Journal Article

Gap Junctions May Have A Computational Function In The Cerebellum: A Hypothesis

Gilbert, Mike, Rasmussen, Anders

2024

Overview

In the cerebellum, granule cells make parallel fibre contact on (and excite) Golgi cells and Golgi cells inhibit granule cells, forming an open feedback loop. Parallel fibres excite Golgi cells synaptically, each making a single contact. Golgi cells inhibit granule cells in a structure called a glomerulus almost exclusively by GABA spillover acting through extrasynaptic GABA A receptors. Golgi cells are connected dendritically by gap junctions. It has long been suspected that feedback contributes to homeostatic regulation of parallel fibre signals activity, causing the fraction of the population that are active to be maintained at a low level. We present a detailed neurophysiological and computationally-rendered model of functionally grouped Golgi cells which can infer the density of parallel fibre signals activity and convert it into proportional modulation of inhibition of granule cells. The conversion is unlearned and not actively computed; rather, output is simply the computational effect of cell morphology and network architecture. Unexpectedly, the conversion becomes more precise at low density, suggesting that self-regulation is attracted to sparse code, because it is stable. A computational function of gap junctions may not be confined to the cerebellum.

• Publisher: Springer US,Springer Nature B.V
• Subject: Basic Medicine / Biomedical and Life Sciences / Biomedicine / Cell and Molecular Biology / Cell- och molekylärbiologi / Cells / Cerebellum / Computer simulation / Feedback / Gap junctions / Glomerulus / Golgi cells / Granule cells / Hypotheses / Medical and Health Sciences / Medicin och hälsovetenskap / Medicinska och farmaceutiska grundvetenskaper / Neurobiology / Neurology / Neuromodulation / Neurosciences / Neurovetenskaper / Physiology / Probability distribution / Receptor mechanisms / γ-Aminobutyric acid A receptors