Figure 2.

Variation over time after furosemide injection in threshold tuning curves (left) and suprathreshold temporal coding (right) of a representative AN fiber. TFS and ENV coding remain tuned near CF during moderate MHL. Severe MHL, during which CF thresholds exceed 70 dB SPL, introduces pathological coding of low-frequency TFS. CF, threshold, and TTR are given for tuning curves and BF for suprathreshold TFS/ENV coding as in Figure 1. Spontaneous rate decreased from 76.6 to 2.2 spikes/s after furosemide injection before increasing to 10.6 spikes/s after 21 min of recovery. Lower spontaneous rate near the end of the recovery period in this fiber (bottom row) may explain the slight enhancement of CF-tuned TFS/ENV coding compared with control data. n.s., not significant.