Towards unravelling brain information processing
The part of the brain known as the cerebellum is involved in motor coordination, and the maintenance of balance. It contains mossy fibres, which convey both sensory and motor signals, and integrate this information towards functional output. Mossy fibres communicate with Golgi cells and granule cells in the cerebellar granule cell layer, but the fine details of this connectivity remain poorly understood. The scope of the EU-funded MULTIMOSSY (Multimodal mossy fiber input and its role in information processing in the cerebellar granule cell layer) project was to characterise the anatomical connectivity and functional properties of mossy fibre inputs. Using optogenetics and electrophysiology, scientists activated mossy fibres and performed a functional mapping of the cerebellum by recording light-evoked synaptic responses in Golgi cells and granule cells. By doing so, they discovered differences in the amplitude and short-term dynamics of the mossy fibre synaptic inputs. In addition, their observations suggested that a combination of sensory information and motor commands are required to trigger a spike output in granule cells. Overall, the MULTIMOSSY work unveiled important information on the connectivity and properties of mossy fibre inputs. In particular, it helped us determine whether granule cells and Golgi cells function as unimodal or multimodal input integrators in the cerebellum. Collectively, this knowledge brings us a step closer to comprehending information processing in a major cortical structure in the mammalian brain.
Keywords
Brain, cerebellum, mossy fibres, Golgi cells, granule cells
