SEQUENCING DEFICITS IN SUBJECTS WITH DEVELOPMENTAL DYSPRAXIA AND ADULT-ONSET APRAXIA

Objective: The purpose of this study was to examine and compare the pe rformance of children with developmental dyspraxia and adults with apr axia to learn and retain two sequencing tasks. Study design: Three gro ups of subjects with dyspraxia and apraxia (children and young adults with both dyspraxia and learning disabilities and older adults with ap raxia and left hemisphere strokes) and three groups of age-matched con trol subjects learned one-handed shoe tying and a hand sequence task. Retention was assessed after a 5-min delay. Performance was scored as the number of trials needed to perform each task and the types of erro rs that were made. Results: For both the tasks, the control groups per formed better than the groups with dyspraxia/apraxia and performance d uring the retention trials was better than performance during the lear ning trials. On the hand sequence task, the children and young adult g roups performed better than the older adult groups. Conclusions: Subje cts with dyspraxia and apraxia have difficulty with similar sequencing tasks. However, the poorer performance by the older adult group with apraxia suggests that the underlying mechanisms for sequencing may be different for apraxia than for dyspraxia. (C) 1998 Elsevier Science Ir eland Ltd.