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Neural circuits underlying adaptation and learning in the perception of auditory space.

King AJ, Dahmen JC, Keating P, Leach ND, Nodal FR, Bajo VM - Neurosci Biobehav Rev (2011)

Bottom Line: Sound localization mechanisms are particularly plastic during development, when the monaural and binaural acoustic cues that form the basis for spatial hearing change in value as the body grows.Recent studies have shown that the mature brain retains a surprising capacity to relearn to localize sound in the presence of substantially altered auditory spatial cues.Through a combination of recording studies and methods for selectively manipulating the activity of specific neuronal populations, progress is now being made in identifying the cortical and subcortical circuits in the brain that are responsible for the dynamic coding of auditory spatial information.

View Article: PubMed Central - PubMed

Affiliation: Department of Physiology, Anatomy and Genetics, Sherrington Building, University of Oxford, Parks Road, Oxford, UK. andrew.king@dpag.ox.ac.uk

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Effects of chronic monaural occlusion in infancy on the accuracy and precision of auditory localization. (A) Schematic view of the chamber used to measure the sound localization ability of ferrets. Animals were trained to stand on a start platform and initiate a trial by licking the center spout. Each trial consisted of a Gaussian noise burst (0–22 kHz, 200 ms duration) presented quasirandomly from one of 12 speakers placed at 30° intervals in the azimuthal plane. Amplitude spectra were divided up into 1/6th octave bands and the level of each band was varied independently, with all variations in level chosen randomly on each trial from a normal distribution with a standard deviation of 5 dB. Within each testing session, five sound levels ranging randomly from 56 to 84 dB SPL were used to minimize loudness cues. Ferrets were rewarded for approaching and licking the spout associated with the speaker that had been triggered. (B–E) Stimulus–response plots showing sound localization performance in ferrets. Each plot illustrates the distribution of responses as a function of stimulus location, with the size of each dot determined by the proportion of responses made to different spout locations. Data are plotted for normally reared ferrets in the absence of an earplug (B), ferrets reared with an earplug immediately after the earplug was removed (C), normally reared ferrets following the insertion of an earplug for the first time (D), and ferrets reared with an earplug with the earplug still in place (E). Note that the animals reared with one ear occluded could localize sound almost as well as the normally reared controls.
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fig0010: Effects of chronic monaural occlusion in infancy on the accuracy and precision of auditory localization. (A) Schematic view of the chamber used to measure the sound localization ability of ferrets. Animals were trained to stand on a start platform and initiate a trial by licking the center spout. Each trial consisted of a Gaussian noise burst (0–22 kHz, 200 ms duration) presented quasirandomly from one of 12 speakers placed at 30° intervals in the azimuthal plane. Amplitude spectra were divided up into 1/6th octave bands and the level of each band was varied independently, with all variations in level chosen randomly on each trial from a normal distribution with a standard deviation of 5 dB. Within each testing session, five sound levels ranging randomly from 56 to 84 dB SPL were used to minimize loudness cues. Ferrets were rewarded for approaching and licking the spout associated with the speaker that had been triggered. (B–E) Stimulus–response plots showing sound localization performance in ferrets. Each plot illustrates the distribution of responses as a function of stimulus location, with the size of each dot determined by the proportion of responses made to different spout locations. Data are plotted for normally reared ferrets in the absence of an earplug (B), ferrets reared with an earplug immediately after the earplug was removed (C), normally reared ferrets following the insertion of an earplug for the first time (D), and ferrets reared with an earplug with the earplug still in place (E). Note that the animals reared with one ear occluded could localize sound almost as well as the normally reared controls.

Mentions: Although the mechanisms underlying the particularly accurate sound localization abilities of the barn owl show a number of specializations that have not been observed in other species, studies in mammals have confirmed the adaptive nature of sound localization during development. In particular, adult ferrets tend to exhibit largely normal sound localization behavior after being raised with a unilateral earplug (King et al., 2000; Fig. 2). The after-effects associated with earplug removal, however, are much less pronounced than those reported in barn owls, suggesting that the mechanisms underlying adaptation may differ across species.


Neural circuits underlying adaptation and learning in the perception of auditory space.

King AJ, Dahmen JC, Keating P, Leach ND, Nodal FR, Bajo VM - Neurosci Biobehav Rev (2011)

Effects of chronic monaural occlusion in infancy on the accuracy and precision of auditory localization. (A) Schematic view of the chamber used to measure the sound localization ability of ferrets. Animals were trained to stand on a start platform and initiate a trial by licking the center spout. Each trial consisted of a Gaussian noise burst (0–22 kHz, 200 ms duration) presented quasirandomly from one of 12 speakers placed at 30° intervals in the azimuthal plane. Amplitude spectra were divided up into 1/6th octave bands and the level of each band was varied independently, with all variations in level chosen randomly on each trial from a normal distribution with a standard deviation of 5 dB. Within each testing session, five sound levels ranging randomly from 56 to 84 dB SPL were used to minimize loudness cues. Ferrets were rewarded for approaching and licking the spout associated with the speaker that had been triggered. (B–E) Stimulus–response plots showing sound localization performance in ferrets. Each plot illustrates the distribution of responses as a function of stimulus location, with the size of each dot determined by the proportion of responses made to different spout locations. Data are plotted for normally reared ferrets in the absence of an earplug (B), ferrets reared with an earplug immediately after the earplug was removed (C), normally reared ferrets following the insertion of an earplug for the first time (D), and ferrets reared with an earplug with the earplug still in place (E). Note that the animals reared with one ear occluded could localize sound almost as well as the normally reared controls.
© Copyright Policy
Related In: Results  -  Collection

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Show All Figures
getmorefigures.php?uid=PMC3198863&req=5

fig0010: Effects of chronic monaural occlusion in infancy on the accuracy and precision of auditory localization. (A) Schematic view of the chamber used to measure the sound localization ability of ferrets. Animals were trained to stand on a start platform and initiate a trial by licking the center spout. Each trial consisted of a Gaussian noise burst (0–22 kHz, 200 ms duration) presented quasirandomly from one of 12 speakers placed at 30° intervals in the azimuthal plane. Amplitude spectra were divided up into 1/6th octave bands and the level of each band was varied independently, with all variations in level chosen randomly on each trial from a normal distribution with a standard deviation of 5 dB. Within each testing session, five sound levels ranging randomly from 56 to 84 dB SPL were used to minimize loudness cues. Ferrets were rewarded for approaching and licking the spout associated with the speaker that had been triggered. (B–E) Stimulus–response plots showing sound localization performance in ferrets. Each plot illustrates the distribution of responses as a function of stimulus location, with the size of each dot determined by the proportion of responses made to different spout locations. Data are plotted for normally reared ferrets in the absence of an earplug (B), ferrets reared with an earplug immediately after the earplug was removed (C), normally reared ferrets following the insertion of an earplug for the first time (D), and ferrets reared with an earplug with the earplug still in place (E). Note that the animals reared with one ear occluded could localize sound almost as well as the normally reared controls.
Mentions: Although the mechanisms underlying the particularly accurate sound localization abilities of the barn owl show a number of specializations that have not been observed in other species, studies in mammals have confirmed the adaptive nature of sound localization during development. In particular, adult ferrets tend to exhibit largely normal sound localization behavior after being raised with a unilateral earplug (King et al., 2000; Fig. 2). The after-effects associated with earplug removal, however, are much less pronounced than those reported in barn owls, suggesting that the mechanisms underlying adaptation may differ across species.

Bottom Line: Sound localization mechanisms are particularly plastic during development, when the monaural and binaural acoustic cues that form the basis for spatial hearing change in value as the body grows.Recent studies have shown that the mature brain retains a surprising capacity to relearn to localize sound in the presence of substantially altered auditory spatial cues.Through a combination of recording studies and methods for selectively manipulating the activity of specific neuronal populations, progress is now being made in identifying the cortical and subcortical circuits in the brain that are responsible for the dynamic coding of auditory spatial information.

View Article: PubMed Central - PubMed

Affiliation: Department of Physiology, Anatomy and Genetics, Sherrington Building, University of Oxford, Parks Road, Oxford, UK. andrew.king@dpag.ox.ac.uk

Show MeSH
Related in: MedlinePlus