SEP signals during different conditions.

<p>Electrodes were implanted epidurally at different recording sites above the vertex (Vx), primary somatosensory cortex (S1) and the anterior cingulate cortex (Acc). The mean positive-to-negative amplitudes per session are shown by group and recording site (left column) and by group (right column) for the (A) P1-N1, (B) P2-N2 and (C) P3-N3. Data are represented as mean µV ± SEM. See “results” for details. *p<.01 versus session 1 (baseline) amplitude.