Aims: The Computerized Revised Token Test (CRTT) is a standardized assessment of language comprehension and processing abilities. The CRTT-Reading-Word-Fade (CRTT-R-WF) is a self-paced version of the CRTT in which the previous word in a sentence disappears with the onset of each new word. In addition to the language skills needed to complete the assessment, the CRTT also requires perceptual-motor and cognitive capabilities that have the potential to negatively influence participant results. The purpose of this study was to investigate the effect of age and hand preference as two of these potential influences on CRTT performance.
Methods: Sixty-four healthy, normal adults participated in this study. Participants were divided into two groups: younger adults (Group 1, 20-32 years) and older adults (Group 2, 65-78 years). Each group consisted of 32 participants (16 males and 16 females). All 64 participants completed the CRTT-R-WF version of the CRTT and CRTT-RT battery with both their right and left hand. The CRTT-R-WF mean scores, efficiency scores, and reading times were investigated to evaluate the effects of age and hand preference on the accuracy and efficiency of participant responses.
Results: Statistically significant main effects were observed for both age and hand use on CRTT-R-WF mean scores, efficiency scores, and reading plus response times. The older adults demonstrated significantly lower mean and efficiency scores, as well as significantly slower reading times. Mean scores, efficiency scores and reading plus response times achieved with the left hand were also significantly lower and slower than the right hand across participants. Significant interactions between age and hand were found on CRTT-R-WF mean and efficiency scores. The older adult’s mean and efficiency scores were over-additively reduced with their left hand.
Discussion: Decreased comprehension and efficiency of responses, as measured by the CRTT-R-WF, were observed with age and with non-preferred hand use with a computer mouse. Slower reading plus response times were also observed as an effect of age. Theories of working memory, processing speed, and resource allocation were discussed as possible explanations as to why these results were observed
