The cerebellum (Latin: little brain) may be small by name, but it has almost 80% of the neurons of the brain, and it is densely connected with both sub-cortical and cortical structures. Yet, in part due to the perceived challenge of monitoring cerebellar activity non-invasively, the cerebellum has attracted little attention in cognitive neuroscience and is often put aside as a locus of motor coordination rather than cognition. The presumed primitiveness of the cerebellum is reflected in the popular, but discredited idea of the cerebellum being a reptile brain. In part, the lack of attention to the cerebellum and the notion of the cerebellum being a primitive part of the brain, may be explained by a perceived impossibility of measuring its electrophysiology, such as by magnetoencephalography (MEG), as stated by textbooks.
The objective of this project is to make apparent that the understudied cerebellum is fully integrated in cognition, specifically by building sensory expectations. We propose that dysfunction of the cerebellum may underlie some of the symptoms we see in neurodegenerative diseases such as Parkinson’s disease and essential tremor. As an integral part of this endeavour, we intend to demonstrate that the cerebellum integrates with respiratory mechanisms to build sensory expectations, and that the cerebellum’s activity can be recorded using groundbreaking new electrophysiological methods. The working hypotheses of the RCB project are:
Hypothesis 1: The cerebellum performs sensory prediction by building sensory expectations to inform action. It does so in alignment with respiration and the sub-cortical structures of basal ganglia and thalamus.
Hypothesis 2: Based on newly developed magnetic sensors, optically pumped magnetometers (OPM), that provide feasible recordings of the spatiotemporal properties of the electrophysiological cerebellar signal, Parkinson’s disease patients and essential tremor patients will show cerebellar dysfunction when participating in paradigms that depend on correctly building sensory predictions?
The scientific perspective and relevance of the RCB project is that it will foster a comprehensive new outlook on the functions of the cerebellum, dispelling the notion of the cerebellum as only maintaining motor coordination and carrying out only primitive cognitive operations. Generally, it will bring researcher education up-to-date by emphasising how the cerebellum and its functions are intertwined with the rest of the brain in allowing for cognition; and specifically for researchers of electrophysiology, it will show that its electrophysiology can fruitfully be investigated non-invasively using groundbreaking new OPM sensors. Demonstrating this will help usher in a new generation of researchers who will be able to unravel the workings of the cerebellum and relating its and the brain’s processing to other bodily functions, such as respiration.
