provide. | |||||
BibTeX:
@article{Bell2002,
author = {Curtis C Bell},
title = {Evolution of cerebellum-like structures.},
journal = {Brain Behav Evol},
year = {2002},
volume = {59},
number = {5-6},
pages = {312--326}
}
|
|||||
| Bell, C. C. | Memory-based expectations in electrosensory systems. | 2001 | Curr Opin Neurobiol | article | |
| Abstract: Adaptive processing of electrosensory information occurs in the cerebellum-like structures of three distinct groups of fish. Associations within each of these structures result in the generation of negative images of predictable features of the sensory inflow. Addition of these negative images to the actual inflow removes the predictable features, allowing the unpredictable, information-rich sensory signals to stand out. Evidence from all three groups of fish indicates that the negative images are mediated by plasticity at parallel fiber synapses. | |||||
BibTeX:
@article{Bell2001,
author = {C. C. Bell},
title = {Memory-based expectations in electrosensory systems.},
journal = {Curr Opin Neurobiol},
year = {2001},
volume = {11},
number = {4},
pages = {481--487}
}
|
|||||
| Bell, J. L. | Continuity and Infinitesimals [BibTeX] |
Fall 2005 | The Stanford Encyclopedia of Philosophy | incollection | URL |
BibTeX:
@incollection{BellFall2005,
author = {John L. Bell},
title = {Continuity and Infinitesimals},
booktitle = {The Stanford Encyclopedia of Philosophy},
year = {Fall 2005},
url = {http://plato.stanford.edu/archives/fall2005/entries/continuity/}
}
|
|||||
| Beranek, L. L. | Acoustics [BibTeX] |
1988 | book | ||
BibTeX:
@book{Beranek1988,
author = {L. L. Beranek},
title = {Acoustics},
publisher = {the American Institude of Physics},
year = {1988},
note = {Published for the Acoustical Society of America by}
}
|
|||||
| Bergan, J. F., Ro, P., Ro, D. & Knudsen, E. I. | Hunting increases adaptive auditory map plasticity in adult barn owls. | 2005 | J Neurosci | article | DOIURL |
| Abstract: The optic tectum (OT) of barn owls contains topographic maps of auditory and visual space. Barn owls reared with horizontally displacing prismatic spectacles (prisms) acquire a novel auditory space map in the OT that restores alignment with the prismatically displaced visual map. Although juvenile owls readily acquire alternative maps of auditory space as a result of experience, this plasticity is reduced greatly in adults. We tested whether hunting live prey, a natural and critically important behavior for barn owls, increases auditory map plasticity in adult owls. Two groups of naive adult owls were fit with prisms. The first group was fed dead mice during 10 weeks of prism experience, while the second group was required to hunt live prey for an identical period of time. When the owls hunted live prey, auditory maps shifted substantially farther (five times farther, on average) and the consistency of tuning curve shifts within each map increased. Only a short period of time in each day, during which the two groups experienced different conditions, accounts for this effect. In addition, increased map plasticity correlated with behavioral improvements in the owls' ability to strike and capture prey. These results indicate that the experience of hunting dramatically increases adult adaptive plasticity in this pathway. | |||||
BibTeX:
@article{Bergan2005_Hunting_plasticity,
author = {Joseph F. Bergan and Peter Ro and Daniel Ro and Eric I. Knudsen},
title = {Hunting increases adaptive auditory map plasticity in adult barn owls.},
journal = {J Neurosci},
year = {2005},
volume = {25},
number = {42},
pages = {9816--9820},
url = {http://dx.doi.org/10.1523/JNEUROSCI.2533-05.2005},
doi = {http://dx.doi.org/10.1523/JNEUROSCI.2533-05.2005}
}
|
|||||
| Biel, L. & Wide, P. | Active perception for autonomous sensor systems [BibTeX] |
2000 | Instrumentation & Measurement Magazine, IEEE | article | DOI |
BibTeX:
@article{Biel2000,
author = {Biel, L. and Wide, P.},
title = {Active perception for autonomous sensor systems},
journal = {Instrumentation \& Measurement Magazine, IEEE},
year = {2000},
volume = {3},
number = {4},
pages = {27-30},
doi = {http://dx.doi.org/10.1109/5289.887457}
}
|
|||||
| Binns, K. E., Grant, S., Withington, D. J. & Keating, M. J. | A topographic representation of auditory space in the external nucleus of the inferior colliculus of the guinea-pig. | 1992 | Brain Res | article | |
| Abstract: The possibility that the external nucleus of the inferior colliculus (ICX) of the pigmented guinea-pig contains a map of auditory space has been investigated. Auditory stimuli consisted of broad-band sound delivered under free-field anechoic conditions from a range of positions around the animal's azimuthal axis. The responses of clusters of neurons in the ICX to threshold and to near-threshold stimuli displayed sharp spatial tuning. The responses recorded from rostral ICX revealed a preference for auditory stimuli in the anterior field while more caudal neurons preferentially responded to sounds presented in the posterior field. Neurons at intermediate points, along the rostro-caudal axis of the nucleus, displayed preferences for sound stimuli in appropriately intermediate field positions along the contralateral azimuthal axis. At higher stimulus intensities the spatial tuning of the responses decreased, but the optimal direction of preference was usually retained. The contribution of binaural processing to auditory spatial tuning was evident, since unilateral cochlea ablation destroyed the spatial tuning at higher stimulus intensities. The results presented provide the first evidence that a topographically ordered representation of the contralateral auditory azimuth is present in the ICX of a mammal. | |||||
BibTeX:
@article{Binns1992,
author = {K. E. Binns and S. Grant and D. J. Withington and M. J. Keating},
title = {A topographic representation of auditory space in the external nucleus of the inferior colliculus of the guinea-pig.},
journal = {Brain Res},
year = {1992},
volume = {589},
number = {2},
pages = {231--242}
}
|
|||||
| Binns, K. E., Withington, D. J. & Keating, M. J. | The developmental emergence of the representation of auditory azimuth in the external nucleus of the inferior colliculus of the guinea-pig: the effects of visual and auditory deprivation. | 1995 | Brain Res Dev Brain Res | article | |
| Abstract: A topographic representation of the auditory azimuth has been described in the external nucleus of the inferior colliculus (ICX) of the guinea-pig [3]. This representation is characterized by directional multi-unit responses, at threshold stimulation intensities, with directional preferences organized in such a way as to represent the auditory azimuth along the rostro-caudal axis of the ICX. The following paper considers the emergence of that map and the role of developmental experience in its elaboration. Multi-unit responses to free-field broad-band auditory stimuli were recorded in the ICX. At threshold stimulation intensities, multi-unit receptive fields (MURFs) obtained from younger animals showed the same discrete spatial tuning as found in MURFs from animals older than 35 DAB (days after birth). However, a normal adult topographic representation was not present until animals were at least 30-32 DAB. Visual deprivation, by dark-rearing from birth until mapping (at 35-43 DAB), had no obvious detrimental effects on auditory receptive field size or topographic order in the ICX. Auditory deprivation was achieved by rearing animals in an environment of continuous omnidirectional noise from birth until mapping (47-53 DAB). Following auditory deprivation, receptive fields remained relatively discrete, but no correlation between rostro-caudal position of the recording site and the angle of the best response was observed. Thus, the representation of auditory azimuth in the ICX appears to be unperturbed by developmental visual deprivation but is susceptible to developmental auditory deprivation. | |||||
BibTeX:
@article{Binns1995,
author = {K. E. Binns and D. J. Withington and M. J. Keating},
title = {The developmental emergence of the representation of auditory azimuth in the external nucleus of the inferior colliculus of the guinea-pig: the effects of visual and auditory deprivation.},
journal = {Brain Res Dev Brain Res},
year = {1995},
volume = {85},
number = {1},
pages = {14--24}
}
|
|||||
| Bizley, J. K., Nodal, F. R., Parsons, C. H. & King, A. J. | Role of auditory cortex in sound localization in the midsagittal plane. | 2007 | J Neurophysiol | article | DOIURL |
| Abstract: Although the auditory cortex is known to be essential for normal sound localization in the horizontal plane, its contribution to vertical localization has not so far been examined. In this study, we measured the acuity with which ferrets could discriminate between two speakers in the midsagittal plane before and after silencing activity bilaterally in the primary auditory cortex (A1). This was achieved either by subdural placement of Elvax implants containing the GABA(A) receptor agonist muscimol or by making aspiration lesions after determining the approximate location of A1 electrophysiologically. Psychometric functions and minimum audible angles were measured in the upper hemifield for 500-, 200-, and 40-ms noise bursts. Muscimol-Elvax inactivation of A1 produced a small but significant deficit in the animals' ability to localize brief (40-ms) sounds, which was reversed after removal of the Elvax implants. A similar deficit in vertical localization was observed after bilateral aspiration lesions of A1, whereas performance at longer sound durations was unaffected. Another group of ferrets received larger lesions, encompassing both primary and nonprimary auditory cortical areas, and showed a greater deficit with performance being impaired for long- and short-duration (500- and 40-ms, respectively) stimuli. These data suggest that the integrity of the auditory cortex is required to successfully utilize spectral localization cues, which are thought to provide the basis for vertical localization, and that multiple cortical fields, including A1, contribute to this task. | |||||
BibTeX:
@article{Bizley2007,
author = {Jennifer K Bizley and Fernando R Nodal and Carl H Parsons and Andrew J King},
title = {Role of auditory cortex in sound localization in the midsagittal plane.},
journal = {J Neurophysiol},
year = {2007},
volume = {98},
number = {3},
pages = {1763--1774},
url = {http://dx.doi.org/10.1152/jn.00444.2007},
doi = {http://dx.doi.org/10.1152/jn.00444.2007}
}
|
|||||
| Blakemore, S. J., Frith, C. D. & Wolpert, D. M. | The cerebellum is involved in predicting the sensory consequences of action. | 2001 | Neuroreport | article | |
| Abstract: We used H2(15)O PET to examine neural responses to parametrically varied degrees of discrepancy between the predicted and actual sensory consequences of movement. Subjects used their right hand to move a robotic arm. The motion of this robotic arm determined the position of a second foam-tipped robotic arm, which made contact with the subject's left palm. Using this robotic interface, computer controlled delays were introduced between the movement of the right hand and the tactile stimulation on the left. Activity in the right lateral cerebellar cortex showed a positive correlation with delay. These results suggest the cerebellum is involved in signalling the sensory discrepancy between the predicted and actual sensory consequences of movements. | |||||
BibTeX:
@article{Cerebellum_sensory_consequences,
author = {S. J. Blakemore and C. D. Frith and D. M. Wolpert},
title = {The cerebellum is involved in predicting the sensory consequences of action.},
journal = {Neuroreport},
year = {2001},
volume = {12},
number = {9},
pages = {1879--1884}
}
|
|||||
| Blauert, J. | Spatial Hearing [BibTeX] |
1997 | book | ||
BibTeX:
@book{Blauert1997,
author = {J. Blauert},
title = {Spatial Hearing},
publisher = {MIT Press, Cambridge, MA},
year = {1997}
}
|
|||||
| Bloom, P. J. | Creating source elevation illusions by spectral manipulations [BibTeX] |
1977 | J. Audio Eng. Soc. | article | |
BibTeX:
@article{Bloom1977,
author = {P. J Bloom},
title = {Creating source elevation illusions by spectral manipulations},
journal = {J. Audio Eng. Soc.},
year = {1977},
volume = {25},
pages = {560-565}
}
|
|||||
| BLUM, H. F. | Photoorientation and the tropism theory. [BibTeX] |
1954 | Q Rev Biol | article | |
BibTeX:
@article{BLUM1954,
author = {H. F. BLUM},
title = {{P}hotoorientation and the tropism theory.},
journal = {Q Rev Biol},
year = {1954},
volume = {29},
number = {4},
pages = {307--321}
}
|
|||||
| Bompas, A. & O'Regan, J. K. | More evidence for sensorimotor adaptation in color perception. | 2006 | J Vis | article | DOIURL |
| Abstract: Sensorimotor adaptation can be defined as a perceptual adaptation whose effects depend on the occurrence and nature of the performed motor actions. Examples of sensorimotor adaptation can be found in the literature on prisms concerning several space-related attributes like orientation, curvature, and size. In this article, we show that sensorimotor adaptation can be obtained for color, as a consequence of the introduction of a new sensorimotor contingency between eye movements and color changes. In an adaptation phase, trials involved the successive presentation of two patches, first on the left, and then on the right or the opposite. The left patch being always red and the right patch green, a correlation is introduced between left-right (respectively right-left) eye saccades and red-green (respectively green-red) color change. After 40 min of adaptation, when two yellow patches are successively presented on each side of the screen, the chromaticity of the left and right patches need respectively to be shifted toward the chromaticity of the red and green adaptation patches for subjective equality to be obtained. When the eyes are kept fixed during the adaptation stage, creating a strong nonhomogeneity in retinal adaptation, no effect is found. This ensures that, if present, adaptation at a given retinal location cannot explain the present effect. A third experiment shows a dependency of the effect on the eyes' saccadic movements and not on the position on the screen, that is, on the position of the eyes in the orbits. These results argue for the involvement of sensorimotor mechanisms in color perception. The relation of these experimental findings toward a sensorimotor theory of color perception is discussed. | |||||
BibTeX:
@article{Bompas2006,
author = {Aline Bompas and J. Kevin O'Regan},
title = {More evidence for sensorimotor adaptation in color perception.},
journal = {J Vis},
year = {2006},
volume = {6},
number = {2},
pages = {145--153},
url = {http://dx.doi.org/10.1167/6.2.5},
doi = {http://dx.doi.org/10.1167/6.2.5}
}
|
|||||
| Bompas, A. & O'Regan, J. K. | Evidence for a role of action in colour perception. | 2006 | Perception | article | |
| Abstract: Action is not usually considered to play a role in colour perception. However, sensorimotor theories of perception (eg O'Regan and Noë, 2001 Behavior and Brain Science 24 939-1011) suggest that, on the contrary, the transformations created by action in the sensory input are a necessary condition for all perception. In the case of colour vision, eye movements may explain how a retina with significant irregularities in resolution and cone arrangement (Roorda and Williams, 1999 Nature 397 520-522) could permit the perception of a richly coloured world (Clark and O'Regan, 2000 15th International Conference on Pattern Recognition volume 2: Pattern Recognition and Neural Networks pp 503-506; Skaff et al, 2002 16th International Conference on Pattern Recognition volume 2, pp 681-684). We provide evidence that perception of colour is modified when an artificial coupling is introduced linking eye movements and colour changes. After 40 min of wearing left-field-blue/right-field-yellow spectacles, observers' colour vision adapts so that, after removing the spectacles, white patches seem to become bluer when the eyes move rightwards and yellower when the eyes move leftwards. This induced dependence of colour perception on the direction of eye saccade is shown to be related to the amount of eye movements during exposure. This result, which cannot be explained either by retinal adaptation, or by a conditioned association between colour and side, constitutes first clear evidence for a role of eye movements in perceived colour and argues for the involvement in colour perception of neural mechanisms continuously tuned to sensorimotor contingencies. | |||||
BibTeX:
@article{Bompas2006a,
author = {Aline Bompas and J. Kevin O'Regan},
title = {Evidence for a role of action in colour perception.},
journal = {Perception},
year = {2006},
volume = {35},
number = {1},
pages = {65--78}
}
|
|||||
| Bower, T. G. R. | Rational Infant: learning in infancy [BibTeX] |
1989 | book | ||
BibTeX:
@book{Bower1989,
author = {T. G. R. Bower},
title = {Rational Infant: learning in infancy},
publisher = {W. H. Freeman and Company, New York},
year = {1989}
}
|
|||||
| Brainard, M. S., Knudsen, E. I. & Esterly, S. D. | Neural derivation of sound source location: resolution of spatial ambiguities in binaural cues. | 1992 | J Acoust Soc Am | article | |
| Abstract: Cues for sound localization are inherently spatially ambiguous. Nevertheless, most neurons in the barn owl's optic tectum (superior colliculus) have receptive fields for broadband noise stimuli that are restricted to a single region of space. This study characterizes the spatial ambiguities associated with two important sets of localization cues, interaural level differences (ILDs) and interaural phase differences (IPDs), and describes how information is integrated within and across frequencies to resolve these ambiguities. The auditory receptive fields of neurons in the optic tectum were measured with free-field sounds presented from a movable loudspeaker. In contrast to the single regions typical for broadband receptive fields, receptive fields for tonal stimuli usually included additional discrete regions of space (accessory fields). Based on acoustic measurements of ILD and IPD cues made in the external ear canals, it was shown that accessory fields corresponded to locations from which sound sources produced ILD and IPD values that were approximately the same as those arising from the broadband receptive field. In addition, accessory fields had inhibitory surrounds, corresponding to locations from which sound sources produced substantially different combinations of ILD and IPD values. Where an accessory field for one frequency overlapped with the inhibitory surround of a second frequency, an excitatory response to the first frequency could be reduced or eliminated by addition of the second frequency. Because tonal receptive fields for different frequencies always overlapped in the region of the broadband receptive field but tended not to overlap elsewhere, this integration of excitation and inhibition can account for the restriction of broadband receptive fields to a single region of space. | |||||
BibTeX:
@article{Brainard1992,
author = {M. S. Brainard and E. I. Knudsen and S. D. Esterly},
title = {{N}eural derivation of sound source location: resolution of spatial ambiguities in binaural cues.},
journal = {J Acoust Soc Am},
year = {1992},
volume = {91},
number = {2},
pages = {1015--1027}
}
|
|||||
| Bronkhorst, A. W. | Localization of real and virtual sound sources | 1995 | The Journal of the Acoustical Society of America | article | URL |
| Abstract: Localization of real and virtual sound sources was studied using two tasks. In the first task, subjects had to turn their head while the sound was continuously on and press a button when they thought they faced the source. In the second task, the source only produced a short sound and the subjects had to indicate, by pressing one of eight buttons, in which quadrant the source was located, and whether it was located above or below the horizontal plane. Virtual sound sources were created using head-related transfer functions (HRTFs), measured with probe microphones placed in the ear canals of the subjects. Sound stimuli were harmonic signals with a fundamental frequency of 250 Hz and an upper frequency ranging from 4 to 15 kHz. Results, obtained from eight subjects, show that localization performance for real and virtual sources was similar in both tasks, provided that the stimuli did not contain frequencies above 7 kHz. When frequencies up to 15 kHz were included, performance for virtual sources was, in general, poorer than for real sources. Differences between results for real and virtual sources were relatively small in the first task, provided that individualized HRTFs were used to create the virtual sources, but quite large (a factor of 2) in the second task. The differences were probably caused by a distortion of high-frequency spectral cues in the HRTFs, introduced by the probe microphone measurement in the ear canal. | |||||
BibTeX:
@article{bronkhorst:2542,
author = {Adelbert W. Bronkhorst},
title = {Localization of real and virtual sound sources},
journal = {The Journal of the Acoustical Society of America},
publisher = {ASA},
year = {1995},
volume = {98},
number = {5},
pages = {2542-2553},
url = {http://link.aip.org/link/?JAS/98/2542/1}
}
|
|||||
| Brown, C. H. & May, B. J. | Sound Source Localization [BibTeX] |
2003 | inbook | ||
BibTeX:
@inbook{Brown2003,
author = {Brown, C. H. and May, B. J.},
title = {Sound Source Localization},
publisher = {Springer-Verlag},
year = {2003},
pages = {124-177}
}
|
|||||
| Brungart, D. S., Durlach, N. I. & Rabinowitz, W. M. | Auditory localization of nearby sources. II. Localization of a broadband source. | 1999 | J Acoust Soc Am | article | |
| Abstract: Although many researchers have examined auditory localization for relatively distant sound sources, little is known about the spatial perception of nearby sources. In the region within 1 m of a listener's head, defined as the "proximal region," the interaural level difference increases dramatically as the source approaches the head, while the interaural time delay is roughly independent of distance. An experiment has been performed to evaluate proximal-region localization performance. An auditory point source was moved to a random position within 1 m of the subject's head, and the subject responded by pointing to the perceived location of the sound with an electromagnetic position sensor. The overall angular error (17 degrees) was roughly comparable to previously measured results in distal-region experiments. Azimuth error increased slightly as the sound source approached the head, but elevation performance was essentially independent of source distance. Distance localization performance was generally better than has been reported in distal-region experiments and was strongly dependent on azimuth, with the stimulus-response correlation ranging from 0.85 to the side of the head to less than 0.4 in the median plane. The results suggest that the enlarged binaural difference cues found in the head-related transfer function (HRTF) for nearby sources are important to auditory distance perception in the proximal region. | |||||
BibTeX:
@article{Brungart1999,
author = {D. S. Brungart and N. I. Durlach and W. M. Rabinowitz},
title = {Auditory localization of nearby sources. {II}. {L}ocalization of a broadband source.},
journal = {J Acoust Soc Am},
year = {1999},
volume = {106},
number = {4 Pt 1},
pages = {1956-68}
}
|
|||||
| Budinger, E., Heil, P., Hess, A. & Scheich, H. | Multisensory processing via early cortical stages: Connections of the primary auditory cortical field with other sensory systems. | 2006 | Neuroscience | article | DOIURL |
| Abstract: It is still a popular view that primary sensory cortices are unimodal, but recent physiological studies have shown that under certain behavioral conditions primary sensory cortices can also be activated by multiple other modalities. Here, we investigate the anatomical substrate, which may underlie multisensory processes at the level of the primary auditory cortex (field AI), and which may, in turn, enable AI to influence other sensory systems. We approached this issue by means of the axonal transport of the sensitive bidirectional neuronal tracer fluorescein-labeled dextran which was injected into AI of Mongolian gerbils (Meriones unguiculatus). Of the total number of retrogradely labeled cell bodies (i.e. cells of origin of direct projections to AI) found in non-auditory sensory and multisensory brain areas, approximately 40 were in cortical areas and 60 in subcortical structures. Of the cell bodies in the cortical areas about 82 were located in multisensory cortex, viz., the dorsoposterior and ventroposterior, posterior parietal cortex, the claustrum, and the endopiriform nucleus, 10 were located in the primary somatosensory cortex (hindlimb and trunk region), and 8 in secondary visual cortex. The cortical regions with retrogradely labeled cells also contained anterogradely labeled axons and their terminations, i.e. they are also target areas of direct projections from AI. In addition, the primary olfactory cortex was identified as a target area of projections from AI. The laminar pattern of corticocortical connections suggests that AI receives primarily cortical feedback-type inputs and projects in a feedforward manner to its target areas. Of the labeled cell bodies in the subcortical structures, approximately 90 were located in multisensory thalamic, 4 in visual thalamic, and 6 in multisensory lower brainstem structures. At subcortical levels, we observed a similar correspondence of retrogradely labeled cells and anterogradely labeled axons and terminals in visual (posterior limitans thalamic nucleus) and multisensory thalamic nuclei (dorsal and medial division of the medial geniculate body, suprageniculate nucleus, posterior thalamic cell group, zona incerta), and in the multisensory nucleus of the brachium of the inferior colliculus. Retrograde, but not anterograde, labeling was found in the multisensory pontine reticular formation, particularly in the reticulotegmental nucleus of the pons. Conversely, anterograde, but no retrograde, labeling was found in the visual laterodorsal and lateroposterior thalamic nuclei, in the multisensory peripeduncular, posterior intralaminar, and reticular thalamic nuclei, as well as in the multisensory superior and pericentral inferior colliculi (including cuneiform and sagulum nucleus), pontine nuclei, and periaqueductal gray. Our study supports the notion that AI is not merely involved in the analysis of auditory stimulus properties but also in processing of other sensory and multisensory information. Since AI is directly connected to other primary sensory cortices (viz. the somatosensory and olfactory ones) multisensory information is probably also processed in these cortices. This suggests more generally, that primary sensory cortices may not be unimodal. | |||||
BibTeX:
@article{Budinger2006,
author = {E. Budinger and P. Heil and A. Hess and H. Scheich},
title = {Multisensory processing via early cortical stages: Connections of the primary auditory cortical field with other sensory systems.},
journal = {Neuroscience},
year = {2006},
volume = {143},
number = {4},
pages = {1065--1083},
url = {http://dx.doi.org/10.1016/j.neuroscience.2006.08.035},
doi = {http://dx.doi.org/10.1016/j.neuroscience.2006.08.035}
}
|
|||||
| Buisseret, P., Gary-Bobo, E. & Imbert, M. | Ocular motility and recovery of orientational properties of visual cortical neurones in dark-reared kittens. [BibTeX] |
1978 | Nature | article | |
BibTeX:
@article{Buisseret1978,
author = {P. Buisseret and E. Gary-Bobo and M. Imbert},
title = {Ocular motility and recovery of orientational properties of visual cortical neurones in dark-reared kittens.},
journal = {Nature},
year = {1978},
volume = {272},
number = {5656},
pages = {816--817}
}
|
|||||
| Bulkin, D. A. & Groh, J. M. | Seeing sounds: visual and auditory interactions in the brain. | 2006 | Curr Opin Neurobiol | article | DOIURL |
| Abstract: Objects and events can often be detected by more than one sensory system. Interactions between sensory systems can offer numerous benefits for the accuracy and completeness of the perception. Recent studies involving visual-auditory interactions have highlighted the perceptual advantages of combining information from these two modalities and have suggested that predominantly unimodal brain regions play a role in multisensory processing. | |||||
BibTeX:
@article{Bulkin2006,
author = {David A Bulkin and Jennifer M Groh},
title = {Seeing sounds: visual and auditory interactions in the brain.},
journal = {Curr Opin Neurobiol},
year = {2006},
volume = {16},
number = {4},
pages = {415--419},
url = {http://dx.doi.org/10.1016/j.conb.2006.06.008},
doi = {http://dx.doi.org/10.1016/j.conb.2006.06.008}
}
|
|||||
| Bundy, R. S. | Discrimination of sound localization cues in young infants. | 1980 | Child Dev | article | |
| Abstract: Infants 8 and 16 weeks old were tested in a visual fixation paradigm for the detection and use of sound localization cues. The effects of changes in both interaural intensity and interaural arrival time were assessed independently. For each trial, sounds were presented at the same time as visual displays located on both sides of the infant. The first eye movement and total looking time to each of the visual displays were noted by corneal reflection. Following a series of trials in which the apparent location of the sound was on 1 side, the apparent location was changed for a series of test trials. Neither age group responded with appropriate directional eye movements. The older infants did, however, show generally increased looking time on the test trials for both binaural cues. The 8-week-olds responded on test trials only when the interaural arrival time was changed. The data indicate that both binaural cues can be detected by 16-week-old infants although interaural arrival time was more salient in this paradigm. | |||||
BibTeX:
@article{Bundy1980,
author = {R. S. Bundy},
title = {Discrimination of sound localization cues in young infants.},
journal = {Child Dev},
year = {1980},
volume = {51},
number = {1},
pages = {292--294}
}
|
|||||
| Burnett, L. R., Stein, B. E., Chaponis, D. & Wallace, M. T. | Superior colliculus lesions preferentially disrupt multisensory orientation. | 2004 | Neuroscience | article | DOIURL |
| Abstract: The general involvement of the superior colliculus (SC) in orientation behavior and the striking parallels between the multisensory responses of SC neurons and overt orientation behaviors have led to assumptions that these neural and behavioral changes are directly linked. However, deactivation of two areas of cortex which also contain multisensory neurons, the anterior ectosylvian sulcus and rostral lateral suprasylvian sulcus have been shown to eliminate multisensory orientation behaviors, suggesting that this behavior may not involve the SC. To determine whether the SC contributes to this behavior, cats were tested in a multisensory (i.e. visual-auditory) orientation task before and after excitotoxic lesions of the SC. For unilateral SC lesions, modality-specific (i.e. visual or auditory) orientation behaviors had returned to pre-lesion levels after several weeks of recovery. In contrast, the enhancements and depressions in behavior normally seen with multisensory stimuli were severely compromised in the contralesional hemifield. No recovery of these behaviors was observed within the 6 month testing period. Immunohistochemical labeling of the SC revealed a preferential loss of parvalbumin-immunoreactive pyramidal neurons in the intermediate layers, a presumptive multisensory population that targets premotor areas of the brainstem and spinal cord. These results highlight the importance of the SC for multisensory behaviors, and suggest that the multisensory orientation deficits produced by cortical lesions are a result of the loss of cortical influences on multisensory SC neurons. | |||||
BibTeX:
@article{Burnett2004,
author = {L. R. Burnett and B. E. Stein and D. Chaponis and M. T. Wallace},
title = {Superior colliculus lesions preferentially disrupt multisensory orientation.},
journal = {Neuroscience},
year = {2004},
volume = {124},
number = {3},
pages = {535--547},
url = {http://dx.doi.org/10.1016/j.neuroscience.2003.12.026},
doi = {http://dx.doi.org/10.1016/j.neuroscience.2003.12.026}
}
|
|||||
| Butler, R. A. & Flannery, R. | The spatial attributes of stimulus frequency and their role in monaural localization of sound in the horizontal plane. [BibTeX] |
1980 | Percept Psychophys | article | |
BibTeX:
@article{Butler1980,
author = {R. A. Butler and R. Flannery},
title = {The spatial attributes of stimulus frequency and their role in monaural localization of sound in the horizontal plane.},
journal = {Percept Psychophys},
year = {1980},
volume = {28},
number = {5},
pages = {449--457}
}
|
|||||
| Butler, R. A. & Helwig, C. C. | The spatial attributes of stimulus frequency in the median sagittal plane and their role in sound localization. | 1983 | Am J Otolaryngol | article | |
| Abstract: Stimulus cues used to locate sounds in the median sagittal plane were investigated. Listeners first were required to report the location of noise bands 1.0 kHz wide whose center frequencies ranged from 4.0 through 14.0 kHz. It was found that the apparent locations of the stimuli depended on their frequency compositions, not their places of origin. As the center frequency was increased from 4.0 to about 12.0 kHz, the apparent location of the sound moved from in front of the subject to the rear. Then, at center frequencies of around 13.0 kHz, the sounds again appeared to come from the front. The authors infer that different frequency regions within the sound's spectrum possess specific spatial referents along the median sagittal plane. When the bandwidth was increased to 4.0 kHz, listeners could locate the stimuli with reasonable proficiency only for the sectors of the median sagittal plane that were represented by the spatial referents inherent in the frequency composition of the stimulus. Finally, a stimulus comprising all audible frequencies above 4.0 kHz could be located proficiently, and it is concluded that this sound, unlike the others, contained all spatial referents for the median sagittal plane, hence the superior performance on the localization task. | |||||
BibTeX:
@article{Butler1983,
author = {R. A. Butler and C. C. Helwig},
title = {The spatial attributes of stimulus frequency in the median sagittal plane and their role in sound localization.},
journal = {Am J Otolaryngol},
year = {1983},
volume = {4},
number = {3},
pages = {165--173}
}
|
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| Calford, M. B. & Pettigrew, J. D. | Frequency dependence of directional amplification at the cat's pinna. | 1984 | Hear Res | article | |
| Abstract: We examined in detail the effects of changing stimulus frequency upon the inclination of the acoustical axis of the pinna and upon the solid angle (area) subtended by isoamplification contours. We measured the relative sound pressure level difference between points on a 1 m radius, coordinate sphere using the cochlear microphonic as an indicator of tympanic sound pressure. The inclination of the acoustical axis for a given frequency was found to vary with the posture of the pinna, and with the pinna in a drooped position (following midline incision) there was a frequency spreading of axial positions such that high frequency axes were inclined progressively more laterally. However, with the pinna in an upright posture the axes for all frequencies tested were relatively tightly clustered. Alternative models for sound localization can be formulated to suit either situation, but it seems likely that the cat can use the frequency spreading effect of its pinna sound transformation as a cue to location. The pinna becomes more directional at higher frequencies, and this is clearly shown when the solid angle of isoamplification contours is plotted against frequency. The inverse relationship formed was shown to be closely matched by a model based upon diffraction by the outer dimension of the pinna. | |||||
BibTeX:
@article{Calford1984,
author = {M. B. Calford and J. D. Pettigrew},
title = {Frequency dependence of directional amplification at the cat's pinna.},
journal = {Hear Res},
year = {1984},
volume = {14},
number = {1},
pages = {13--19}
}
|
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| Campbell, R. A. A., Doubell, T. P., Nodal, F. R., Schnupp, J. W. H. & King, A. J. | Interaural timing cues do not contribute to the map of space in the ferret superior colliculus: a virtual acoustic space study. | 2006 | J Neurophysiol | article | DOIURL |
| Abstract: In this study, we used individualized virtual acoustic space (VAS) stimuli to investigate the representation of auditory space in the superior colliculus (SC) of anesthetized ferrets. The VAS stimuli were generated by convolving broadband noise bursts with each animal's own head-related transfer function and presented over earphones. Comparison of the amplitude spectra of the free-field and VAS signals and of the spatial receptive fields of neurons recorded in the inferior colliculus with each form of stimulation confirmed that the VAS provided an accurate simulation of sounds presented in the free field. Units recorded in the deeper layers of the SC responded predominantly to virtual sound directions within the contralateral hemifield. In most cases, increasing the sound level resulted in stronger spike discharges and broader spatial receptive fields. However, the preferred sound directions, as defined by the direction of the centroid vector, remained largely unchanged across different levels and, as observed in previous free-field studies, varied topographically in azimuth along the rostrocaudal axis of the SC. We also examined the contribution of interaural time differences (ITDs) to map topography by digitally manipulating the VAS stimuli so that ITDs were held constant while allowing other spatial cues to vary naturally. The response properties of the majority of units, including centroid direction, remained unchanged with fixed ITDs, indicating that sensitivity to this cue is not responsible for tuning to different sound directions. These results are consistent with previous data suggesting that sensitivity to interaural level differences and spectral cues provides the basis for the map of auditory space in the mammalian SC. | |||||
BibTeX:
@article{Campbell2006,
author = {Robert A A Campbell and Timothy P Doubell and Fernando R Nodal and Jan W H Schnupp and Andrew J King},
title = {Interaural timing cues do not contribute to the map of space in the ferret superior colliculus: a virtual acoustic space study.},
journal = {J Neurophysiol},
year = {2006},
volume = {95},
number = {1},
pages = {242--254},
url = {http://dx.doi.org/10.1152/jn.00827.2005},
doi = {http://dx.doi.org/10.1152/jn.00827.2005}
}
|
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| Campos, J., Anderson, D., Barbu-Roth, M., Hubbard, E., Hertenstein, M. & Witherington, D. | Travel Broadens the mind [BibTeX] |
2000 | Infancy | article | |
BibTeX:
@article{Campos2000,
author = {J. Campos and D. Anderson and M. Barbu-Roth and E. Hubbard and M. Hertenstein and Witherington, D.},
title = {Travel Broadens the mind},
journal = {Infancy},
year = {2000},
volume = {1},
pages = {149-219}
}
|
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| Carlile, S. | The auditory periphery of the ferret. I: Directional response properties and the pattern of interaural level differences. | 1990 | J Acoust Soc Am | article | |
| Abstract: The transformations of sound by the auditory periphery of the ferret have been investigated using an impulse response technique for a large number of sound locations surrounding the animal. Individual frequencies were extracted from the detailed spectral transformation functions (STFs) obtained for each stimulus location and, using sophisticated spatial interpolation routines, were used to calculate the directional response of the periphery at that frequency. The strength of the directional response was directly related to the analysis frequency. Furthermore, as the analysis frequency was increased to 20 kHz, the orientation of the directional response increased in elevation from the horizon (E0 degrees) to about E30 degrees, while the azimuthal location remained fairly constant at 30 degrees to 40 degrees from the midline. For analysis frequencies above 20 kHz, the response became increasingly directional toward the ipsilateral interaural axis. The interaural level differences (ILDs) were also calculated for all animals studied. ILDs increased from around 5 to 25 dB over the range of frequencies from 3-24 kHz. The two-dimensional patterns of iso-ILD contours were roughly concentric and centered on the interaural axis for frequencies below 16 kHz. For higher frequencies, there was a tendency for the ILD contours to be centered on more anterior and inferior locations. The increased directionality of the auditory periphery with increasing analysis frequency, together with the presence of sharp nulls in the response at high analysis frequencies, is consistent with a diffractive effect produced by the aperture of the pinna. However, this simple model does not predict the directional responses over the low to middle frequency range. | |||||
BibTeX:
@article{Carlile1990,
author = {S. Carlile},
title = {The auditory periphery of the ferret. I: Directional response properties and the pattern of interaural level differences.},
journal = {J Acoust Soc Am},
year = {1990},
volume = {88},
number = {5},
pages = {2180--2195}
}
|
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| Carlile, S. & Best, V. | Discrimination of sound source velocity in human listeners. | 2002 | J Acoust Soc Am | article | |
| Abstract: The ability of six human subjects to discriminate the velocity of moving sound sources was examined using broadband stimuli presented in virtual auditory space. Subjects were presented with two successive stimuli moving in the frontal horizontal plane level with the ears, and were required to judge which moved the fastest. Discrimination thresholds were calculated for reference velocities of 15, 30, and 60 degrees/s under three stimulus conditions. In one condition, stimuli were centered on 0 degrees azimuth and their duration varied randomly to prevent subjects from using displacement as an indicator of velocity. Performance varied between subjects giving median thresholds of 5.5, 9.1, and 14.8 degrees/s for the three reference velocities, respectively. In a second condition, pairs of stimuli were presented for a constant duration and subjects would have been able to use displacement to assist their judgment as faster stimuli traveled further. It was found that thresholds decreased significantly for all velocities (3.8, 7.1, and 9.8 degrees/s), suggesting that the subjects were using the additional displacement cue. The third condition differed from the second in that the stimuli were "anchored" on the same starting location rather than centered on the midline, thus doubling the spatial offset between stimulus endpoints. Subjects showed the lowest thresholds in this condition (2.9, 4.0, and 7.0 degrees/s). The results suggested that the auditory system is sensitive to velocity per se, but velocity comparisons are greatly aided if displacement cues are present. | |||||
BibTeX:
@article{Carlile2002,
author = {Simon Carlile and Virginia Best},
title = {Discrimination of sound source velocity in human listeners.},
journal = {J Acoust Soc Am},
year = {2002},
volume = {111},
number = {2},
pages = {1026-35}
}
|
|||||
| Carlile, S. & King, A. J. | Monaural and binaural spectrum level cues in the ferret: acoustics and the neural representation of auditory space. | 1994 | J Neurophysiol | article | |
| Abstract: 1. The role of the structures of the outer ear in producing monaural and binaural spectral cues to sound location was examined acoustically in the ferret. A probe microphone was introduced across the wall of the external auditory canal and its responses to digitally constructed wideband signals were recorded for a large number of free field locations. 2. In the intact animal the patterns of both monaural and binaural cues were asymmetrical for horizontal locations about the interaural axis. For anterior sound locations the monaural transformations demonstrated relative gains at middle and high frequencies and a location-dependent frequency notch. Changing elevation resulted in variations in the corner frequencies of these spectral features. Additionally, there was greater front-back asymmetry in the binaural spectral cues for locations in lateral space when compared with locations near the midline. 3. Surgical removal of the pinna and concha (pinnectomy) eliminated all the major front-back asymmetrical features in the horizon monaural and binaural spectral transformations as well as the elevation-dependent variations in the monaural spectra. Thus the residual transformations were ambiguous for sound locations in lateral space, resulting in "cones of confusion" centered on the interaural axis. 4. These cues were reflected in the topographic representation of auditory space in the deeper layers of the superior colliculus (SC). Previous studies have shown that spatial tuning at near-threshold sound levels is based on monaural pinna cues, whereas binaural inputs are utilized at higher levels that stimulate both ears. In the intact ferret we examined statistically the topography of the representation of sound azimuth for near-threshold and suprathreshold stimuli and the alignment of the auditory and visual representations in the SC. The distributions of auditory best positions within the SC for near- and suprathreshold stimulus levels were statistically indistinguishable, suggesting that both monaural and binaural cues are integrated in this neural representation of space. 5. Pinnectomy resulted in a large increase in the number of auditory units that responded best to two distinct locations in space. One lobe of the response was tuned appropriately in terms of the position of the unit within the SC, demonstrating that the residual acoustical cues are sufficient for the construction of a topographic representation of auditory space. However, the second region of space, thereby producing an ambiguous representation.(ABSTRACT TRUNCATED AT 400 WORDS) | |||||
BibTeX:
@article{Carlile1994,
author = {S. Carlile and A. J. King},
title = {Monaural and binaural spectrum level cues in the ferret: acoustics and the neural representation of auditory space.},
journal = {J Neurophysiol},
year = {1994},
volume = {71},
number = {2},
pages = {785--801}
}
|
|||||
| Carlile, S. & Pralong, D. | The location-dependent nature of perceptually salient features of the human head-related transfer functions. | 1994 | J Acoust Soc Am | article | |
| Abstract: The human head-related transfer function (HRTF) has been recorded binaurally from eight subjects using an "in-ear" recording system, for 343 stimulus locations around the head. There are a number of systematic changes in the HRTF as a function of horizontal location and elevation, on and off the median plane, that could be used as cues to sound location. To identify which components of the HRTF might provide perceptually salient cues to sound location, the HRTFs were transformed using an auditory filter model which accounts for the frequency dependence of auditory sensitivity and the frequency and level-dependent characteristics of the auditory filters. These transformations indicated a systematic variation in the frequency of the peak excitation as a function of the horizontal location of a broad band stimulus. Furthermore, there were differences in the frequency range over which elevation-dependent changes in the excitation patterns varied as a function of the vertical meridian. Interaural level differences were also estimated using the excitation patterns. The across frequency pattern of ILDs were roughly symmetrical about the interaural axis, although there were substantial differences between each ear in the magnitude of the ILDs generated for ipsilateral sounds locations. | |||||
BibTeX:
@article{Carlille1994,
author = {S Carlile and D Pralong},
title = {The location-dependent nature of perceptually salient features of the human head-related transfer functions.},
journal = {J Acoust Soc Am},
year = {1994},
volume = {95},
number = {6},
pages = {3445-59}
}
|
|||||
| Carlile, S. & Pralong, D. | The location-dependent nature of perceptually salient features of the human head-related transfer functions. | 1994 | J Acoust Soc Am | article | |
| Abstract: The human head-related transfer function (HRTF) has been recorded binaurally from eight subjects using an "in-ear" recording system, for 343 stimulus locations around the head. There are a number of systematic changes in the HRTF as a function of horizontal location and elevation, on and off the median plane, that could be used as cues to sound location. To identify which components of the HRTF might provide perceptually salient cues to sound location, the HRTFs were transformed using an auditory filter model which accounts for the frequency dependence of auditory sensitivity and the frequency and level-dependent characteristics of the auditory filters. These transformations indicated a systematic variation in the frequency of the peak excitation as a function of the horizontal location of a broad band stimulus. Furthermore, there were differences in the frequency range over which elevation-dependent changes in the excitation patterns varied as a function of the vertical meridian. Interaural level differences were also estimated using the excitation patterns. The across frequency pattern of ILDs were roughly symmetrical about the interaural axis, although there were substantial differences between each ear in the magnitude of the ILDs generated for ipsilateral sounds locations. | |||||
BibTeX:
@article{Carlille1994a,
author = {S. Carlile and D. Pralong},
title = {{T}he location-dependent nature of perceptually salient features of the human head-related transfer functions.},
journal = {J Acoust Soc Am},
year = {1994},
volume = {95},
number = {6},
pages = {3445--3459}
}
|
|||||
| Casseday, J. H. & Neff, W. D. | Auditory localization: role of auditory pathways in brain stem of the cat. | 1975 | J Neurophysiol | article | |
| Abstract: Cats were trained to localize sound in space. The animals' localization accuracy was determined before and after one of the following operations: 1) transection of the trapezoid body, 2) unilateral and 3) bilateral transection of the lateral lemniscus, 4) unilateral and 5) bilateral transection of the brachium of the inferior colliculus. The results after bilateral transections of the lateral lemniscus and the one deep bilateral transection of the brachium of the inferior colliculus indicate that some portion of the ascending auditory system must be intact above the medulla for an animal to be able to localize sound. A small loss in accuracy of localization was found after unilateral transection of the lateral lemniscus or brachium of the inferior colliculus. This loss, when compared with the much larger loss that monaural animals show, is an indication that binaural analysis, important for sound localization, occurs at the level of the medulla. Some transections of the trapezoid body resulted in a deficit in localization ability that appeared to be complete and permanent. The position of the lesions in the trapezoid body indicated that important encoding of the binaural cues to localization most likely occurs at the superior olivary complex, probably at the medial superior olive. But the trapezoid body or other commissures of the brain stem auditory system are probably also involved in transmission of information necessary for localization to higher centers. | |||||
BibTeX:
@article{Casseday1975,
author = {J. H. Casseday and W. D. Neff},
title = {Auditory localization: role of auditory pathways in brain stem of the cat.},
journal = {J Neurophysiol},
year = {1975},
volume = {38},
number = {4},
pages = {842--858}
}
|
|||||
| Casseday, J. H. & Neff, W. D. | Localization of pure tones. [BibTeX] |
1973 | J Acoust Soc Am | article | |
BibTeX:
@article{Casseday1973,
author = {J. H. Casseday and W. D. Neff},
title = {Localization of pure tones.},
journal = {J Acoust Soc Am},
year = {1973},
volume = {54},
number = {2},
pages = {365--372}
}
|
|||||
| Chang, E. F., Bao, S., Imaizumi, K., Schreiner, C. E. & Merzenich, M. M. | Development of spectral and temporal response selectivity in the auditory cortex. | 2005 | Proc Natl Acad Sci U S A | article | DOIURL |
| Abstract: The mechanisms by which hearing selectivity is elaborated and refined in early development are very incompletely determined. In this study, we documented contributions of progressively maturing inhibitory influences on the refinement of spectral and temporal response properties in the primary auditory cortex. Inhibitory receptive fields (IRFs) of infant rat auditory cortical neurons were spectrally far broader and had extended over far longer duration than did those of adults. The selective refinement of IRFs was delayed relative to that of excitatory receptive fields by an approximately 2-week period that corresponded to the critical period for plasticity. Local application of a GABA(A) receptor antagonist revealed that intracortical inhibition contributes to this progressive receptive field maturation for response selectivity in frequency. Conversely, it had no effect on the duration of IRFs or successive-signal cortical response recovery times. The importance of exposure to patterned acoustic inputs was suggested when both spectral and temporal IRF maturation were disrupted in rat pups reared in continuous, moderate-intensity noise. They were subsequently renormalized when animals were returned to standard housing conditions as adults. | |||||
BibTeX:
@article{Chang2005,
author = {Edward F Chang and Shaowen Bao and Kazuo Imaizumi and Christoph E Schreiner and Michael M Merzenich},
title = {{D}evelopment of spectral and temporal response selectivity in the auditory cortex.},
journal = {Proc Natl Acad Sci U S A},
year = {2005},
volume = {102},
number = {45},
pages = {16460--16465},
url = {http://dx.doi.org/10.1073/pnas.0508239102},
doi = {http://dx.doi.org/10.1073/pnas.0508239102}
}
|
|||||
| Chang, E. F. & Merzenich, M. M. | Environmental noise retards auditory cortical development. | 2003 | Science | article | DOIURL |
| Abstract: The mammalian auditory cortex normally undergoes rapid and progressive functional maturation. Here we show that rearing infant rat pups in continuous, moderate-level noise delayed the emergence of adultlike topographic representational order and the refinement of response selectivity in the primary auditory cortex (A1) long beyond normal developmental benchmarks. When those noise-reared adult rats were subsequently exposed to a pulsed pure-tone stimulus, A1 rapidly reorganized, demonstrating that exposure-driven plasticity characteristic of the critical period was still ongoing. These results demonstrate that A1 organization is shaped by a young animal's exposure to salient, structured acoustic inputs-and implicate noise as a risk factor for abnormal child development. MY NOTE: This paper is interesting because it argues for the role of the salience of the acoustic experience in the cortical development. Topographic organization in the cortex were delayed when rat pups were exposed to continuous loud noise. |
|||||
BibTeX:
@article{Chang2003_Env_Noise,
author = {Edward F. Chang and Michael M. Merzenich},
title = {Environmental noise retards auditory cortical development.},
journal = {Science},
year = {2003},
volume = {300},
number = {5618},
pages = {498--502},
url = {http://dx.doi.org/10.1126/science.1082163},
doi = {http://dx.doi.org/10.1126/science.1082163}
}
|
|||||
| Chase, S. M. & Young, E. D. | Limited segregation of different types of sound localization information among classes of units in the inferior colliculus. | 2005 | J Neurosci | article | DOIURL |
| Abstract: The auditory system uses three cues to decode sound location: interaural time differences (ITDs), interaural level differences (ILDs), and spectral notches (SNs). Initial processing of these cues is done in separate brainstem nuclei, with ITDs in the medial superior olive, ILDs in the lateral superior olive, and SNs in the dorsal cochlear nucleus. This work addresses the nature of the convergence of localization information in the central nucleus of the inferior colliculus (ICC). Ramachandran et al. (1999) argued that ICC neurons of types V, I, and O, respectively, receive their predominant inputs from ITD-, ILD-, and SN-sensitive brainstem nuclei, suggesting that these ICC response types should be differentially sensitive to localization cues. Here, single-unit responses to simultaneous manipulation of pairs of localization cues were recorded, and the mutual information between discharge rate and individual cues was quantified. Although rate responses to cue variation were generally consistent with those expected from the hypothesized anatomical connections, the differences in information were not as large as expected. Type I units provide the most information, especially about SNs in the physiologically useful range. Type I and O units provide information about ILDs, even at low frequencies at which actual ILDs are very small. ITD information is provided by a subset of all low-frequency neurons. Type V neurons provide information mainly about ITDs and the average binaural intensity. These results are the first to quantify the relative representation of cues in terms of information and suggest a variety of degrees of cue integration in the ICC. | |||||
BibTeX:
@article{Chase2005,
author = {Steven M Chase and Eric D Young},
title = {Limited segregation of different types of sound localization information among classes of units in the inferior colliculus.},
journal = {J Neurosci},
year = {2005},
volume = {25},
number = {33},
pages = {7575--7585},
url = {http://dx.doi.org/10.1523/JNEUROSCI.0915-05.2005},
doi = {http://dx.doi.org/10.1523/JNEUROSCI.0915-05.2005}
}
|
|||||
| Chen, J., Veen, B. D. V. & Hecox, K. E. | A spatial feature extraction and regularization model for the head-related transfer function. | 1995 | J Acoust Soc Am | article | |
| Abstract: A functional representation is proposed for complex valued (amplitude and phase) head-related transfer functions (HRTFs), including both frequency and spatial dependence. The frequency variation is spanned by a set of eigentransfer functions (EFs) that are generated using the Karhunen-Loève expansion. Any HRTF is represented as a weighted combination of the EFs where the weights are functions of the HRTFs spatial location and are termed spatial characteristic functions (SCFs). Samples of the SCFs are obtained by projecting the measured HRTFs onto the EFs. A regularization framework is employed to obtain a functional representation for the SCFs by fitting each set of SCF samples with a two-dimensional spline. Acoustic validation of the model's fidelity and predictive capability is provided using 2188 measured HRTFs from a KEMAR manikin and 1816 measured HRTFs from an anesthetized live cat. Errors between measured and modeled HRTFs are generally less than one percent. Larger errors occur in the contralateral regions for KEMAR and lower back regions for the cat as a consequence of the relatively small HRTF amplitudes resulting from head shadowing. Methods for reducing these errors are discussed. | |||||
BibTeX:
@article{Chen1995a,
author = {J. Chen and B. D. Van Veen and K. E. Hecox},
title = {{A} spatial feature extraction and regularization model for the head-related transfer function.},
journal = {J Acoust Soc Am},
year = {1995},
volume = {97},
number = {1},
pages = {439--452}
}
|
|||||
| Chen, Q. C., Cain, D. & Jen, P. H. | Sound pressure transformation at the pinna of Mus domesticus. | 1995 | J Exp Biol | article | |
| Abstract: Sound pressure transformation properties at the pinna of laboratory mice Mus domesticus were studied by measuring the sound pressure level of a continuous tone at a series of frequencies at the tympanic membrane as a function of the position of a sound source under free-field stimulation conditions. The spectral transformation, the interaural spectral difference, the isopressure contours and the interaural pressure difference contours were plotted. Sound pressure transformation functions showed some prominent spectral notches throughout the frequency range tested (10-80 kHz). However, the notch frequency did not appear to be systematically related to sound direction. The study of interaural pressure difference demonstrated that, when delivered from some angles within the ipsilateral frontal hemisphere, the sound pressure at the tympanic membrane of certain frequencies may be lower than that determined at the corresponding contralateral angles. For each sound frequency tested, there was an angle (the acoustic axis) within the ipsilateral frontal hemisphere from which the delivered sound reached a maximal pressure level at the tympanic membrane. However, the acoustic axis often changed to a new angle after removal of the ipsilateral pinna. In addition, sound delivered from the acoustic axis did not always generate a maximal pressure transformation. The isopressure contours determined within 2-5 dB of the maximal pressure were circumscribed, and their contained angular areas were found to decrease with increasing sound frequency. The 2 dB maximal pressure area may appear at more than one angular area for some test frequencies. Removal of the ipsilateral pinna or modification of pinna posture expanded isopressure contours irregularly and split the 2 dB maximal pressure area into several parts. The sound pressure difference determined between the angles of maximal and minimal sound pressure (the maximal directionality) increased with sound frequency regardless of pinna posture. Acoustic gain of the pinna at the acoustic axis reached 6-12 dB, depending upon sound frequency. However, the pinna gain was not always maximal at the acoustic axis for a given frequency. | |||||
BibTeX:
@article{Chen1995,
author = {Q. C. Chen and D. Cain and P. H. Jen},
title = {{S}ound pressure transformation at the pinna of {M}us domesticus.},
journal = {J Exp Biol},
year = {1995},
volume = {198},
number = {Pt 9},
pages = {2007--2023}
}
|
|||||
| Clarkson, M., Clifton, R. & Morrongiello, B. | The effects of sound duration on newborns' head orientation. | 1985 | J Exp Child Psychol | article | |
| Abstract: Two experiments assessed the importance of sound duration for eliciting head orientation responses from newborn infants. In Experiment 1, thirty infants turned with equal frequency toward 20-s continuous rattle sounds and 20-s trains of rattle segments. The duration of the rattle segments--14 and 100 ms (2/s), or 500 ms (1/s)--did not influence the likelihood of turning. Response latencies and durations proved quite similar for all stimuli. In Experiment 2, twenty-four infants heard continuous rattle sounds of four different durations: 1, 5, 10, and 20 s. They turned reliably to all stimulus durations; furthermore, the magnitude and temporal characteristics of head orientation responses did not differ for the four stimulus durations. These results s | |||||