In other auditory impairments such as acute acoustic trauma, deafness, or tinnitus, hyperexcitability may be the result of reduced (tonic) inhibitory strength (see Box 3) following less-developed or impaired fast auditory processing and subsequent failure to recruit BDNF and PV-IN dependent increased central neural gain (see Section “Altered Excitation and Inhibition in Acute Acoustic Trauma, Deafness, and Tinnitus: Lost Fast Auditory Processing”). This evidence concerns the gene BDNF and deafness.