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PURPOSE: Hearing loss simulation (HLS) has been recommended for clinical teaching and counseling of patients and their families, so that they can experience hearing impairment. However, few validated procedures for simulating hearing loss are available to instructors and practicing clinicians. The aim of this study was to assess the accuracy of the Immersive Hearing Loss and Prosthesis Simulator (I-HeLPS) on reducing hearing sensitivity and word recognition to determine its adequacy for educational and clinical use. METHOD: Thirty-seven young adults with normal hearing completed hearing threshold and word recognition testing under normal and simulated hearing losses. The accuracy of the nominal hearing threshold settings within the I-HeLPS software was assessed with behavioral detection of frequency-modulated pure tones presented in a calibrated sound field, while listeners wore I-HeLPS headphones. The impact of the HLSs on speech perception was measured using the California Consonant Test. Hearing thresholds, word identification accuracy, and sound confusions were compared across listening conditions. RESULTS: Hearing thresholds increased systematically with worse simulated hearing loss. Performance on the California Consonant Test worsened, and the number of phoneme confusions increased with simulated hearing loss severity. Most of the confusions were place confusions with near neighbors and manner confusions increased as a function of increasing severity of simulated hearing loss. CONCLUSIONS: The I-HeLPS accurately elevated hearing thresholds with increasing HLS severity and impacted word recognition in a manner consistent with sensorineural hearing loss. The simulations were considered reasonable for educational and clinical purposes. SUPPLEMENTAL MATERIAL: https://doi.org/10.23641/asha.24520966.
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Purpose During videofluoroscopic examination of swallowing, patients commonly are instructed to hold a bolus in their mouth until they hear a verbal instruction to swallow, which usually consists of the word swallow and is commonly referred to as the command swallow condition. The language-induced motor facilitation theory suggests that linguistic processes associated with the verbal command to swallow should facilitate the voluntary component of swallowing. As such, the purpose of the study was to examine the linguistic influences of the verbal command on swallowing. Method Twenty healthy young adult participants held a 5-ml liquid bolus in their mouth and swallowed the bolus after hearing one of five acoustic stimuli presented randomly: congruent action word (swallow), incongruent action word (cough), congruent pseudoword (spallow), incongruent pseudoword (pough), and nonverbal stimulus (1000-Hz pure tone). Suprahyoid muscle activity during swallowing was measured via surface electromyography (sEMG). Results The onset and peak sEMG latencies following the congruent action word swallow were shorter than latencies following the pure tone and pseudowords but were not different from the incongruent action word. The lack of difference between swallow and cough did not negate the positive impact of real words on timing. In contrast to expectations, sEMG activity duration and rise time were longer following the word swallow than the pure tone and pseudowords but were not different from cough. No differences were observed for peak suprahyoid muscle activity amplitude and fall times. Conclusions Language facilitation was observed in swallowing. The clinical utility of the information obtained in the study may depend on the purposes for using the command swallow and the type of patient being assessed. However, linguistic processing under the command swallow condition may alter swallow behaviors and suggests that linguistic inducement could be useful as a compensatory technique for patients with difficulty initiating oropharyngeal swallows.
Assuntos
Deglutição , Idioma , Eletromiografia , Voluntários Saudáveis , Humanos , Boca , Adulto JovemRESUMO
PURPOSE: The purpose of this study was to evaluate the ability of persons with aphasia, with and without hearing loss, to complete a commonly used open-set word recognition test that requires a verbal response. Furthermore, phonotactic probabilities and neighborhood densities of word recognition errors were assessed to explore potential underlying linguistic complexities that might differentially influence performance among groups. METHOD: Four groups of adult participants were tested: participants with no brain injury with normal hearing, participants with no brain injury with hearing loss, participants with brain injury with aphasia and normal hearing, and participants with brain injury with aphasia and hearing loss. The Northwestern University Auditory Test No. 6 (NU-6; Tillman & Carhart, 1966) was administered. Those participants who were unable to respond orally (repeating words as heard) were assessed with the Picture Identification Task (Wilson & Antablin, 1980), permitting a picture-pointing response instead. Error patterns from the NU-6 were assessed to determine whether phonotactic probability influenced performance. RESULTS: All participants with no brain injury and 72.7% of the participants with aphasia (24 out of 33) completed the NU-6. Furthermore, all participants who were unable to complete the NU-6 were able to complete the Picture Identification Task. There were significant group differences on NU-6 performance. The 2 groups with normal hearing had significantly higher scores than the 2 groups with hearing loss, but the 2 groups with normal hearing and the 2 groups with hearing loss did not differ from one another, implying that their performance was largely determined by hearing loss rather than by brain injury or aphasia. The neighborhood density, but not phonotactic probabilities, of the participants' errors differed across groups with and without aphasia. CONCLUSIONS: Because the vast majority of the participants with aphasia examined could be tested readily using an instrument such as the NU-6, clinicians should not be reticent to use this test if patients are able to repeat single words, but routine use of alternative tests is encouraged for populations of people with brain injuries.