title: Encoding of temporal information by timing, rate, and place in cat auditory cortex.
abstract: A central goal in auditory neuroscience is to understand the neural coding of species-specific communication and human speech sounds. Low-rate repetitive sounds are elemental features of communication sounds, and core auditory cortical regions have been implicated in processing these information-bearing elements. Repetitive sounds could be encoded by at least three neural response properties: 1) the event-locked spike-timing precision, 2) the mean firing rate, and 3) the interspike interval (ISI). To determine how well these response aspects capture information about the repetition rate stimulus, we measured local group responses of cortical neurons in cat anterior auditory field (AAF) to click trains and calculated their mutual information based on these different codes. ISIs of the multiunit responses carried substantially higher information about low repetition rates than either spike-timing precision or firing rate. Combining firing rate and ISI codes was synergistic and captured modestly more repetition information. Spatial distribution analyses showed distinct local clustering properties for each encoding scheme for repetition information indicative of a place code. Diversity in local processing emphasis and distribution of different repetition rate codes across AAF may give rise to concurrent feed-forward processing streams that contribute differently to higher-order sound analysis.
authors.affiliation: Coleman Memorial Laboratory, W. M. Keck Center for Integrative Neuroscience, Department of Otolaryngology-Head and Neck Surgery, University of California San Francisco, San Francisco, California, United States of America. kimaiz@lsuhsc.edu
authors.forename: Kazuo
authors.initials: K
authors.lastname: Imaizumi
authors.forename: Nicholas J
authors.initials: NJ
authors.lastname: Priebe
authors.forename: Tatyana O
authors.initials: TO
authors.lastname: Sharpee
authors.forename: Steven W
authors.initials: SW
authors.lastname: Cheung
authors.forename: Christoph E
authors.initials: CE
authors.lastname: Schreiner
mesh_terms: D000161:Acoustic Stimulation; D000818:Animals; D001303:Auditory Cortex / Q000378:metabolism* / Q000502:physiology; D002415:Cats; D005260:Female