Figure 2.

Examples of FM rate selectivity in pup cortex. The panels on the top and bottom show response to changing FM sweep duration and rate, respectively. A, B, A neuron from a 14-d-old pup that exhibited FP-type selectivity for FM rate. The duration functions (A) obtained at two different FM BWs do not overlap, but FM rate functions (B) obtained by dividing the BW of the sweep by the duration of the sweep do. This suggests that this neuron was selective for FM rate and not duration. C, D, A neuron from a 17-d-old pup that had BP selectivity for FM rate. E, F, A neuron from a 21-d-old pup that was nonselective for FM rate. The response of the neuron to different FM rates tested was within 50% of maximum response. The different symbols denote different FM sweep BWs tested.