Figure 3.

Scatter plots of information about firing rate from position, versus velocity, versus full filtered signal . Each dot corresponds to the information measured from a single cell (bits per second, measured in 5 msec bins); diagonal line indicates unity. Information estimates in the left and middle panels fall significantly above diagonal, indicating more information provided by optimal than by position or velocity alone. Position was sampled at zero time lag here, with velocity sampled at 100 msec after the current firing rate time bin (lag values chosen to maximize the information values shown; for other time lags, these points tended to fall even farther above the diagonal).