Working memory and everyday cognition in adults with Down's syndrome

Area of Science:

• Cognitive Psychology
• Neuroscience
• Developmental Disabilities

Background:

• Previous research suggests working memory deficits in Down's syndrome (DS), with debates on whether it affects the phonological loop or central executive.
• Some studies propose similarities in working memory functioning between individuals with DS and those with Alzheimer's disease.

Purpose of the Study:

• To investigate the specific working memory components affected in middle-aged individuals with Down's syndrome.
• To compare working memory functioning and everyday cognition skills between individuals with DS and those with other intellectual disabilities.

Main Methods:

• Matched comparison of 15 middle-aged individuals with DS and 15 individuals with intellectual disability of mixed etiology based on non-verbal intelligence.
• Administration of a diverse set of tasks to assess phonological loop, central executive, and overall working memory functioning.
• Assessment of everyday cognition skills in both groups.

Main Results:

• Individuals with DS demonstrated significantly poorer performance on all tasks measuring the phonological loop.
• No significant differences were found between the groups in tasks assessing other working memory components or overall everyday cognition skills.
• The phonological loop deficit in DS did not appear to affect vocabulary or other daily cognitive abilities.

Conclusions:

• The findings strongly support a specific deficit in the phonological loop component of working memory in individuals with Down's syndrome.
• There is no evidence for a specific deficit in the central executive component of working memory in this population.
• The identified phonological loop impairment in DS does not seem to generalize to deficits in vocabulary or broader everyday cognition skills.