How does the Continuous Performance Test detect attention problems?
The short answer
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.
The data
| 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 |
What it means for you
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.
Medical disclaimer
This content is for educational purposes only and is not medical advice. Scores from online tests are not diagnostic - if you are concerned about symptoms such as memory loss, attention problems, or cognitive decline, consult a qualified clinician.
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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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