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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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Lesions of auditory cortex impair sound localization and training-induced plasticity. Left column shows the extent of the auditory cortical lesions in different animals. The top panel shows the main subdivisions superimposed over the auditory cortex on a ferret brain. The middle panel shows an extended lesion that comprised the whole cortical thickness, including the white matter and most of the auditory cortex. The bottom panel shows a restricted lesion affecting only the primary auditory cortex (A1) while preserving the underlying white matter. The plots in the middle column show the percentage of correct responses in a 12-speaker approach-to-target task (see Fig. 2A) at 3 different sound durations (1000, 200 and 40 ms). When short duration sounds were used, control ferrets exhibited reduced spatial accuracy at lateral and posterior positions compared with anterior positions (top panel). A1 lesions degraded the accuracy with which brief sounds were localized, without affecting performance at longer durations (bottom panel), whereas larger deficits, affecting performance at all sound durations tested, were observed following extensive lesions of the auditory cortex (middle panel). The right column shows the ability of the animals to adapt to the altered spatial cues produced by plugging one ear. The top panel shows data from a control ferret: after an initial fall in the percentage of correct scores following earplug insertion, the animal's performance gradually recovered with training to almost reach pre-plug levels. This training-induced plasticity depends on the integrity of the auditory cortex as no improvement in performance was observed in animals with cortical lesions, even if the region aspirated was restricted to A1 (middle and bottom panels). Abbreviations: as, ansinate sulcus; A1, primary auditory cortex; AAF, anterior auditory field; AEG, anterior ectosylvian gyrus; ls, lateral sulcus; LV, lateral ventricle; MEG, middle ectosylvian gyrus; PEG, posterior ectosylvian gyrus; pss, pseudosylvian sulcus; SSG, suprasylvian gyrus; sss, suprasylvian sulcus.
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fig0015: Lesions of auditory cortex impair sound localization and training-induced plasticity. Left column shows the extent of the auditory cortical lesions in different animals. The top panel shows the main subdivisions superimposed over the auditory cortex on a ferret brain. The middle panel shows an extended lesion that comprised the whole cortical thickness, including the white matter and most of the auditory cortex. The bottom panel shows a restricted lesion affecting only the primary auditory cortex (A1) while preserving the underlying white matter. The plots in the middle column show the percentage of correct responses in a 12-speaker approach-to-target task (see Fig. 2A) at 3 different sound durations (1000, 200 and 40 ms). When short duration sounds were used, control ferrets exhibited reduced spatial accuracy at lateral and posterior positions compared with anterior positions (top panel). A1 lesions degraded the accuracy with which brief sounds were localized, without affecting performance at longer durations (bottom panel), whereas larger deficits, affecting performance at all sound durations tested, were observed following extensive lesions of the auditory cortex (middle panel). The right column shows the ability of the animals to adapt to the altered spatial cues produced by plugging one ear. The top panel shows data from a control ferret: after an initial fall in the percentage of correct scores following earplug insertion, the animal's performance gradually recovered with training to almost reach pre-plug levels. This training-induced plasticity depends on the integrity of the auditory cortex as no improvement in performance was observed in animals with cortical lesions, even if the region aspirated was restricted to A1 (middle and bottom panels). Abbreviations: as, ansinate sulcus; A1, primary auditory cortex; AAF, anterior auditory field; AEG, anterior ectosylvian gyrus; ls, lateral sulcus; LV, lateral ventricle; MEG, middle ectosylvian gyrus; PEG, posterior ectosylvian gyrus; pss, pseudosylvian sulcus; SSG, suprasylvian gyrus; sss, suprasylvian sulcus.

Mentions: Although a reduced ability to localize sound results when A1 alone is silenced, larger deficits are observed when surrounding auditory cortical areas are affected as well (Fig. 3), suggesting that different parts of the auditory cortex are required for the processing of spatial information. Indeed, there is both physiological (Harrington et al., 2008; Miller and Recanzone, 2009; Bizley and King, 2011) and behavioral (Malhotra et al., 2008) evidence that certain non-primary areas make larger contributions to sound localization. Exactly how the cortex underpins the perception of auditory space remains uncertain, but the failure to find a topographic representation equivalent to that present in the SC (Palmer and King, 1982) has prompted the idea that sound-source location is encoded by the spatial distribution of activity across populations of cortical neurons (Miller and Recanzone, 2009; Stecker et al., 2005).


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)

Lesions of auditory cortex impair sound localization and training-induced plasticity. Left column shows the extent of the auditory cortical lesions in different animals. The top panel shows the main subdivisions superimposed over the auditory cortex on a ferret brain. The middle panel shows an extended lesion that comprised the whole cortical thickness, including the white matter and most of the auditory cortex. The bottom panel shows a restricted lesion affecting only the primary auditory cortex (A1) while preserving the underlying white matter. The plots in the middle column show the percentage of correct responses in a 12-speaker approach-to-target task (see Fig. 2A) at 3 different sound durations (1000, 200 and 40 ms). When short duration sounds were used, control ferrets exhibited reduced spatial accuracy at lateral and posterior positions compared with anterior positions (top panel). A1 lesions degraded the accuracy with which brief sounds were localized, without affecting performance at longer durations (bottom panel), whereas larger deficits, affecting performance at all sound durations tested, were observed following extensive lesions of the auditory cortex (middle panel). The right column shows the ability of the animals to adapt to the altered spatial cues produced by plugging one ear. The top panel shows data from a control ferret: after an initial fall in the percentage of correct scores following earplug insertion, the animal's performance gradually recovered with training to almost reach pre-plug levels. This training-induced plasticity depends on the integrity of the auditory cortex as no improvement in performance was observed in animals with cortical lesions, even if the region aspirated was restricted to A1 (middle and bottom panels). Abbreviations: as, ansinate sulcus; A1, primary auditory cortex; AAF, anterior auditory field; AEG, anterior ectosylvian gyrus; ls, lateral sulcus; LV, lateral ventricle; MEG, middle ectosylvian gyrus; PEG, posterior ectosylvian gyrus; pss, pseudosylvian sulcus; SSG, suprasylvian gyrus; sss, suprasylvian sulcus.
© Copyright Policy
Related In: Results  -  Collection

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getmorefigures.php?uid=PMC3198863&req=5

fig0015: Lesions of auditory cortex impair sound localization and training-induced plasticity. Left column shows the extent of the auditory cortical lesions in different animals. The top panel shows the main subdivisions superimposed over the auditory cortex on a ferret brain. The middle panel shows an extended lesion that comprised the whole cortical thickness, including the white matter and most of the auditory cortex. The bottom panel shows a restricted lesion affecting only the primary auditory cortex (A1) while preserving the underlying white matter. The plots in the middle column show the percentage of correct responses in a 12-speaker approach-to-target task (see Fig. 2A) at 3 different sound durations (1000, 200 and 40 ms). When short duration sounds were used, control ferrets exhibited reduced spatial accuracy at lateral and posterior positions compared with anterior positions (top panel). A1 lesions degraded the accuracy with which brief sounds were localized, without affecting performance at longer durations (bottom panel), whereas larger deficits, affecting performance at all sound durations tested, were observed following extensive lesions of the auditory cortex (middle panel). The right column shows the ability of the animals to adapt to the altered spatial cues produced by plugging one ear. The top panel shows data from a control ferret: after an initial fall in the percentage of correct scores following earplug insertion, the animal's performance gradually recovered with training to almost reach pre-plug levels. This training-induced plasticity depends on the integrity of the auditory cortex as no improvement in performance was observed in animals with cortical lesions, even if the region aspirated was restricted to A1 (middle and bottom panels). Abbreviations: as, ansinate sulcus; A1, primary auditory cortex; AAF, anterior auditory field; AEG, anterior ectosylvian gyrus; ls, lateral sulcus; LV, lateral ventricle; MEG, middle ectosylvian gyrus; PEG, posterior ectosylvian gyrus; pss, pseudosylvian sulcus; SSG, suprasylvian gyrus; sss, suprasylvian sulcus.
Mentions: Although a reduced ability to localize sound results when A1 alone is silenced, larger deficits are observed when surrounding auditory cortical areas are affected as well (Fig. 3), suggesting that different parts of the auditory cortex are required for the processing of spatial information. Indeed, there is both physiological (Harrington et al., 2008; Miller and Recanzone, 2009; Bizley and King, 2011) and behavioral (Malhotra et al., 2008) evidence that certain non-primary areas make larger contributions to sound localization. Exactly how the cortex underpins the perception of auditory space remains uncertain, but the failure to find a topographic representation equivalent to that present in the SC (Palmer and King, 1982) has prompted the idea that sound-source location is encoded by the spatial distribution of activity across populations of cortical neurons (Miller and Recanzone, 2009; Stecker et al., 2005).

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