Fig. 7.

Cross-correlograms for neuron pairs in ABL showing correlated activity within the intertrial intervals during the early and late phases of precriterion training, during postcriterion performance, and after reversal. A, Examples of neuron pairs with short latency interactions (0–2 msec).B, Example of neuron pair with longer latency interactions (2–10 msec). Values are shown in spikes per 1 msec bin, and the horizontal dashed lines on each correlogram designate the upper confidence limit (p < 0.01) for the interactions (see Materials and Methods). Precriterion training is divided into an early and late phase, and data from reversal training are shown for neuron pairs recorded during reversal sessions. Note that the confidence limit varies somewhat between graphs in some cases, reflecting small changes in firing rate. Although these changes were minimal, they were incorporated into the calculations of efficacy.