Fig. 3. Hypothesized interactions between early (V4) and late (IT) regions along the ventral visual stream as processing unfolds.

We hypothesize how stimulus and object-class information propagate between V4 and IT over time. At t₀, the forward pass reaches IT from V4, with V4 activity reflecting low-level stimulus properties but little information about object class. At t₁, object-class information from IT flows back to V4, increasing its task-relevant activity, which, in turn, influences IT at t₂. Notice that later in processing, V4 reflects object class information, but most of its activity remains tied to bottom-up stimulus properties. These hypothesized interactions would reconcile our results (Fig. 2) based on task-relevant information with previous results based on shared variance.