[After-discharges of cat auditory cortex neurons].

Afterdischarges in neurons of the auditory cortex (AI) were investigated in immobilized cats. The unit activity of 40% of neurons showed afterdischarges lasting 3--5 sec. after the cessation of the pure--tone or two--tone sound stimuli. Two--tone sound complexes consisted of the 1 st and higher harmonics with different phase relations between the components. The afterdischarges depended on some parameters of the sound stimuli. When tonal signal was used, 80% of neurons with obvious afterdischarges responded to the sound frequency. As regards the sensitivity to phase shifts in two--tone stimuli, changes of the activity occurred in 70% of cortical neurons with on-, off- and on--off reactions and were related to these components of the reaction. The pattern of afterdischarges in 19 of 32 neurons in the auditory cortex was also related to the phase shifts.