The Effect of Sound Stimulation on Pure-tone Hearing Threshold
|The safety and scientific validity of this study is the responsibility of the study sponsor and investigators. Listing a study does not mean it has been evaluated by the U.S. Federal Government. Read our disclaimer for details.|
|ClinicalTrials.gov Identifier: NCT01184248|
Recruitment Status : Completed
First Posted : August 18, 2010
Last Update Posted : September 8, 2011
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.
|Condition or disease||Intervention/treatment||Phase|
|Sensorineural Hearing Loss||Behavioral: Sound stimulation||Not Applicable|
|Study Type :||Interventional (Clinical Trial)|
|Estimated Enrollment :||30 participants|
|Intervention Model:||Single Group Assignment|
|Masking:||None (Open Label)|
|Official Title:||The Effect of Sound Stimulation on Pure-tone Hearing Threshold|
|Study Start Date :||May 2010|
|Actual Primary Completion Date :||December 2010|
|Actual Study Completion Date :||January 2011|
- Behavioral: Sound stimulation
Listening to sound stimuli at the lowest audible level.
- Changes of pure-tone hearing thresholds after sound stimulation [ Time Frame: 4-6 weeks ]
To learn more about this study, you or your doctor may contact the study research staff using the contact information provided by the sponsor.
Please refer to this study by its ClinicalTrials.gov identifier (NCT number): NCT01184248
|United States, California|
|Los Angeles, California, United States, 90005|
|Principal Investigator:||Eunyee Kwak, Ph.D.||Earlogic Auditory Research Institute|