title: Influence of inter-field communication on neuronal response synchrony across auditory cortex.
abstract: Sensory information is encoded by cortical neurons in the form of synaptic discharge time and rate level. These neuronal codes generate response patterns across cell assemblies that are crucial to various cognitive functions. Despite pivotal information about structural and cognitive factors involved in the generation of synchronous neuronal responses such as stimulus context, attention, age, cortical depth, sensory experience, and receptive field properties, the influence of cortico-cortical connectivity on the emergence of neuronal response patterns is poorly understood. The present investigation assesses the role of cortico-cortical connectivity in the modulation of neuronal discharge synchrony across auditory cortex cell-assemblies. Acute single-unit recording techniques in combination with reversible cooling deactivation procedures were used in the domestic cat (Felis catus). Recording electrodes were positioned across primary and non-primary auditory fields and neuronal activity was measured before, during, and after synaptic deactivation of adjacent cortical regions in the presence of acoustic stimulation. Cross-correlation functions of simultaneously recorded units were generated and changes in response synchrony levels across cooling conditions were measured. Data analyses revealed significant decreases in response time coincidences between cortical neurons during periods of cortical deactivation. Collectively, the results of the present investigation demonstrate that cortical neurons participate in the modulation of response synchrony levels across neuronal assemblies of primary and non-primary auditory fields.
authors.affiliation: Cerebral Systems Laboratory, University of Western Ontario, London, ON N6A 5C1, Canada; Department of Physiology and Pharmacology, University of Western Ontario, London, ON N6A 5C1, Canada.
authors.forename: Andres
authors.initials: A
authors.lastname: Carrasco
authors.forename: Stephen G
authors.initials: SG
authors.lastname: Lomber
mesh_terms: D000161:Acoustic Stimulation; D000818:Animals; D001303:Auditory Cortex / Q000502:physiology*; D001306:Auditory Pathways / Q000502:physiology; D002415:Cats; D055724:Electrophysiological Phenomena; D005072:Evoked Potentials, Auditory; D011984:Sensory Receptor Cells / Q000502:physiology; D009435:Synaptic Transmission
keywords: A; AAF; AI; AII; D; DZ; FAES; IN; P; PAF; T; V; VAF; VPAF; aes; anterior; anterior auditory field; anterior ectosylvian sulcus; auditory field of the anterior ectosylvian sulcus; dPE; dorsal; dorsal posterior ectosylvian area; dorsal zone of auditory cortex; iPE; insular region; intermediate posterior ectosylvian area; pes; posterior; posterior auditory field; posterior ectosylvian sulcus; primary auditory cortex; second auditory cortex; ss; suprasylvian sulcus; temporal region; vPE; ventral; ventral auditory field; ventral posterior auditory field; ventral posterior ectosylvian area