Fig 3. Frequency response areas (FRA) of early and late activations and quantification of FMR-shift.

A.-C. Mean peak amplitudes of early (S1) and late (S2) current sink activity as a function of stimulation frequency and intensity referenced to the CF (black asterisk). A. FRA of early current sink activity in thalamocortical input layers showed increase of response bandwidth (BW) and decrease of FMR with increasing intensity. B. Cortical silencing reduced response bandwidth and shifts of the FMR, but did not affect response threshold. C. FRA of later activity in supragranular layers (S2) before cortical silencing showed increasing response bandwidth without systematic FMR-shift in dependence of the stimulus intensity.