Collicular circuits supporting the perceptual, motor and cognitive demands of ethological environments

Abstract

Animals evolve to survive in their environment. Accordingly, a reasonable hypothesis is that brain evolution prioritises the processing of useful sensory information over complete representation of the surroundings. The superior colliculus or tectum is a brain area that processes the animal's surroundings and directs movements in space. Here, we review recent studies on the role of the superior colliculus to assess the validity of this "utility hypothesis". We discuss how the response properties of collicular neurons vary across anatomical regions to capture ethologically relevant stimuli at a given portion of the sensory field. Next, we focus on the recent advances dissecting the role of defined types of sensory and motor neurons of the colliculus in prey capture. Finally, we discuss the recent literature describing how this ancient structure, with neural circuits over 500 million years old, implements the necessary degree of cognitive control for flexible sensorimotor transformation.

Keywords: Cognition; Ethology; Flexible sensorimotor transformations; Neural circuits; Prey capture; Region-specific anatomical and functional properties; Sensory-motor processing; Superior colliculus; Tectum.