Christiansen, H. & Oades, R. D.

Negative priming within a Stroop task in children and adolescents with attention-deficit/hyperactivity disorder (ADHD), their siblings and independent controls.. Journal of Attention Disorders, 13, 497-504.doi:10.1177/1087054708325974. [Request a copy] - View Article

Introduction: Negative-priming (NP) is the slowed response to a stimulus now a target - that was previously ignored as a non-target.

Methods: We compared response times (RT) in NP task conditions that provide one sort of interference in stimulus processing with the more classic "interference" provided by congruent/incongruent stimuli in a Stroop condition** in the same task in children diagnosed with ADHD their unaffected siblings & independent Cs. [** e.g. Name the print colour of word denoting another colour]

Speed, accuracy & variability of responses were compared on a computerized NP - Stroop test for 35 children with ADHD, 24 siblings without the diagnosis and 37 independent healthy control youngsters (6-17 years of age).

Results:
1 - NP was evident at test-onset for congruent trials in children without a diagnosis, & was reduced initially in those with ADHD.

2 - This occurred in the absence of a significant between-group difference of the Stroop-interference effect, --- & --- independently of age or symptom severity.

3 - NP effects were masked by those arising from incongruency.

4 - ADHD cases showed more intra-individual response-time variability.

Discussion:

a) Both NP in normal children & its reduction in ADHD cases attenuated across trials reflecting the increased facilitation from previous stimulation.

b) We show differences between the nature of the interference caused by different conditions of stimulus presentation (e.g., NP measures in congruent and incongruent presentations showed positive and negative correlations with Stroop interference, respectively)

Support from NIH and Janssen-Cilag