Processing of motion boundary orientation in macaque V2

Heng Ma,Jiaming Hu,Haidong D Lu,Qianling Song,Xingya Cai,Pengcheng Li

doi:10.7554/elife.61317

Abstract

Human and nonhuman primates are good at identifying an object based on its motion, a task that is believed to be carried out by the ventral visual pathway. However, the neural mechanisms underlying such ability remains unclear. We trained macaque monkeys to do orientation discrimination for motion boundaries (MBs) and recorded neuronal response in area V2 with microelectrode arrays. We found 10.9% of V2 neurons exhibited robust orientation selectivity to MBs, and their responses correlated with monkeys' orientation-discrimination performances. Furthermore, the responses of V2 direction-selective neurons recorded at the same time showed correlated activity with MB neurons for particular MB stimuli, suggesting that these motion-sensitive neurons made specific functional contributions to MB discrimination tasks. Our findings support the view that V2 plays a critical role in MB analysis and may achieve this through a neural circuit within area V2.

Highlights

It is an important task to recognize an object when it is in motion
In non-human primates, it has been shown that neurons selective for the orientations of motion boundaries (MBs) are located in the ventral visual pathway (Marcar et al 2000; Mysore et al 2006; Chen et al 2016), but not in the dorsal pathway
Neurons have smaller RFs, stronger surround modulation and higher sensitivity to motion contrast (Hu et al 2018). These neurons are suitable for figure-ground segregation and/or MB detection (Chen et al 2016, Hu et al 2018). These findings suggest that V2 may calculate the MB orientation using a local DS-to-MB circuit

Summary

Introduction

It is an important task to recognize an object when it is in motion. Humans and non-human primates have an excellent ability in detection of motion boundaries (MBs)(Regan et al 1986, 1989). Other visual areas, including V3 and V4, have strong responses to MB (Zeki et al.2003; Mysore et al 2006). It is unclear whether all these areas contribute to the eventual perception of MBs. It is unclear whether all these areas contribute to the eventual perception of MBs This question is important for V2 since it is the lowest area in the visual processing hierarchy that possesses MB sensitivity

Results

Discussion

Conclusion