A influência aguda da prática mental sobre as oscila？？es corticais delta: um estudo piloto

mental practice (mp) is a training method by which internal representation of a motor action is repeated several times to increase the individual's functional performance. this pilot study aimed to assess the acute influence of mi-based mp in oscillatory brain activity changes related to event related potential (erp) power and magnitude square of coherence (msc) at delta, alpha and beta frequencies. six healthy volunteers (aged 20-25 years) participated in this study. one-on-one 15-minute mp training sessions were provided two days per week for three weeks. the mp sessions were performed based on motor imagery (mi) of the metacarpophalangeal flexion and extension of the dominant hand index finger. electroencephalography signals were recorded before and after the training program, during spontaneous activity, mi and movement. electrodes were positioned at c3, c4 and cz locations, in accordance with the 10-20 international system. the erp power and msc were analized at c3 derivation. after mp, the erp power (normalized with the spontaneous activity power) increased especially in delta band during the mi and execution (p = 0.03). after the mp period, msc values increased for 5 subjects during mi (f = 8.85; p = 0.001) and movement execution (f = 2.37; p = 0.048), in that band. these results suggest the need to evaluate changes in delta band after the pm in new studies.