Title: The Computerized Revised Token Test: Assessing the Impact of Age and Sound Intensity
Authors: Sheila Pratt, Ph.D.
Cynthia Eberwein, MS
Malcolm McNeil, Ph.D.
Amanda Ortmann, M.A.
Jillyn Roxberg, M.A.
Tepanta Fossett, M.A.
Neil Szuminsky, M.S.
John Durrant, Ph.D.
Patrick Doyle, Ph.D.
Affiliations:Veteran’s Administration Pittsburgh Healthcare System
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University of Pittsburgh
Department of Communication Science & Disorders
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Title: The Computerized Revised Token Test: Assessing the Impact of Age and Sound Intensity
Abstract:
Background
The Revised Token Test (McNeil & Prescott, 1978, RTT) is a well-established test of auditory language processing disorders in persons with aphasia. A computerized version of the test, the Computerized Revised Token Test (C-RTT), was developed recently in our laboratory to better control stimuli presentation, and eliminate variability associated with the complex scoring requirements of the RTT.
In the current study the impact of participant age and acoustic signal intensity on performance of non-brain injured adults on the C-RTT was assessed. Although age effects have not observed with the RTT, we believed that strict adherence to timing and stimuli characteristics allowed by computer administration and scoring could separate young from older adults.
Methods
The participants consisted of Young and Elder adults without history or evidence of speech-language impairment or brain injury. The Young adults were undergraduate students (20-29 years) and the Elder group (70-85 years) consisted of community dwelling adults. The Young participants had normal hearing and speech perception skills, while the hearing of the Elder participants ranged from moderate to severely impaired. The speech perception skills of the Elder participants were consistent with their age and hearing loss severity. In order to eliminate auditory deprivation as a factor they all were previous hearing aid users.
A fifty-item version of the C-RTT was administered to all of the participants in soundfield at a range of intensity levels, such that performance-intensity functions could be plotted. The overall and subtest responses were scored automatically and online. The Elders were administered the C-RTT with and without their hearing aids. The level at which maximum performance occurred for each performance-intensity function was determined.
Results
The intensity levels at which the Elder participants performed maximally were significantly greater than the Young adults regardless of whether the Elders were wearing their hearing aids. The differences between the mean presentation levels were 37 dB SPL without hearing aids and 23 dB SPL with hearing aids. The maximum overall scores of the Elder participants were not different from the Young participants regardless of hearing aid use. However, at the subtest level the older participants demonstrated consistently worse performance than the Young participants on Subtest 8. When presentation level was adjusted as a covariate, the groups were significantly different and a greater number of subtests differences between the groups became evident. The Elders differed from the Young participants on Subtests 6 and 8 regardless of hearing aid use. Although performance was somewhat more depressed when they wore their hearing aids than when they did not there were no significant differences per hearing aid use.
Discussion
The results are consistent with previous work in hearing and aging, indicating that audibility plays a substantive role in auditory processing of language in older adults (Humes & Floyd, 2005; Humes & Roberts, 1990). Once speech signals are sufficiently intense older adults tend to process speech and language similarly to younger adults, although increasing linguistic, memorial and acoustic demands will differentiate the groups as was observed with Subtest 8.
Conclusion
The results have implications for administration and interpretation of the C-RTT and other tests of language processing.
References
McNeil, M.R. & Prescott, T.E. (1978). Revised Token Test. Austin, TX: Pro-ed.
Humes, L.E. & Floyd, S.S. (2005). Measures of working memory, sequence learning, and speech recognition in the elderly. Journal of Speech, Language, and Hearing Research, 48, 224-235.
Humes, L.E. & Roberts, L. (1990). Speech-recognition difficulties of the hearing-impaired elderly: The contributions of audibility. Journal of Speech and Hearing Research, 33, 726-735.