NCT01184248

Brief Summary

The purpose of this study is to investigate if sound stimulation could improve pure-tone hearing threshold. In the late 1990s, researchers discovered that acoustic stimuli slow progressive sensorineural hearing loss and exposure to a moderately augmented acoustic environment can delay the loss of auditory function. In addition, prolonged exposure to an augmented acoustic environment could improve age-related auditory changes. These ameliorative effects were shown in several types of mouse strains, as long as the acoustic environment was provided prior to the occurrence of severe hearing loss. In addition to delaying progressive hearing loss, acoustic stimuli could also protect hearing ability against damage by traumatic noise. In particular, a method called forward sound conditioning (i.e., prior exposure to moderate levels of sound) has been shown to reduce noise-induced hearing impairment in a number of mammalian species, including humans. Interestingly, recent report has suggested that low-level sound conditioning also reduces free radical-induced damage to hair cells, increases antioxidant enzyme activity, and reduces Cox-2 expression in cochlea, and can enhance cochlear sensitivity. Specifically, increased cochlear sensitivity was observed when distortion product otoacoustic emissions (DPOAEs) and compound action potentials (CAPs) were measured. In addition to forward sound conditioning, backward sound conditioning (i.e., the use of acoustic stimuli after exposure to a traumatic noise) has been shown to protect hearing ability against acoustic trauma and to prevent the cortical map reorganization induced by traumatic noise. Based on the results of animal studies, the investigators conducted a human study in 2007 and observed that sound stimulation could improve hearing ability. On average, the pure-tone hearing threshold decreased by 8.91 dB after sound stimulation for 2 weeks. In that study, however, the investigators observed only the hearing threshold changes by sound stimulation. To verify the previous ameliorative effect of sound stimulation, the investigators included a control period in this study.

Trial Health

87
On Track

Trial Health Score

Automated assessment based on enrollment pace, timeline, and geographic reach

Enrollment
30

participants targeted

Target at below P25 for not_applicable

Timeline
Completed

Started May 2010

Shorter than P25 for not_applicable

Geographic Reach
1 country

1 active site

Status
completed

Health score is calculated from publicly available data and should be used for screening purposes only.

Trial Relationships

Click on a node to explore related trials.

Study Timeline

Key milestones and dates

Study Start

First participant enrolled

May 1, 2010

Completed
4 months until next milestone

First Submitted

Initial submission to the registry

August 16, 2010

Completed
2 days until next milestone

First Posted

Study publicly available on registry

August 18, 2010

Completed
4 months until next milestone

Primary Completion

Last participant's last visit for primary outcome

December 1, 2010

Completed
1 month until next milestone

Study Completion

Last participant's last visit for all outcomes

January 1, 2011

Completed
Last Updated

September 8, 2011

Status Verified

September 1, 2011

Enrollment Period

7 months

First QC Date

August 16, 2010

Last Update Submit

September 7, 2011

Conditions

Outcome Measures

Primary Outcomes (1)

  • Changes of pure-tone hearing thresholds after sound stimulation

    4-6 weeks

Interventions

Listening to sound stimuli at the lowest audible level.

Eligibility Criteria

Age18 Years - 70 Years
Sexall
Healthy VolunteersNo
Age GroupsAdult (18-64), Older Adult (65+)

You may qualify if:

  • You are a male or female aged between 18 and 70 years
  • You have 25\~70 dB HL hearing loss at any frequency above 1.5 kHz
  • You are able to use an mp3 player
  • You are able to read English

You may not qualify if:

  • Under the medications that could cause hearing loss (such as gentamicin, aspirin, ibuprofen, or acetaminophen)
  • Chronic disease that could affect hearing (such as diabetes or high blood pressure)
  • Temporal hearing loss
  • Hearing loss more than 75 dB HL at any frequency
  • Ear infections, chronic middle ear disease or any abnormality of the ear canal or ear drum
  • Hearing aid user
  • Pregnant females

Contact the study team to confirm eligibility.

Sponsors & Collaborators

Study Sites (1)

Earlogic Corporation

Los Angeles, California, 90005, United States

Location

Related Publications (6)

  • Canlon B, Borg E, Flock A. Protection against noise trauma by pre-exposure to a low level acoustic stimulus. Hear Res. 1988 Jul 15;34(2):197-200. doi: 10.1016/0378-5955(88)90107-4.

    PMID: 3170362BACKGROUND
  • Miyakita T, Hellstrom PA, Frimanson E, Axelsson A. Effect of low level acoustic stimulation on temporary threshold shift in young humans. Hear Res. 1992 Jul;60(2):149-55. doi: 10.1016/0378-5955(92)90017-h.

    PMID: 1639725BACKGROUND
  • Harris KC, Bielefeld E, Hu BH, Henderson D. Increased resistance to free radical damage induced by low-level sound conditioning. Hear Res. 2006 Mar;213(1-2):118-29. doi: 10.1016/j.heares.2005.11.012. Epub 2006 Feb 8.

    PMID: 16466871BACKGROUND
  • Kujawa SG, Liberman MC. Long-term sound conditioning enhances cochlear sensitivity. J Neurophysiol. 1999 Aug;82(2):863-73. doi: 10.1152/jn.1999.82.2.863.

    PMID: 10444683BACKGROUND
  • Niu X, Tahera Y, Canlon B. Protection against acoustic trauma by forward and backward sound conditioning. Audiol Neurootol. 2004 Sep-Oct;9(5):265-73. doi: 10.1159/000080226. Epub 2004 Aug 13.

    PMID: 15316199BACKGROUND
  • Norena AJ, Eggermont JJ. Enriched acoustic environment after noise trauma reduces hearing loss and prevents cortical map reorganization. J Neurosci. 2005 Jan 19;25(3):699-705. doi: 10.1523/JNEUROSCI.2226-04.2005.

    PMID: 15659607BACKGROUND

MeSH Terms

Conditions

Hearing Loss, Sensorineural

Condition Hierarchy (Ancestors)

Hearing LossHearing DisordersEar DiseasesOtorhinolaryngologic DiseasesSensation DisordersNeurologic ManifestationsNervous System DiseasesSigns and SymptomsPathological Conditions, Signs and Symptoms

Study Officials

  • Eunyee Kwak, Ph.D.

    Earlogic Auditory Research Institute

    PRINCIPAL INVESTIGATOR

Study Design

Study Type
interventional
Phase
not applicable
Allocation
NON RANDOMIZED
Masking
NONE
Purpose
TREATMENT
Intervention Model
SINGLE GROUP
Sponsor Type
INDUSTRY
Responsible Party
SPONSOR

Study Record Dates

First Submitted

August 16, 2010

First Posted

August 18, 2010

Study Start

May 1, 2010

Primary Completion

December 1, 2010

Study Completion

January 1, 2011

Last Updated

September 8, 2011

Record last verified: 2011-09

Locations