Abstract
The auditory cortex represents spatial locations differently from other sensory modalities. While visual and tactile cortices utilize topographical space maps, for audition no such cortical map has been found. Instead, auditory cortical neurons have wide spatial receptive fields and together they form a population rate code of sound source location. Recent studies have shown that this code is modulated by task conditions so that during auditory tasks it provides better selectivity to sound source location than during idle listening. The goal of this study was to establish whether the neural representation of auditory space can also be influenced by task conditions involving other sensory modalities than hearing. Therefore, we conducted magnetoencephalography (MEG) recordings in which auditory spatial selectivity of the human cortex was probed with an adaptation paradigm while subjects performed a visual task. Engaging in the task led to an increase in neural selectivity to sound source location compared to when no task was performed. This suggests that an enhancement in the population rate code of auditory space took place during task performance. This enhancement in auditory spatial selectivity was independent of the direction of visual orientation. Together with previous studies, these findings suggest that performing any demanding task, even one in which sounds and their source locations are irrelevant, can lead to enhancements in the neural representation of auditory space. Such mechanisms may have great survival value as sounds are capable of producing location information on potentially relevant events in all directions and over long distances.
Highlights
The way the auditory system represents location constitutes a major deviation from how space is represented in other sensory modalities
Here, we conducted an MEG experiment in order to determine whether orienting to visual stimuli could enhance the selectivity of auditory cortical neurons to sound source location
We measured responses to spatial sounds in a stimulus-specific adaptation paradigm while subjects were engaged in a visual task
Summary
The way the auditory system represents location constitutes a major deviation from how space is represented in other sensory modalities. The auditory cortex uses a population rate code for representing horizontal sound source location (Stecker et al, 2005; Werner-Reiss and Groh, 2008; Salminen et al, 2009, 2012; Magezi and Krumbholz, 2010; Briley et al, 2013). In this hemifield or opponent code, horizontal sound source location is represented in the activity of two widely tuned populations, one preferring sounds in the left and the other those in the right hemifield of the auditory space
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
