ABR threshold shifts after implantation at 1, 2, 6, and 16 kHz for animals in the CAES (a) and NS (b) groups. Threshold shifts ranged from 0-45 dB at 6 kHz and 0-55 dB at 16 kHz. Five CAES animals showed greater than 10 dB ABR threshold shift at 16 kHz after surgery (n1, n5, n24, n25, and n27) and three NS animals showed greater than 10 dB of threshold shift at 16 kHz after surgery in the NS group (n9, n15, and n26).