Authors:

LAWSON, R.P, CALDER, A.J.

Reference:

Year of publication:

2007

CBU number:

6838

Abstract:

Behavioural adaptation has demonstrated the existence of distinct populations of cells which respond to different directions of seen gaze (Jenkins, Beaver & Calder, 2006) and head direction (Fang & He, 2005). The question of how these cells are coding information about direction of eye gaze has recently been addressed (Calder, Jenkins, Cassel & Clifford 2007), providing evidence for a multichannel system – with separate pools of cells tuned to different gaze directions, over an opponent-coding system - one pool broadly tuned to leftward and another to rightward gaze. Here we use adaptation to address whether head direction is coded by an opponent or multichannel system. Simultaneous adaptation to left and right orientated heads resulted in a miss-categorisation of left and right orientations as direct. Conversely, adapting to direct facing heads increased accuracy in perception of left and right head orientations. Opponent-coding predicts no effect of adaptation therefore our findings suggest that the visual representation of head direction is coded by a multichannel system.