Primate extrastriate cortical area MST: a gateway between sensation and cognition.

Benedict Wild,Stefan Treue

doi:10.1152/jn.00384.2020

Abstract

Primate visual cortex consists of dozens of distinct brain areas, each providing a highly specialized component to the sophisticated task of encoding the incoming sensory information and creating a representation of our visual environment that underlies our perception and action. One such area is the medial superior temporal cortex (MST), a motion-sensitive, direction-selective part of the primate visual cortex. It receives most of its input from the middle temporal (MT) area, but MST cells have larger receptive fields and respond to more complex motion patterns. The finding that MST cells are tuned for optic flow patterns has led to the suggestion that the area plays an important role in the perception of self-motion. This hypothesis has received further support from studies showing that some MST cells also respond selectively to vestibular cues. Furthermore, the area is part of a network that controls the planning and execution of smooth pursuit eye movements and its activity is modulated by cognitive factors, such as attention and working memory. This review of more than 90 studies focuses on providing clarity of the heterogeneous findings on MST in the macaque cortex and its putative homolog in the human cortex. From this analysis of the unique anatomical and functional position in the hierarchy of areas and processing steps in primate visual cortex, MST emerges as a gateway between perception, cognition, and action planning. Given this pivotal role, this area represents an ideal model system for the transition from sensation to cognition.

Highlights

Primate cortex consists of well over 100 different areas that can be differentiated on anatomical as well as physiological grounds [1,2,3,4,5]
Once visual information coming from the lateral geniculate nucleus (LGN) has arrived in layer 4C of the six-layered primary visual cortex (V1), a hierarchy of brain areas can be determined based on the cortical layers from which projections originate and in which they terminate
This speaks for a role of MSTd in the perception of self-motion, as a forward movement through the environment results in an optic flow pattern that is dominated by an expanding component. This tuning is independent of the exact shape of the stimulus, that is, the preferred direction in spiral space is the same for random dot patterns (RDPs) and filled or empty squares [40]. These results suggest that MSTd contains a population of cells tuned to spiral motion directions with their respective preferred directions distributed in spiral space, similar to linear motion preferences in earlier visual areas

Summary

INTRODUCTION

Primate cortex consists of well over 100 different areas that can be differentiated on anatomical as well as physiological grounds [1,2,3,4,5]. Future work on the neural underpinnings of motion perception should embrace the idea of a network of areas, rather than a unidirectional processing pipeline This first section focused on MST with regard to features that are typically discussed in other visual areas, such as receptive field size, tuning for direction and speed, or relation to behavior in simple discrimination tasks. To test whether MSTd neurons represent the current heading direction, Duffy and Wurtz [105] presented monkeys with radial and rotational stimuli that differed in the location of their center of motion They found that in most neurons the response varied with the location of the center of motion (Fig. 7) and that the preferred centers of motion were topographically distributed across the visual field [see Gu et al [106], Lappe et al [107] Page and Duffy [108], Pekel et al [109] for similar findings).

E Rightward

Findings

CONCLUSIONS