The Effects of Interrupted Noise Exposures on the Noise-Damaged Cochlea

Details

• Personal Author:
  Ahroon WA ; Hamernik RP
• Description:
  A variety of interrupted noise exposure paradigms will produce a toughening effect in the mammalian auditory system. That is, the threshold shift will gradually become smaller with each successive daily exposure. The ability of the system to be toughened has not been explored in subjects with a pre-existing noise-induced hearing loss. Using the chinchilla as the experimental animal, evoked potential audiometry to obtain thresholds, and surface preparation histology to quantify the sensory cell population, the issue of toughening was examined in the noise-damaged auditory system. Toughening was produced by a 1.0 kHz, narrow-band impact at 115 dB peak SPL for 10 days, 6 h/day, and trauma was produced by a 1.0 kHz, narrow-band impact at 121 dB peak SPL for 5 days, 24 h/day. Four groups of animals were used. Group 1: traumatic exposure followed 30 days later by the toughening exposure. Group 2: toughening exposure followed 30 days later by the traumatic exposure. Group 3: a trauma-only control. Group 4: a toughening-only control. Group 2 that received the toughening exposure 30 days prior to the traumatic exposure showed a 10 to more than 20 dB toughening effect between the 0.5 and 4.0 kHz test frequencies, while Group 1 that received the traumatic exposure followed 30 days later by the toughening exposure showed no toughening. The permanent changes in the evoked response audiograms and sensory cell populations were the same in Groups 1, 2 and 3 that were exposed to the traumatic noise, regardless of whether or not the animals were ever subjected to the toughening noise or whether the toughening noise preceded or followed the traumatic noise. [Description provided by NIOSH]
• Subjects:
  Animals Ear Hearing Loss Hearing Loss, Noise-Induced Noise Noise, Occupational Occupational Health Safety Sense Organs
• Keywords:
  Animal-studies Cell-damage Ear-disorders Hearing-loss Impulse-noise Industrial-noise Noise-exposure Noise-induced-hearing-loss
• ISSN:
  0378-5955
• Document Type:
  Text
• Funding:
  Grant
• Genre:
  Journal Article
• Place as Subject:
  New York ; OSHA Region 2
• CIO:
  National Institute for Occupational Safety and Health (NIOSH)
• Topic:
  Workplace Safety & Health
• Location:
  North America
• Pages in Document:
  103-109
• Volume:
  143
• Issue:
  1
• NIOSHTIC Number:
  nn:20029779
• Citation:
  Hear Res 2000 May; 143(1-2):103-109
• Contact Point Address:
  Auditory Research Laboratory, Plattsburgh State University of New York, 107 Beaumont Hall, 101 Broad Street, Plattsburgh, NY 12901-2681
• Federal Fiscal Year:
  2000
• Performing Organization:
  Plattsburgh State University, New York
• Peer Reviewed:
  True
• Start Date:
  19860301
• Source Full Name:
  Hearing Research
• End Date:
  20130514
• Collection(s):
  National Institute for Occupational Safety and Health
• Main Document Checksum:
  urn:sha-512:520c53d404b53d0e9729b22ab0a8c08b6a04091f5f769090bde0ab35daa5984e4b1ea76ce7ab4053743dfff8455828a001fb59b89da1f15b85b5e9fa9d9b9320
• Download URL:
  https://stacks.cdc.gov/view/cdc/190689/cdc_190689_DS1.pdf
• File Type:
  [PDF - 374.94 KB ]