Figure 6.

A) Proposed model for the relationship of physiological changes to recovery from the acute to the chronic stage, compatible with the present results. (B) A scheme depicting the possible roles in hand movement of primary and secondary motor areas of 1 hemisphere. The stroke scenarios are represented in the reorganized (chronic) state. Darker shading denotes greater involvement in movement of the affected hand. A stepwise recruitment of motor areas is depicted with increasing disruption of the corticospinal tract. Minor disruption (small stroke) results in the recruitment of perilesional M1, whereas more extensive disruption (large stroke) requires the use of secondary motor areas and even transcallosal inputs from the intact hemisphere. We propose that during the subacute stage after stroke a smaller or larger degree of intracortical disinhibition is necessary to maintain access to these additional networks, depending on the extent of disruption of the original corticospinal projection.