Resonance-like frequencies of sensorimotor areas evoked by repetitive tactile stimulation

The aim of the present study was to investigate resonance-like frequencies of somatosensory steady-state evoked potentials (SSSEPs) during mechanical stimulation of the left and right index finger. The resonance effects were studied in a group of normal subjects at 8 frequencies between 17 Hz and 31 Hz. Band power was computed in 2 s epochs in eight 2 Hz beta bands starting from 16-18 Hz up to 30-32 Hz and referred to a baseline prior to stimulation, For each subject the band with the largest band power increase was determined on electrodes overlying the contralateral hand area. The band power maxima and therewith the ,,resonance-like frequencies were found around 27 Hz.