128 — A Sensorimotor Circuit in Mouse Cortex for Visual Flow Predictions

Leinweber et al (10.1016/j.neuron.2017.08.036)

Read on 26 December 2017
#neuroscience  #vision  #sensation  #visuomotor  #circuit  #visual-flow 

“Visual flow” describes the ability of most sighted animals to make educated predictions about the movement of stimuli across the visual field. For example, if you see a car driving down a street, you can predict the next likely location of the car based on where it is now and where it was previously.

Likewise, many species can “anticipate” the relative motion of stimuli when it is the organism that is moving, not the stimulus. (For example: The car is parked, and you can keep your eyes focused on the car as you turn your head past it.)

Though this effect is well studied, the cellular mechanisms for visual flow have been difficult to pin down precisely. In this study, Leinweber et al demonstrate that neurons in mouse brain areas A24b (a part of the anterior cingulate cortex) and M2 (a component of mouse motor cortex) send data back to primary visual cortex (V1) that helps “predict” the logical movement of stimuli based on the endogenous movements and locomotion of the mouse.

Layer 2/3 of mammalian sensory cortices is known to be responsible for detecting mismatches between predicted and actual sensory stimuli; so it is no surprise that these visuomotor connections enter V1 and synapse in this depth of cortex.

By placing the target mouse in a 2D simulation of a maze, it was possible to detect use of this circuitry as the mouse made conscious movements through its environment. When the experimenters reversed the relationship between the mouse’s movements and the direction shown on screen and trained the mouse again — simply, the mouse was moving in a “mirror world” — these connections appeared to reconfigure as the mouse learned about its new visual world.