Change-related responses in the human auditory cortex: an MEG study.
We recorded cortical activity in response to the onset, offset, and frequency change of a pure tone using magnetencephalograms (MEGs) to clarify the physiological significance of N1m relating to the detection of changes. Four interstimulus intervals (ISIs) (0.5, 1.5, 3, and 6 s) were used for each of the three auditory events. Results showed that (i) all three auditory events elicited N1m with a similar topography and similar temporal profile, (ii) the source of N1m was located in the superior temporal gyrus (STG) for all events under all ISI conditions, (iii) the amplitude of the STG activity as a function of the duration of the steady state preceding the change was similar among the three events, and (iv) there was a significant positive correlation in amplitude between on-N1m and off-N1m and between on-N1m and change-N1m. These results suggested that N1m for the three events has a similar physiological significance relating to the detection of changes.
Department of Integrative Physiology, National Institute for Physiological Sciences, Okazaki, Japan. koya@nips.ac.jp
Koya
K
Yamashiro
Koji
K
Inui
Naofumi
N
Otsuru
Ryusuke
R
Kakigi
D000161:Acoustic Stimulation; D000328:Adult; D000704:Analysis of Variance; D001303:Auditory Cortex / Q000502:physiology*; D001307:Auditory Perception / Q000502:physiology*; D001931:Brain Mapping; D005072:Evoked Potentials, Auditory / Q000502:physiology*; D005260:Female; D006801:Humans; D015225:Magnetoencephalography; D008297:Male; D008875:Middle Aged; D009474:Neurons / Q000502:physiology; D012044:Regression Analysis