After providing an anatomical overview, she reviewed the well known motor functions of the different deep nuclei. The dentate nucleus (cerebro-cerebellum), which is the largest and connected to the cerebrum, works as a comparator that generates an error signal and provides planning and timing information.The other nuclei - Fastigious, emboliform and globase (spino-cerebellum) - have output to the spinal tracts and is involved in fine movements. The vestibulo cerebellum is involved in posture maintenance and eye movements.
The Mossy fibers (from the vestibular nuclei) and the climbing fibres (from the inferior olive) both provide input the Purkinje fibres. The former provide input on the context and the latter forms the error signal. Interestingly, Long Term Depression (LTD) which forms the memory element of the cerebellar motor learning, happens when both these fibre tracts are simultaneously active. If only one these fibre pathways are active, LTP (Long Term Potentiation) ensues. Therefore the cerebral cortex and the cerebellum have different mechanisms for LTP and LTD.
Suwarna then reviewed a number of studies evaluating cognitive functions and cerebellum. These included attention, working memory and spatial memory in various animal models (eg: pcd - purkinje cell degeneration model).