Visual Motion Processing in Macaque V2

Abstract

Graphical Abstract Highlights d DS neurons in a non-dorsal visual area (V2) were studied with map-guided recordings d V2 DS neurons exhibit features distinct from the DS neurons in the dorsal area MT d Clusters of V2 DS neurons form functional architectures sensitive to motion contrast d Response properties of V2 DS neurons are suitable for figureground segregation SUMMARY In the primate visual system, direction-selective (DS) neurons are critical for visual motion perception. While DS neurons in the dorsal visual pathway have been well characterized, the response properties of DS neurons in other major visual areas are largely unexplored. Recent optical imaging studies in monkey visual cortex area 2 (V2) revealed clusters of DS neurons. This imaging method facilitates targeted recordings from these neurons. Using optical imaging and single-cell recording, we characterized detailed response properties of DS neurons in macaque V2. Compared with DS neurons in the dorsal areas (e.g., middle temporal area [MT]), V2 DS neurons have a smaller receptive field and a stronger antagonistic surround. They do not code speed or plaid motion but are sensitive to motion contrast. Our results suggest that V2 DS neurons play an important role in figure-ground segregation. The clusters of V2 DS neurons are likely specialized functional systems for detecting motion contrast.

Integration of Motion and Form Cues for the Perception of Self-Motion in the Human Brain

“…Combining the results from the three experiments, we found that the early visual areas V1, V2, and V3 (V3v and V3d combined) respond to a position shift of the FoE defined by either motion or form cues. This is consistent with the findings of primate neurophysiology studies showing that these areas process both local motion and form information (Hubel and Wiesel, 1968;Mikami et al, 1986;Felleman and Van Essen, 1987;Levitt et al, 1994;Gegenfurtner et al, 1997;Hu et al, 2018). Research identifying the homology of primate areas V1, V2, and V3 in the human brain has been quite successful and shows that these areas in humans are organizationally and functionally analogous to those in macaques.…”

Columnar connectome: toward a mathematics of brain function

“…This “real-to-illusory” higher order transformation must be mediated by the anatomical connectivity between V1 and V2. Specifically, we observe establishment of modality-specific higher order properties in different stripes of V2: (a) thin stripes : color representation in V1 blobs, which is dominated by red-green/blue-yellow axes, transforms to a multicolor map of hue columns in V2 (Conway, 2001; Xiao et al, 2003); (b) thin stripes : luminance encoding in V1 transforms to brightness encoding in V2 (Roe et al, 2005); (c) thick/pale stripes : encoding of simple contour orientation transforms to higher order cue-invariant orientation representation in V2 (Rasch et al, 2013); (d) thick stripes : simple motion direction detection transforms to the detection of coherent motion in V2 (useful for figure-ground segregation, Peterhans and von der Heydt) and to motion contrast defined borders (Hu et al, 2018); and (e) thick stripes : segregated representation of left and right eyes in V1 to maps of near-to-far binocular disparity columns in V2 (Chen et al, 2008, 2017). Touch : In a similar vein, in somatosensory cortex, integration of tactile pressure domains in area 3b (Friedman et al, 2004) are hypothesized to generate motion selectivity domains in area 1 (Pei et al, 2010; Wang et al, 2013; Roe et al, 2017).…”

Spatial suppression promotes rapid figure-ground segmentation of moving objects

“…Theoretical work shows that this sensitivity to small moving stimuli paired with insensitivity to wide-field, uniform motions is well suited to support segmentation of moving figures from their backgrounds 13,16–18 . However, direct behavioral evidence for this link is lacking, and even indirect neurophysiological evidence is limited 12,19–21 . In fact, motion segregation could be accomplished by specialized processes not involving center-surround mechanisms 22 , with center-surround mechanisms playing a role in other visual processes, including redundancy reduction, input normalization, estimation of optic flow, heading direction, 3D shape-from-motion, and detection of edge discontinuities 23–30 .…”