217 — The Circuit Motif as a Conceptual Tool for Multilevel Neuroscience

Braganza & Beck (10.1016/j.tins.2018.01.002)

Read on 25 March 2018
#neuroscience  #graphs  #motif  #connectome  #brain-function  #brain-map  #computation 

I wrote earlier last month about one specific motif that is found in multiple species. This paper points to that motif alongside a whole variety of other common neuronal circuits, and explains how learning about these motifs can teach us about neural computation as a whole.

Much like the mutual lateral inhibition circuit in that earlier paper, the paper lists other examples of simple (i.e a small number of acting neuron components) circuits that combine excitatory and inhibitory inputs in a complex way.

The reason we know about these motifs at all is generally a result of functional imaging, because the nanometer-resolution required to establish “drag-net” anatomical evidence across the entire brain is not quite technologically feasible and affordable yet. But we can’t necessarily rely on functional (e.g calcium imaging) analyses alone to identify these circuits, as these data may obscure the actual connectivity of neurons (for example, if a particular synapse is not active during recording).

Understanding these motifs will help us understand the computational primitives of the brain, which will in turn teach us about biological signal processing, and inform how we design BCIs.