抄録
The processing of spectral and temporal information in the core fields of the left and right auditory cortices of the guinea pig was investigated using optical imaging with a voltage-sensitive dye (RH795). Eleven guinea pigs were anesthetized with ketamine (80mg/kg) and xylazine (40mg/kg). In order to compare the functional difference between the left and the right auditory cortex, optical imaging patterns to repeated sound ( tone, click, upward and downward FM sound ) at different repetition rates (4-14 Hz) were recorded from core auditory fields (primary (AI), dorsocaudal (DC) fields) of both sides. Repetition rate transfer functions (RRTF) in field AI of the left cotex were low-pass showing a sharp drop-off in evoked activity per upward FM sound at 4-6 Hz but RRTFs of the right cortex were bandpass with the peak of 6 Hz. On the other hand, the cut-off frequencies of RRTFs per downward FM sounds in field AI of the left cortex were 6-8 Hz and those of the right cortex were 6 Hz. We discuss the functional difference between the left and right auditory cortices of guinea pigs. [J Physiol Sci. 2008;58 Suppl:S171]
