Post-Error Slowing in Patients With ADHD: A Meta-Analysis.

OBJECTIVE

Post-error slowing (PES) is a cognitive mechanism for adaptive responses to reduce the probability of error in subsequent trials after error. To date, no meta-analytic summary of individual studies has been conducted to assess whether ADHD patients differ from controls in PES.

METHOD

We identified 15 relevant publications, reporting 26 pairs of comparisons (ADHD, n = 1,053; healthy control, n = 614). Random-effect meta-analysis was used to determine the statistical effect size (ES) for PES.

RESULTS

PES was diminished in the ADHD group as compared with controls, with an ES in the medium range (Cohen's d = 0.42). Significant group difference was observed in relation to the inter-stimulus interval (ISI): While healthy participants slowed down after an error during long (3,500 ms) compared with short ISIs (1,500 ms), ADHD participants sustained or even increased their speed.

CONCLUSION

The pronounced group difference suggests that PES may be considered as a behavioral indicator for differentiating ADHD patients from healthy participants.