LEARNING-DEPENDENT DENDRITIC HYPERTROPHY OF CEREBELLAR STELLATE CELLS- PLASTICITY OF LOCAL CIRCUIT NEURONS

Recent work has shown that motor learning, but not mere motor activity , changes the morphology of Purkinje cells, the major projection neuro ns of the cerebellar cortex. In the present study we examined how moto r skill learning affects the dendritic morphology of the stellate loca l circuit neurons. Adult female rats were either trained to complete a complex motor learning task or forced to traverse a flat, obstacle-fr ee runway. Golgi impregnated stellate cells were then traced via camer a lucida and their dendritic arborizations examined with a concentric ring analysis. Results showed the motor learning animals to have signi ficantly greater stellate cell dendritic arborizations than the activi ty controls. Thus these local circuit neurons exhibit morphological pl asticity. (C) 1997 Academic Press.