TEMPORAL AND SPATIAL ADAPTATIONS DURING THE ACQUISITION OF A REVERSALMOVEMENT

Adjustments of the biphasic movement in a coincidence anticipation tas k were studied using an erroneous knowledge of results (KR) paradigm. Forty participants received either no KR, correct KR,erroneous(+100 ms )KR, or 100 trials of correct KR followed by 50 trials of erroneous KR Kinematic analyses revealed that for this 100-50KR group the extensio n part of the movement was temporally adjusted under the influence of erroneous KR. Although accompanied by a decrease in movement amplitude , this did not account for the temporal shift in movement outcome, bec ause all groups showed a reduction in amplitude. It is argued that cha nging external time constraints mainly results in temporal adaptations . However, spatial adaptations do play a role in kinematic changes dur ing acquisition.