VERBAL SHORT-TERM-MEMORY SPAN IN SPEECH-DISORDERED CHILDREN - IMPLICATIONS FOR ARTICULATORY CODING IN SHORT-TERM-MEMORY

One influential explanation of the development of verbal short‐term memory in children argues that short‐term memory capacity is a direct function of speech rate. This theory predicts that children with pathologically slow speech will show reduced verbal short‐term memory capacity and will show less evidence of speechbase coding on verbal memory task. To test this prediction, verbal short‐term memory span was assessed using a task that did not require a verbal response in 37 speech‐disordered children and 37 age‐ and sex‐matched controls (age range 4–15 years). The speech‐disordered group had a significantly lower short‐term memory capacity, a smaller word length effect, and reduced speech‐motor activity during rehearsal periods. Covariance analyses revealed that these differences were not a function of general intellectual or motor speed differences between the groups, and that speech rate as a covariate abolished group differences in short‐term memory. These results suggest that speech rate may be a causal determinant of verbal short‐term memory capacity. Copyright © 1991, Wiley Blackwell. All rights reserved