Abstract
To assess the effect of behavioral manipulation as therapy on the new neural network after brain damage, we studied the effect of skilled training on neurophysiological change in the intact cortex after unilateral damage to the forelimb sensorimotor cortex. Eighteen male Wistar rats (4-5 months) were assigned to 6 groups: (1) rats receiving unilateral forelimb sensorimotor cortex lesion (FSMC lesion) and postoperative training on the skilled task (L-skilled), (2) rats with unilateral FSMC lesion receiving simple repetitive task (L-simple), (3) rats with unilateral FSMC lesion receiving no task (L-non-training), (4)sham-operated rats receiving skilled task, (5) sham-operated rats receiving simple task, (6) sham-operated rats with no task. Rats were anesthized with halothene and followed with Ketamine HCI and electrical lesion was added at FSMC where was confirmed by electrical microstimulation (less than 20 μA). After chronic operations, rats were trained according to each task. Recovery of motor behavior was tested by the symmetry in the use of the forelimbs for upright postural support. Recovery from the asymmetrical use in the forelimbs indicated the recovery period was faster in the L-skilled and L-simple than L-non-training groups. Microstimulation mapping showed forelimb area was expanded in intact cortex of the L-skilled group especially. These findings suggested that therapeutic effect as behavioral manipulation makes neurophysiological change in whole brain, evening the intact side, after unilateral cortical lesion.
