Sequencing deficits in subjects with developmental dyspraxia and adult onset apraxia

The purpose of this study was to examine and compare the performance of children with developmental dyspraxia and adults with apraxia to learn and retain two sequencing tasks.

Three groups of subjects with dyspraxia and apraxia (children and young adults with both dyspraxia and learning disabilities and older adults with apraxia and left hemisphere strokes) and three groups of age-matched control 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 errors that were made.

For both the tasks, the control groups performed better than the groups with dyspraxia/apraxia and performance during the retention trials was better than performance during the learning trials. On the hand sequence task, the children and young adult groups performed better than the older adult groups.

Subjects 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.