Dual Representation of the Auditory Space.

Area of Science:

• Neuroscience
• Auditory Perception
• Cognitive Psychology

Background:

• Auditory spatial cues serve dual functions: explicit sound source localization and location-linked sound object representation.
• Previous research indicates right-hemispheric dominance for explicit sound localization.
• A clinical case study revealed a dissociation, with impaired localization but preserved spatial cue use for sound object segregation.

Purpose of the Study:

• To review evidence on brain regions involved in the location-linked representation of sound objects.
• To investigate how auditory evoked potentials (AEP) and functional magnetic resonance imaging (fMRI) studies explore this aspect.
• To synthesize findings from lesion studies and neuroimaging to understand hemispheric involvement.

Main Methods:

• Systematic literature search for Auditory Evoked Potential (AEP) and functional magnetic resonance imaging (fMRI) studies.
• Studies compared the encoding of stationary versus moving sound objects.
• Inclusion of studies examining anatomical correlates of impaired spatial cue-based sound object segregation after brain lesions.

Main Results:

• Identified 1 AEP study and 12 fMRI studies meeting the search criteria.
• Evidence indicates that location-linked representation of sound objects predominantly involves the left hemisphere, with some right-hemisphere contribution.
• Location-linked encoding occurs in early auditory areas and the temporal voice area, where it benefits emotional valence processing.

Conclusions:

• The location-linked representation of sound objects shows a distinct hemispheric involvement compared to explicit sound localization.
• The left hemisphere plays a significant role in encoding the spatial attributes of sound objects.
• This spatial encoding mechanism in auditory areas also influences the processing of emotional valence.