title: Tonotopic mapping in auditory cortex of the chinchilla.
abstract: Using single-unit electrophysiological methods we have mapped sound frequency (or cochleotopic) representation in the auditory cortex of the chinchilla. We describe the surgical approach to expose this area. We report on maps from six subjects and note a considerable variation in shape between individuals. In general, the primary area has a cochleotopic/tonotopic organization in which low frequencies are represented rostrally and higher frequencies caudally. Neurons in the primary area have latency and tuning properties comparable to other mammalian species. A region anterior to the primary (AI) auditory are has a reverse tonotopic map and may be analogous to the anterior auditory field (AAF) reported in other species.
authors.affiliation: Department of Otolaryngology, Hospital for Sick Children, Toronto, Ont., Canada. robert.harrison@mailhub.sickkids.on.ca
authors.forename: R V
authors.initials: RV
authors.lastname: Harrison
authors.forename: A
authors.initials: A
authors.lastname: Kakigi
authors.forename: H
authors.initials: H
authors.lastname: Hirakawa
authors.forename: N
authors.initials: N
authors.lastname: Harel
authors.forename: R J
authors.initials: RJ
authors.lastname: Mount
mesh_terms: D000161:Acoustic Stimulation; D000818:Animals; D001303:Auditory Cortex / Q000378:metabolism / Q000502:physiology*; D001309:Auditory Threshold / Q000502:physiology*; D002682:Chinchilla; D003051:Cochlea / Q000378:metabolism / Q000502:physiology; D004594:Electrophysiology