| Article ID | Journal | Published Year | Pages | File Type |
|---|---|---|---|---|
| 3042998 | Clinical Neurophysiology | 2015 | 10 Pages |
•Frontal EEG alpha asymmetry was examined in adult ADHD patients on two measurement occasions, separated by two weeks.•An alpha asymmetry pattern reflecting elevated approach motivation was associated with pronounced ADHD symptoms and alpha asymmetry displayed sufficient test–retest reliability.•Results support a motivational dysfunction hypothesis of adult ADHD.
ObjectiveAttention-deficit/hyperactivity disorder (ADHD) involves motivational dysfunction, characterized by excessive behavioral approach tendencies. Frontal brain asymmetry in the alpha band (8–13 Hz) in resting-state electroencephalogram (EEG) represents a neural correlate of global motivational tendencies, and abnormal asymmetry, indicating elevated approach motivation, was observed in pediatric and adult patients. To date, the relation between ADHD symptoms, depression and alpha asymmetry, its temporal metric properties and putative gender-specificity remain to be explored.MethodsAdult ADHD patients (n = 52) participated in two resting-state EEG recordings, two weeks apart. Asymmetry measures were aggregated across recordings to increase trait specificity. Putative region-specific associations between asymmetry, ADHD symptoms and depression, its gender-specificity and test–retest reliability were examined.ResultsADHD symptoms were associated with approach-related asymmetry (stronger relative right-frontal alpha power). Approach-related asymmetry was pronounced in females, and also associated with depression. The latter association was mediated by ADHD symptoms. Test–retest reliability was sufficient.ConclusionsThe association between reliably assessable alpha asymmetry and ADHD symptoms supports the motivational dysfunction hypothesis. ADHD symptoms mediating an atypical association between asymmetry and depression may be attributed to depression arising secondary to ADHD. Gender-specific findings require replication.SignificanceFrontal alpha asymmetry may represent a new reliable marker of ADHD symptoms.
