Yes, short-term (working) memory issues are a core feature of ADHD
Patients with ADHD consistently demonstrate executive deficits in both visuospatial and verbal working memory, which are well-established neuropsychological impairments associated with the disorder 1.
Understanding the Memory Deficits in ADHD
Working Memory vs. Short-Term Memory
The evidence clearly distinguishes between different types of memory impairments:
Working memory (central executive): This shows very large magnitude impairments in ADHD, with effect sizes of d = 1.63-2.03, meaning 75-81% of pediatric ADHD cases are impaired 2. These deficits directly covary with both inattentive and hyperactive/impulsive symptom severity across parent and teacher reports.
Visuospatial short-term memory: Shows a moderate impairment (d = 0.60; 38% impaired), though this appears to be epiphenomenal rather than a core feature, as it doesn't correlate with ADHD symptom severity 2.
Phonological (verbal) short-term memory: The evidence here is mixed. The most rigorous 2020 study found no evidence linking ADHD with phonological short-term memory deficits 2. However, older studies and clinical samples show that a majority of adolescents and adults with ADHD demonstrate significant discrepancies between verbal IQ and short-term verbal memory performance 3.
Clinical Implications
Working memory deficits are substantiated by abnormal findings in brain imaging studies, particularly in frontostriatal, frontoparietal, and ventral attention networks 1. Functional neuroimaging using fNIRS demonstrates reduced hemodynamic response in the dorsolateral prefrontal cortex during working memory tasks in children with ADHD, but not during short-term memory tasks 4.
Treatment Considerations
Stimulant medications (methylphenidate and amphetamines) improve short-term memory, reaction time, and sustained attention 5. These medications enhance dopamine and norepinephrine pathways crucial for prefrontal cortex function, which ameliorates deficits in inhibitory control and working memory 5.
Common Pitfalls to Avoid
Don't assume all memory types are equally impaired: Central executive working memory is the primary deficit, not necessarily phonological short-term memory.
Recognize the functional impact: These memory impairments contribute to reduced academic achievement, employment difficulties, and overall psychosocial functioning 1. Untreated ADHD negatively affects long-term outcomes including educational attainment and occupational success.
Consider comorbidities: Memory performance in ADHD is not significantly associated with depression symptom severity, but is positively associated with IQ 6.
Bottom Line for Clinical Practice
When evaluating patients with ADHD, expect working memory deficits to be present in the majority of cases. These deficits are not just correlational—they represent a core neurobiological feature of the disorder affecting frontal-striatal networks. Assessment should include evaluation of visuospatial and verbal working memory domains, as these impairments directly impact daily functioning and treatment planning. Stimulant medications remain first-line treatment and demonstrably improve these memory deficits 5, 1.