How does ADHD affect working memory and attention?
ADHD is fundamentally a disorder of executive function, and working memory is the most important executive function. The central executive — the part of working memory that directs attention and filters distractions — is consistently underactive in ADHD, particularly in the right prefrontal cortex.
| Metric | Neurotypical average | ADHD typical range |
|---|---|---|
| Forward digit span | 7 digits | 5–6 digits |
| Backward digit span | 5 digits | 3–4 digits |
| CPT hit rate | 88–95% | 70–80% |
| CPT commission error rate | 2–5% | 8–15% |
| Reaction time variability | Low (consistent) | High (inconsistent) |
| Sustained attention over time | Stable | Typically degrades |
The Number Memory test measures forward digit span and is sensitive to working memory deficits. The Attention test measures CPT-style sustained attention. Together they provide a useful (though not diagnostic) picture of ADHD-related cognitive patterns.
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Based on the clinical CPT — free, no account needed.
Quick Answer
ADHD is strongly associated with deficits in the central executive component of working memory — the system that filters distractions and manages information in mind. People with ADHD typically score 1–2 standard deviations below average on digit span and sustained attention tasks.
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