How does the Continuous Performance Test detect attention problems?
The Continuous Performance Test (CPT) is a computerised attention test that presents stimuli in rapid succession. The participant must respond to a specific target (e.g., the letter X) and withhold response to all others. The test measures two types of errors that correlate strongly with different aspects of ADHD.
| Error type | What it means | ADHD association |
|---|---|---|
| Omission errors (missed targets) | Failed to respond when should have — mind wandered | Inattentive type ADHD |
| Commission errors (false alarms) | Responded when shouldn't have — impulsive response | Hyperactive/impulsive ADHD |
| Reaction time variability | Inconsistent response speed — attention fluctuating | Both types |
| RT slowing over time | Vigilance decrement — attention fatiguing | Both types |
The Attention & Focus test uses a CPT-X paradigm — press Space for X, not for any other letter. It measures your hit rate and speed consistency. While it is a simplified version of clinical CPTs (which run 20+ minutes), it provides a genuine objective measure of sustained attention you can track over time.
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Based on the clinical CPT — free, no account needed.
Quick Answer
The CPT presents stimuli rapidly and requires a response only to a specific target (e.g., press for X, not for other letters). It measures omission errors (missed targets — inattention) and commission errors (responding to non-targets — impulsivity). Both error types are elevated in ADHD.
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