Comparison of the choice and time indices.

<p>A. The choice index (I_c – green lines) and time index (I_t – blue lines) in the first two sessions after reversal. The data points represent 50 successive and non-overlapping trials in a session. Data are averaged across all four rats. The time index passes 0 before the choice index, indicating that time spent at the high reward spout exceeds time spent at the low reward spout, long before the high reward spout is chosen more frequently.