Laboratory

in sensory physiology

Neurons in extrastriate visual area V5/MT are tuned to conjunctions of binocular 3D depth and direction of motion. Based on these properties, their signals correlate with perceptual switches in bistable structure-from-motion figures (Dodd et al. 2001). Neurons with the same stimulus selectivity are clustered (Albright et al 1984; DeAngelis & Newsome 1999). Different studies, psychophysical and neuronal, have postulated that specific intrinsic connectivity in V5/MT underlies the emergence of such signals (Bradley et al., 1998; Nawrot & Blake 1991). We have shown that long range connectivity in V5/MT is highly patterned, consistent with specific connectivity between functionally distinct depth and direction columns (Ahmed et al 2012). We are currently investigating the nature and specificity of neuronal connections within and between visual areas in relation to their functional properties.

Picture above shows a cortical V5/MT injection of CTb labeling a column of neurons (Ahmed et al 2012)