An integrative role for the superior colliculus in selecting targets for movements

Abstract

-A fundamental goal of systems neuroscience is to understand the neural mechanisms underlying decision making. The midbrain superior colliculus (SC) is known to be central to the selection of one among many potential spatial targets for movements, which represents an important form of decision making that is tractable to rigorous experimental investigation. In this review, we first discuss data from mammalian models-including primates, cats, and rodents-that inform our understanding of how neural activity in the SC underlies the selection of targets for movements. We then examine the anatomy and physiology of inputs to the SC from three key regions that are themselves implicated in motor decisions-the basal ganglia, parabrachial region, and neocortex-and discuss how they may influence SC activity related to target selection. Finally, we discuss the potential for methodological advances to further our understanding of the neural bases of target selection. Our overarching goal is to synthesize what is known about how the SC and its inputs act together to mediate the selection of targets for movements, to highlight open questions about this process, and to spur future studies addressing these questions.

Circuits for Action and Cognition: A View from the Superior Colliculus

“…This latter activation may enhance lateral inhibition (Binns & Salt 1997, Endo et al 2005, Lee et al 2001). Nicotine enhances the generation of express saccades when injected in monkey colliculus (Watanabe et al 2005), and activation of these cholinergic nuclei in smaller mammals produces orienting (Wolf et al 2015). It is unknown whether oscillations seen in the avian circuit appear in the mammalian colliculus, although there is some evidence that the relative timing of activity across the colliculus may signal information about orienting movements (Brecht et al 2004).…”

Warning! Dopaminergic Modulation of the Superior Colliculus

“…The functional role of these modulatory inputs, which are known to include GABAergic and cholinergic innervation, in influencing movement-related SC processing is an active area of investigation [2]. …”

The mouse cortico-tectal projectome

“…The SC is a complex laminar structure implicated in spatial attention, orienting, navigation, defense, and decision-making 1,12,13,42,43 . As a major site of multisensory integration from visual, auditory, and somatosensory modalities, it is critical for animals to filter overwhelming sensory input, align brainwide inputs, and guide behavior.…”