Responses of the human auditory cortex to changes in one versus two stimulus features
✍ Scribed by Sari Levänen; Riitta Hari; Linda McEvoy; Mikko Sams
- Publisher
- Springer-Verlag
- Year
- 1993
- Tongue
- English
- Weight
- 616 KB
- Volume
- 97
- Category
- Article
- ISSN
- 0014-4819
No coin nor oath required. For personal study only.
✦ Synopsis
Neuromagnetic responses were recorded with a 24-SQUID magnetometer in two "oddball" experiments to determine whether mismatch responses to changes in single stimulus features are additive. In experiment 1, the one-feature deviants differed from standards in interstimulus interval (ISI) or frequency, and the two-feature deviants in both ISI and frequency. In experiment 2, deviants differed in duration, frequency, or both. All deviants evoked a mismatch field (MMF) with sources close to each other in the supratemporal auditory cortex. Except for the ISI deviants, the MMF sources were about 1 cm anterior to the source of the 100-ms response, N100m, to the standards. In the two experiments, MMFs obtained in response to the two-feature deviants resembled closely the sum of MMFs in response to one-feature deviants. The results suggest that the standards leave a multiple neuronal representation in the human auditory cortex. The particular neuronal traces of the representation react independently to changes in different features of sound stimuli.