RESUMO
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.
Assuntos
Afasia/diagnóstico , Audiometria da Fala/métodos , Percepção da Fala/fisiologia , Teste do Limiar de Recepção da Fala/métodos , Adulto , Análise de Variância , Audiometria de Tons Puros , Lesões Encefálicas/diagnóstico , Estudos de Coortes , Feminino , Perda Auditiva/diagnóstico , Humanos , Masculino , Pessoa de Meia-Idade , Mascaramento Perceptivo/fisiologia , Valores de Referência , Testes de Discriminação da Fala/métodosRESUMO
OBJECTIVES: Individuals with phenylketonuria (PKU) can exhibit deficits in executive functions, intelligence, attention, visual-spatial processing abilities, and efficiency stemming presumably from deficient neurotransmitter synthesis, even when the disorder is diagnosed and treated early. Basic audiological and electrophysiological evaluations were used to examine the peripheral and central auditory pathways of children with early-treated PKU, who followed adequate versus inadequate diets. Results were compared with those of age-matched children without PKU. DESIGN: The control group included 35 children aged 5 to 16 years, and the experimental group included 25 children with classic PKU, all of whom were diagnosed and treated early. The experimental group comprised children of two subgroups, divided according to their dietary control, as follows: 8 children aged 6 to 13 years with adequate diets (group A); 17 children ages 6 to 15 years demonstrating inadequate diets (group B). All participants underwent auditory evaluations, including otoscopy, pure-tone and speech audiometry, immittance testing (tympanometry and assessment of contralateral stapedial reflex thresholds), and evaluations of auditory brainstem and middle latency responses. The demographic variables and audiological examination results were analyzed for all groups. Results among groups and subgroups were compared using analysis of variance with repeated measures to test statistical significance across factors and measures at the p = 0.05 level. RESULTS: Audiometric evaluation revealed results within normal limits for all groups, except for one child from the inadequate diet group, who showed a mild bilateral conductive hearing loss. Results of speech and immittance audiometry suggested the children in group B as having poorer average speech-discrimination scores and higher stapedial reflex thresholds at 4000 Hz. Auditory brainstem response results revealed longer average latencies for waves III and V and greater interaural differences for wave V in group B, although both groups A and B showed longer average latencies for the interpeak interval I-V, compared with the control group. Middle latency responses showed no significant differences in the latencies of the Na and Pa waves or the Na-Pa amplitude for the experimental group, but electrode or ear effects were present in 87.5% of group A and 58.8% of group B. CONCLUSIONS: Overall, differences observed tended to be small (by clinical diagnostic standards), yet suggest that children with PKU exhibit some effect of this disorder on the pontine auditory pathway, even when diagnosed/treated early and independent of the appropriateness of diet. It thus seems prudent to follow PKU children with auditory processing assessments to evaluate functional implications of these findings.