Figure 9. (A) Pre- and post-exposure frequency-threshold tuning curves from a neuron in the inferior colliculus. Neuron was exposed for 20 minutes to a 16.1 kHz tone at a level of 107 dB SPL. Note dramatic expansion of the excitatory response area along the low-frequency tail of the tuning curve. Traumatising exposure had no effect on CF-threshold of the tip of the tuning curve. (B) Pre- and postexposure discharge rate-level function near CF. Note significant increase in the post-exposure discharge rate (from Salvi et al., 1996 with permission).