FIG. 6.

DPOAE threshold for 2f1–f2 (A) and f2–f1 (B). Awake (grey), anaesthetised (black). Error bars: absolute value of SD, shown for graphical reasons only as upward (anesthetised) or downward bar (awake). A: In awake bats, 2f1–f2 DPOAE threshold was between 8.7 and 17.5 dB SPL for f2 between 20–90 kHz. Under anaesthesia, the threshold was more insensitive for frequencies above 40 kHz. B For the f2-f1 DPOAE, minimum thresholds were about 6 dB SPL at 50–55 kHz. During anaesthesia, the threshold minimum shifted to 40 kHz. Statistical analysis: two-way ANOVA with p values adjusted for multiple comparisons according to the Bonferroni–Holm correction.