Effects of short-term exposure to sound at very high and ultrasonic frequencies at subthreshold levels; a double-blind provocation study.

Not Applicable

Completed

• Conditions: Nausea; Anxiety; Pain or sensation of pressure in the ears; Tinnitus; Dizziness or light-headedness; Headache or pain or pressure other than in the ears; Inability to concentrate; Ear - Other ear disorders

• Registration Number: ACTRN12616001410448
• Lead Sponsor: niversity of Southampton

Brief Summary

Not available

Detailed Description

Not available

Study Timeline

• Results First Posted: 1900-01-01
• Study Start: 2016-10-10
• Last Update Posted: 13 January 2020

Recruitment & Eligibility

• Status: Completed
• Sex: All
• Target Recruitment: 32

Inclusion Criteria

For participants deemed sensitive or symptomatic, the participant must have reported adverse reactions which they attribute to ultrasound exposure in the past.
For aysmptomatic participants, they must have hearing within normal limits at conventional audiometric frequencies (0,25 - 8 kHz).

Exclusion Criteria

1. Severe tinnitus as identified by screening questionnaire
2. Abnormality detected on otoscopy, such as discharge, inflammation, infection, or excessive wax.
3. Contraindications in screening questionnaire such as recent ear infection, current ear pain, or exposure to very loud sounds in the last 24-hours.
4. Excessive intake of caffine in the two hours before the study (e.g. 2 cups of strong coffee)
5. Excessive intake of alcholol withing 24 hours of the study (e.g. more than 2 pints of beer, or two glasses of wine)
6. Colour blindness effecting participants ability to distinguish red, green and blue (which could affect outcomes on the sustained attention task used)
7. Epilepsy (which might be agrivated by the sustained attention task, which has flashing images)
8. Use of recreational drugs in the last week.
9. Strenuous physical or mental activity on the day of the experiment.
10 Hyperacusis experienced for sounds at conventional frequencies (< 10 kHz).

Study & Design

• Study Type: Interventional
• Study Design: Not specified

Primary Outcome Measures

Name	Time	Method
The primary outcome measure will be a composite obtained by summing the scores on a 7-item subjective rating scale. The seven items are tinnitus, pain or fullness in the ear, Headache or pain or pressure somewhere other than my ears, nausea, dizziness or light headedness, anxiety, and inability to concentrate. For each item, the participant will be asked to rate the severity of their symptoms on an 11-point scale running from 0” (No symptoms) to 10” Extreme severity. The scale is administered via computer and does not allow fractional selections.[Immediately following each exposure condition (i.e. true or sham exposure)]