Fig. 3.

Long-term hearing loss increases intrinsic excitability of AI pyramidal neurons. A: voltage responses to current injection recorded from layer II/III pyramidal neurons of the auditory cortex. B: membrane properties of AI pyramidal neurons: resting membrane potential (RMP; i), response threshold (ii), and input resistance (iii). Only input resistance in the higher-CF area significantly increased. C: threshold of minimal current injected to activate spikes in the pyramidal neurons. D: number of spikes as a function of current amplitude. The number of spikes increased in the higher-CF area, but not the lower-CF area, of the NIHL animals (see text for statistical tests). *P < 0.05; n.s., not significant. Numbers in Bi indicates numbers of cells tested.