The relationship between prospective memory, working memory and self-rated memory performance in individuals with intellectual disability

In the present study, prospective memory, working memory and self-rated memory performance were assessed in five individuals with intellectual disability and 10 individuals without intellectual disability. Prospective memory was taxed by means of a video-based procedure and a more naturalistic task, working memory was taxed by means of digit and picture span tasks, and a questionnaire was used to measure self-rated prospective and retrospective memory. The spread of performance was wide on prospective memory and working memory tasks, foremost for individuals with intellectual disability. Self-rated memory did not differ between the two groups, although there were large differences in memory performance on the other memory tasks. The results are interpreted in terms of how limitations in working memory contribute to prospective memory failures among individuals with intellectual disability. To remember ‘when to’ perform a prospective memory task seems to be more difficult to master than remembering ‘what to do’ for individuals with intellectual disability.