Working memory and short-term memory deficits in ADHD: A bifactor modeling approach.

Area of Science:

• Neuroscience
• Child Psychology
• Cognitive Science

Background:

• Attention-deficit/hyperactivity disorder (ADHD) is frequently associated with working memory impairments.
• Previous research has been limited by methodological and statistical constraints, impacting confidence in findings.
• Distinguishing between central executive working memory and short-term memory deficits in pediatric ADHD requires precise measurement.

Purpose of the Study:

• To precisely characterize the nature and magnitude of working memory deficits in pediatric ADHD.
• To investigate the relationship between ADHD symptom severity and specific memory impairments.
• To differentiate between central executive, phonological short-term, and visuospatial short-term memory deficits in ADHD.

Main Methods:

• Utilized a well-characterized sample of 172 children (ages 8-13) with ADHD.
• Administered multiple, counterbalanced working memory tests.
• Employed bifactor-(s-1) modeling to analyze memory components.

Main Results:

• ADHD was associated with very large impairments in central executive working memory (75%-81% affected).
• These central executive deficits correlated with ADHD symptom severity.
• A smaller impairment was observed in visuospatial short-term memory (38% affected), but it did not correlate with symptom severity; phonological short-term memory remained intact.

Conclusions:

• Pediatric ADHD is characterized by significant central executive working memory deficits that align with behavioral symptoms.
• Visuospatial short-term memory deficits in ADHD may be epiphenomenal.
• Phonological short-term memory appears to be intact in children with ADHD.