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Nonorganic Hearing Loss. SPA 4302 Summer 2006. Some Terminology. Pseudohypacusis – False hearing loss Functional – Loss with no organic disorder detected. Psychogenic – Loss/disorder arising from psychological conditions, older synonym was hysterical deafness
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Nonorganic Hearing Loss SPA 4302 Summer 2006
Some Terminology • Pseudohypacusis – False hearing loss • Functional – Loss with no organic disorder detected. • Psychogenic – Loss/disorder arising from psychological conditions, • older synonym was hysterical deafness • Nonorganic – Apparent loss with no known disorder or insufficient evidence to explain it • Malingering – deliberately faking a loss
Patients with Nonorganic Hearing Loss • Adults seeking financial or other gain (predominantly male) • Children seeking attention or ? • Persons with psychological disorders • conversion neurosis
What are the first signs? • Disagreement: • among test results • SRT vs PTA • Audiometric vs AR thresholds, etc) • between test results and behavior • Lack of Crossover • no shadow curve in the unmasked results • Odd results • Repeating half of the spondees?
Tests for Nonorganic Hearing Loss • The Stenger – for unilateral HL • Delayed Auditory Feedback Tests • Tone Tap Test • Delayed Speech Test • Varying Intensity Story Test • Objective tests (AR, AEPs, OAEs)-
The Stenger • Based on the “Stenger Phenomenon” When a listener is presented with the same type of sound in both ears, s/he will only hear a single sound and hear it in the ear in which it is louder. • 2 tones: • At + 10 dB SL in good ear • At – 10 dB SL in “bad” ear • If no response: you’ve caught them! --why? • Part II: reduce level in “bad” ear until they respond: “minimum contralateral interference level” --an estimate of the true threshold.
Stenger Example at 1000 Hz RE STIMULUS INITIAL LE STIMULUS
Delayed Auditory Feedback Tests • Delayed speech test: Have pt talk while you play back their own voice to them with a 200 ms delay. Gradually raise level: when they hear their own voice, they will change their speech (intensity, rate, fluency) • Pure tone DAF (Tone Tap Test): Have pt tap out a rhythm on a pressure transducer. Each tap will generate a tone. Gradually raise level of tone: when they hear the delayed tones, they will change their pattern of tapping.
Varying Intensity Story Test • Patient is asked to listen to a story in one ear, parts are presented above the threshold and some parts are presented below the threshold • The story is presented so rapidly that it is difficult for listeners to distinguish what they can admit to have heard and what they should not • The listener is then asked questions about the story • The topic of discussion changes based on whether or not they could hear the parts of the story presented below their threshold • Information on china (dishes) is presented above threshold • Information on China (the country) is presented below the threshold and fits into the other story line, thus changing the story topic if the patient is faking a hearing loss
Objective tests (AR, AEPs, OAEs) • AR Өs at extremely low SL’s • e.g., pure tone Ө of 60 & AR Ө of 80. • SPAR: calculating audiogram from AR Өs • AEP’s : objective Ө estimation • Tests we’ve already discussed • Auditory Steady State Responses (ASSRs) • OAEs: measures of cochlear health • Valuable in noise exposure cases in particular
Management of Patients with Nonorganic Hearing Loss • Once you have identified the problem: • let them know you know • shift blame onto your shoulders • If they don’t come ‘round?... • don’t report audiometric thresholds if you don’t believe them • In your report, be careful about the terms you choose.