The importance of MF-GC synaptic diversity for multisensory information processing in the CC
The GC layer of the CC is thought to pre-process incoming mossy fiber (MF) activity so that PCs can more easily distinguish distinct patterns associated specific sensory contexts. The precise combination of internal and external sensory cues indicates a sensory motor state that is then “learned” by association with a feedback signal (supervised learning), in order to fine tune motor movements and cognitive functions. But how the input-specific properties of MF-GC synapses that we recently identified contribute to multisensory stimulus representation and CC computations is not known. In order to formulate specific hypothesis regarding how synaptic diversity and interneuron dendritic integration might influence CC circuit function, we are examining the impact of synaptic diversity on network models and aim to predict future measurements of the critical cellular components of the cerebellar netowork.
Chabrol, F.P., Arenz, A., Wiechert, M.T., Margrie, T.W., and DiGregorio, D.A. (2015). Synaptic diversity enables temporal coding of coincident multisensory inputs in single neurons. Nature neuroscience 18, 718-727.
Summary: Synaptic strength and dynamics is diverse across synapse types, however it is not known how circuits might take advantage of this diversity for specific computations. In this study we demonstrated that synaptic response diversity reflects the diversity of sensory information entering the cerebellum, and enables a novel temporal coding scheme for multisensory inputs (Chabrol et al., 2015).