Dynamics of population coding for object views following object discrimination training

Abstract

We have previously demonstrated that inferotemporal neurons respond to objects viewed from a range of angles, even without any prior experience in learning the associations among the views. Several models have been proposed to explain object recognition across disparate views. However, direct neuronal evidence is rare. In the present study, we focused on the response similarity of a population of inferotemporal cells to object views, following different prior experiences. Two monkeys were subjected to a task in which object discrimination across views was required. We found significantly higher neural response similarity to 30° separated views, 190ms after object image presentation, than without any prior discrimination experience across views. The time period over which the similarity was significant began and endured similarly for 60° separated views at 190–850ms. For 90° separated views, the time period over which the similarity was significant was shorter and started later, at 230–550ms. The results demonstrate the dynamics of cell population activity and suggest a possible explanation for object recognition across disparate views.