Reaction time as a correlate of intellectual ability for the learning-disabled

This study investigated the relative performance of learning disabled and control schoolchildren on reaction time measures. Both the mean reaction time (RT), movement time (MT), and intra-individual variability (intra-SD) and the correlation of these measures to IQ were compared to evaluate the potential value of chronometric measures for the assessment of learning disabilities. Thirty learning disabled students were selected from the Resource Specialist Programs of four participating elementary schools. Thirty control subjects were matched by age, sex, ethnicity, and cognitive ability. Subject\u27s RT and MT were measured with the use of a Hick Apparatus. Reaction time measures were correlated with IQ scores from the Wechsler Intelligence Scale for Children-Revised (WISC-R). The mean RTs, MTs, and intra-SDs were not significantly different for the learning disabled and control children. The control group displayed a pattern of RT-IQ correlations that conformed to findings from research with other populations. While the relationship of RT and IQ for the learning disabled group did not significantly differ from that for the control group for this small sample, a trend toward a unique pattern of correlations was evidenced. The implications of this pattern and theoretical explanations for its origin are presented. The trends toward a modest differential RT performance for Hispanic subjects are also presented and discussed. Findings suggest that learning disabled children are not deficient in speed of information processing. A unique relationship between RT and IQ may, however, be characteristic of the learning disabled. The potential utility of RT measurement in the assessment of learning disabilities was supported