Pm. Rossini et al., SOMATOSENSORY-EVOKED POTENTIALS DURING THE IDEATION AND EXECUTION OF INDIVIDUAL FINGER MOVEMENTS, Muscle & nerve, 19(2), 1996, pp. 191-202
Scalp somatosensory evoked potentials (SEPs) were recorded in 10 volun
teers after median nerve stimulation, in four experimental conditions
of hand movements performance/ideation, and compared with the baseline
condition of full relaxation. The experimental conditions were (a) se
lf-improvised hand-finger sequential movements; (b) the same movements
according to a read sequence of numbers; (c) mental ideation of finge
r movements; and (d) passive displacement of fingers in complete relax
ation. Latencies and amplitudes of the parietal (N20, P25, N33, and P4
5) and frontal peaks (P20-22, N30, and P40) were analyzed. latencies d
id not vary in any of the paradigms. Among the parietal complexes, onl
y the P25-N33 amplitude was significantly reduced in (a), (b), (c), an
d (d) and the N20-P25 was reduced in (a) and (d); among frontal waves,
N30 and P40 were significantly reduced (20-75%) in (a) and (b). Coron
al electrodes showed amplitude decrements maximal at the frontal-rolan
dic positions contralateral to the stimulated side. (C) 1996 John Wile
y & Sons, Inc.