Fig. 3: Properties of double-peaked neurons in response to the DMR stimulus.

Three representative double-peaked neuron responses (a–c) are illustrated. Each row was obtained from a different animal. a All STRFs showed double-peaked responses at ~12.3 kHz and ~20.0 kHz with a ratio of 1.63 and had a bandwidth of ~0.98 octaves. The number of peaks included in computing each STRF was 1147 for spikes, 660 for large PSPs, 1361 for small PSPs, and all number of peaks for all events. b The PSP STRFs showed double-peaked responses at ~12.6 kHz and ~19.4 kHz with a ratio of 1.54 and had a bandwidth of ~0.94 octaves. The number of peaks included in computing each STRF was 1220 for spikes, 1591 for large PSPs, 1215 for small PSPs, and all number of peaks for all events. c The spike STRF had double-peaked responses at ~9.3 kHz and ~20.2 kHz with a ratio of 2.17 and a bandwidth of ~1.36 octaves. The number of peaks included in computing each STRF was 1028 for spikes, 424 for large PSPs, 708 for small PSPs, and all number of peaks for all events. d Quantification of double-peaked responses. e Harmonically related double-peaked responses. Each bar graph shows raw frequency ratios added to counting. Ratios were estimated from STRFs for all events. f The bandwidth comparison between single-peaked and double-peaked neurons. STRF bandwidths were estimated from all events. The lower and upper hinges are at the 25 (Q25) and 75 (Q75) percentiles, respectively. The median bandwidth values, the middle line between hinges, were 0.28 for single-peaked neurons and 0.96 for double-peaked neurons. The lower and upper inner fences are set at Q25 − 1.5×(Q75 − Q25) and Q75 + 1.5×(Q75 − Q25), respectively. Outliers beyond inner fences are indicated by asterisks.