Fig. 5.

Emergent representation of sound class during behavior. (A) Average fraction change in raw neural response to target (black) and reference (gray) during approach behavior, grouped by BF-target frequency distance (n = 270 neurons with both reference and target data collected during passive listening and behavior). Neurons with BF within 0.1 octave of target frequency showed decreased target vs. reference responses (*P < 0.01), whereas other neurons showed no consistent target response change. Reference responses tended to increase, regardless of BF. (B) Change in raw response during avoidance, plotted as in A (n = 174). Average target responses increased for BF within 0.1 octave of target, whereas reference responses tended to decrease for all neurons. Changes in both A and B are consistent with enhanced reference-target discriminability. (C) Performance of a linear decoder trained to discriminate reference and target sounds from neural responses during approach behavior (red) and passive listening (green, n = 270). Crosses indicate average fraction of correct classifications as a function of the number of neurons in the decoder, fit by a decaying exponential (dashed lines). On average, 11.2 neurons were required to achieve 90% accuracy during behavior, and 16.0 were required during passive listening (bars, Lower, P < 0.001). (D) Performance of a linear decoder trained on avoidance data, plotted as in C (n = 151). During behavior, an average of 13.6 neurons was required to achieve 90% accuracy, and an average of 19.2 was required during passive listening (P < 0.001).