Noise-Induced Hearing Loss in the Noise-Toughened Auditory System

Details

• Personal Author:
  Ahroon WA ; Hamernik RP ; Ahroon WA ; Hamernik RP
• Description:
  The auditory system, toughened by an interrupted noise exposure, has been shown in several reports to be less affected by (or protected from) a subsequent high-level noise exposure. Exposure to 115 dB peak SPL, 1 kHz narrow band (400 Hz) transients presented l/s, 6 h/day, to four groups of chinchillas produced a 10-28 dB toughening effect across the 0.5-8.0 kHz test frequency range. Following either a 30 day or an 18 h recovery period the animals were exposed to the same impulses but presented at 121 or 127 dB peak SPL for five uninterrupted days, thus producing an asymptotic threshold shift (ATS) condition. Comparisons between toughened and untoughened control subjects showed: (1) During the 121 dB exposure there was a statistically significant reduction of 10-25 dB in ATS across the entire test frequency range. Thirty days following the 121 dB exposure there were no significant differences in the postexposure permanent effects on thresholds and sensory cell loss. (2) During the 127 dB exposure only the group with the 30 day interval between the toughening and traumatic exposures showed a small (approximately 10 dB), statistically significant, frequency-specific (8 kHz), reduction in ATS. Thirty days following the 127 dB exposure a statistically significant protective effect on threshold was measured only at 16.0 kHz. However, both toughened groups showed less inner hair cell loss at and above 1.0 kHz, while only the group with the 18 h interval between the toughening and traumatic exposures showed less outer hair cell loss at and above 1.0 kHz. There were no systematic differences in the response of the toughened animals that could be attributed to the 30 day or 18 h post-toughening interval. [Description provided by NIOSH]
• Subjects:
  Animals Ear Hearing Loss Hearing Loss, Noise-Induced Noise Noise, Occupational Occupational Health Safety Sense Organs
• Keywords:
  Animal-studies Author Keywords: Noise-induced Hearing Loss 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 ; Journal Article
• Place as Subject:
  New York ; OSHA Region 2
• CIO:
  National Institute for Occupational Safety and Health (NIOSH) ; National Institute for Occupational Safety and Health (NIOSH)
• Topic:
  Workplace Safety & Health ; Workplace Safety & Health
• Location:
  North America ; North America
• Pages in Document:
  101-110
• Volume:
  129
• Issue:
  1
• NIOSHTIC Number:
  nn:20029980
• Citation:
  Hear Res 1999 Mar; 129(1-2):101-110
• Contact Point Address:
  Auditory Research Laboratory, Plattsburgh State University of New York, 12901-2681
• Email:
  ahroonwa@splava.cc.plattsburgh.edu
• Federal Fiscal Year:
  1999
• 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:c953e6026f199ee7c1cbb37949a1f44b923f917f481755cdcf65b28912b33a58e3784ff22cde865cbf8beca4b57ac7296119d707e00db2bb755d39c696b2f814
• Download URL:
  https://stacks.cdc.gov/view/cdc/190843/cdc_190843_DS1.pdf
• File Type:
  [PDF - 509.62 KB ]