Figure 8.

Population data: ENV- and TFS-following responses. A, ENV-following response (peak height of Sumcor at zero delay) for all units. Seven unit types are shown: LF, PL, PN, CS, CT, and OC, and other onset types (including O, OI and OL). Three main categories of units are described in the legend: (1) primary-likes and low-frequency (including PL, PN and LF units), in white circles; (2) choppers (including CS and CT units), in gray triangles; and (3) onsets (including OC, O, OL, and OI units), in black squares. Asterisks indicate significant differences between Sumcor values of different unit types. B, TFS-following response (peak height of Difcor at zero delay) for all units. Same legend as for A. C, Ratio of XAC to SAC as a function of BF for all units recorded. A ratio of 0 indicates a purely TFS-following response and a ratio of 1 indicates s purely ENV-following response. D, Ratio of XAC to SAC as a function of Q10 (or Q_{10 dB}) calculated from the receptive fields for all units recorded. Small Q10 values indicate sharp filter bandwidths and larger Q10 values indicate broader filter bandwidth.