{"data":[{"source":"bio.acousti.ca","id":"57600","type":"article","title":"Long-term evidence of noise-induced permanent threshold shift in a harbor seal ( Phoca vitulina )","author":"Reichmuth, Colleen; Sills, Jillian M.; Mulsow, Jason; Ghoul, Asila","editor":null,"year":"2019","month":null,"journal":null,"booktitle":null,"series":null,"howpublished":null,"volume":null,"number":null,"pages":null,"chapter":null,"edition":null,"publisher":null,"organization":null,"institution":null,"school":null,"address":null,"type_of_work":null,"note":null,"isbn":null,"issn":null,"doi":"10.1121\/1.5129379","url":"http:\/\/asa.scitation.org\/doi\/10.1121\/1.5129379","attachments":"https:\/\/bio.acousti.ca\/sites\/default\/files\/reichmuth2019.pdf","keywords":null,"abstract":"In psychophysical studies of noise-induced hearing loss with marine mammals, exposure conditions are often titrated from levels of no effect to those that induce significant but recoverable loss of auditory sensitivity [temporary threshold shift (TTS)]. To examine TTS from mid-frequency noise, a harbor seal was exposed to a 4.1-kHz underwater tone that was incrementally increased in sound pressure level (SPL) and duration. The seal's hearing was evaluated at the exposure frequency and one-half octave higher (5.8 kHz) to identify the noise parameters associated with TTS onset. No reliable TTS was measured with increasing sound exposure level until the second exposure to a 60-s fatiguing tone of 181 dB re 1 \u03bcPa SPL (sound exposure level 199 dB re 1 \u03bcPa2s), after which an unexpectedly large threshold shift (>47 dB) was observed. While hearing at 4.1 kHz recovered within 48 h, there was a permanent threshold shift of at least 8 dB at 5.8 kHz. This hearing loss was evident for more than ten years. Furthermore, a residual threshold shift of 11 dB was detected one octave above the tonal exposure, at 8.2 kHz. This hearing loss persisted for more than two years prior to full recovery.","type_name":"Journal Article","journal_abbreviation":null,"pmid":null,"info_url":"https:\/\/bio.acousti.ca\/node\/57600"}]}