Biomaterial Database

Spectral-ripple representation of steady-state vowels in primary auditory cortex. 1998

H Versnel, and S A Shamma

Institute for Systems Research and Electrical Engineering Department, University of Maryland, College Park 20742, USA. hv@physiol.ox.ac.uk

Responses to various steady-state vowels were recorded in single units in the primary auditory cortex (AI) of the barbiturate-anaesthetized ferret. Six vowels were presented (/a/, /epsilon/, 2 different /i/'s, and 2 different /u/'s) in a natural voiced and a synthetic unvoiced mode. In addition, the responses to broadband stimuli with a sinusoidally shaped spectral envelope (called ripple stimuli) were recorded in each cell, and the response field (RF), which consists of both excitatory and inhibitory regions, was derived from the ripple transfer function. We examined whether the vowel responses could be predicted using a linear ripple analysis method [Shamma et al., Auditory Neurosci. 1, 233-254 (1995)], i.e., by cross correlating the RF of the single unit, and the smoothed spectral envelope of the vowel. We found that for most AI cells (71%) the relative responses to natural vowels could be predicted on the basis of this method. Responses and prediction results for unvoiced and voiced vowels were very similar, suggesting that the spectral fine structure may not play a significant role in the neuron's response to the vowels. Predictions on the basis of the entire RF were significantly better than based solely on best frequency (BF) (or "place"). These findings confirm the ripple analysis method as a valid method to characterize AI responses to broadband sounds as we proposed in a previous paper using synthesized spectra [Shamma and Versnel, Auditory Neurosci. 1, 255-270 (1995)].

UI	MeSH Term	Description	Entries
D008954	Models, Biological	Theoretical representations that simulate the behavior or activity of biological processes or diseases. For disease models in living animals, DISEASE MODELS, ANIMAL is available. Biological models include the use of mathematical equations, computers, and other electronic equipment.	Biological Model,Biological Models,Model, Biological,Models, Biologic,Biologic Model,Biologic Models,Model, Biologic
D010700	Phonetics	The science or study of speech sounds and their production, transmission, and reception, and their analysis, classification, and transcription. (Random House Unabridged Dictionary, 2d ed)	Speech Sounds,Sound, Speech,Sounds, Speech,Speech Sound
D005072	Evoked Potentials, Auditory	The electric response evoked in the CEREBRAL CORTEX by ACOUSTIC STIMULATION or stimulation of the AUDITORY PATHWAYS.	Auditory Evoked Potentials,Auditory Evoked Response,Auditory Evoked Potential,Auditory Evoked Responses,Evoked Potential, Auditory,Evoked Response, Auditory,Evoked Responses, Auditory,Potentials, Auditory Evoked
D005289	Ferrets	Semidomesticated variety of European polecat much used for hunting RODENTS and/or RABBITS and as a laboratory animal. It is in the subfamily Mustelinae, family MUSTELIDAE.	Domestic Polecat,Domestic Polecats,European Polecat,European Polecats,Ferret,Mustela putorius,Mustela putorius furo,Polecat, Domestic,Polecat, European,Polecats, Domestic,Polecats, European
D000818	Animals	Unicellular or multicellular, heterotrophic organisms, that have sensation and the power of voluntary movement. Under the older five kingdom paradigm, Animalia was one of the kingdoms. Under the modern three domain model, Animalia represents one of the many groups in the domain EUKARYOTA.	Animal,Metazoa,Animalia
D001303	Auditory Cortex	The region of the cerebral cortex that receives the auditory radiation from the MEDIAL GENICULATE BODY.	Brodmann Area 41,Brodmann Area 42,Brodmann's Area 41,Heschl Gyrus,Heschl's Gyrus,Auditory Area,Heschl's Convolutions,Heschl's Gyri,Primary Auditory Cortex,Temporal Auditory Area,Transverse Temporal Gyri,Area 41, Brodmann,Area 41, Brodmann's,Area 42, Brodmann,Area, Auditory,Area, Temporal Auditory,Auditory Areas,Auditory Cortex, Primary,Brodmanns Area 41,Cortex, Auditory,Cortex, Primary Auditory,Gyrus, Heschl,Gyrus, Heschl's,Gyrus, Transverse Temporal,Heschl Convolutions,Heschl Gyri,Heschls Convolutions,Heschls Gyri,Heschls Gyrus,Primary Auditory Cortices,Temporal Auditory Areas,Temporal Gyrus, Transverse,Transverse Temporal Gyrus
D013067	Speech Perception	The process whereby an utterance is decoded into a representation in terms of linguistic units (sequences of phonetic segments which combine to form lexical and grammatical morphemes).	Speech Discrimination,Discrimination, Speech,Perception, Speech