Auditory Cortex Basal Activity Modulates Cochlear Responses in Chinchillas
Figure 4
Sound pressure and frequency dependencies of CAP and CM amplitude changes after cortical deactivation with lidocaine.
Each column corresponds to one experiment. The upper and lower rows display CAP and CM amplitude changes (dB) respectively. Data were acquired up to 80 minutes after the lidocaine microinjection. Green color represents no amplitude changes (±1.0 dB in CAP and ±0.5 dB in CM); blue and violet represent significant decreases; while red and yellow, significant increases. Experiment cx_rw_12: Significant reductions in CAP and CM (t = 2.84, p<0.05 and t = 2.81, p<0.05 respectively) were obtained at frequencies between 2–4 kHz. Experiment cx_rw_07: Significant CAP and CM reductions (t = 3.36, p<0.05 and t = 2.81, p<0.05 respectively) were obtained at frequencies between 2–3 kHz. Experiment cx_rw_09: Significant CAP reductions and CM augmentations (t = 4.34, p<0.01 and t = −2.67, p<0.05 respectively) were obtained at 5 kHz and between 5–6 kHz correspondingly. Experiment cx_rw_08: Significant increases in CAP and CM (t = −3.14, p<0.05 and t = −3.34, p<0.01 respectively) were obtained at frequencies of 7–8 kHz. Note that in the two left columns (Exp_ID: cx_rw_12 and cx_rw_07) CAP and CM reductions are greatest for 2–4 kHz frequencies, while small areas of either increase or decrease can be observed in the two right columns (Exp_ID: cx_rw_09 & cx_rw_08) at frequencies higher than 4 kHz.