Title

Anterior cingulate cortex dysfunction in attention-deficit/hyperactivity disorder revealed by fMRI and the Counting Stroop

UMMS Affiliation

Department of Psychiatry

Date

6-22-1999

Document Type

Article

Medical Subject Headings

Adolescent; Adult; Attention Deficit Disorder with Hyperactivity; Cerebral Cortex; Cognition Disorders; Female; Gyrus Cinguli; Humans; Magnetic Resonance Imaging; Male; Middle Aged; *Neuropsychological Tests; Reaction Time; Severity of Illness Index

Disciplines

Psychiatry

Abstract

BACKGROUND: The anterior cingulate cognitive division (ACcd) plays a central role in attentional processing by: 1) modulating stimulus selection (i.e., focusing attention) and/or 2) mediating response selection. We hypothesized that ACcd dysfunction might therefore contribute to producing core features of attention-deficit/hyperactivity disorder (ADHD), namely inattention and impulsivity. ADHD subjects have indeed shown performance deficits on the Color Stroop, an attentional/cognitive interference task known to recruit the ACcd. Recently, the Counting Stroop, a Stroop-variant specialized for functional magnetic resonance imaging (fMRI), produced ACcd activation in healthy adults. In the present fMRI study, the Counting Stroop was used to examine the functional integrity of the ACcd in ADHD.

METHODS: Sixteen unmedicated adults from two groups (8 with ADHD and 8 matched control subjects) performed the Counting Stroop during fMRI.

RESULTS: While both groups showed an interference effect, the ADHD group, in contrast to control subjects, failed to activate the ACcd during the Counting Stroop. Direct comparisons showed ACcd activity was significantly higher in the control group. ADHD subjects did activate a frontostriatal-insular network, indicating ACcd hypoactivity was not caused by globally poor neuronal responsiveness.

CONCLUSIONS: The data support a hypothesized dysfunction of the ACcd in ADHD.

Rights and Permissions

Citation: Biol Psychiatry. 1999 Jun 15;45(12):1542-52.

Related Resources

Link to Article in PubMed

PubMed ID

10376114