Figure 7. Simulation of the effect of V2 inactivation.

(A) Correlation structure of inputs from V1 to MT. MT neurons sorted by preferred motion direction.

(B) Correlation structure of inputs from V2 to MT. Since MT neurons are sorted by preferred direction, and since we assumed no systematic relationship between direction and disparity tuning in MT, the limited-range correlation structure with respect to disparity (analogous to the one with respect to motion direction in A) is shuffled in this view.

(C) Resulting input correlation structure to MT in the control condition. During cooling, the influence of V2 decreases, and with complete cooling, the total input correlations to MT are identical to those provided by V1 shown in A.

(D) Read-out weights depend on the preferred stimulus in each of the motion and depth tasks (different for each task) such that most informative neurons are preferentially read out. Qualitatively identical results are obtained in panels E and F for random weights, and optimal weights (see also Figure S5).

(E) Motion DP change due to cooling. Blue: simulation, red: analytical approximation.

(F) Depth DP change due to cooling. For simulation parameters see Experimental Procedures. For DP calculations we assume the total input correlations to MT to be equal to the response correlations since the effect of the decrease in firing rate on output correlations is small in our data.