EEG Activity in Females with Attention-Deficit/Hyperactivity Disorder

DSM-5 Adult Attention-Deficit/Hyperactivity Disorder: Sex Differences in EEG Activity

This study examined sex differences in the EEG of adults diagnosed with Attention-Deficit/Hyperactivity Disorder (AD/HD) according to DSM-5 criteria. Sixteen females and 16 males with AD/HD, and age- and sex-matched control groups, had an eyes-closed resting EEG recorded from 19 electrode sites. EEGs were Fast Fourier transformed and estimates for total power, absolute and relative power in the delta, theta, alpha, beta and gamma bands, and the theta/beta ratio, were analysed across nine cortical regions. Males with AD/HD, compared with male controls, had globally reduced absolute beta, globally elevated relative theta, and a larger theta/beta ratio. In contrast, no global effects emerged between females with and without AD/HD. Significant group interactions indicated that globally elevated relative theta and elevated frontal-midline theta/beta ratio noted in males with AD/HD differed significantly from results in females. There are statistically significant EEG differences in relative theta and the theta/beta ratio between males and females with and without AD/HD. These results indicate that AD/HD affects the EEG activity of males and females differently. This study helps confirm the need for further independent examination of AD/HD within female populations.

EEG spectral power, but not theta/beta ratio, is a neuromarker for adult ADHD

Adults with attention-deficit/hyperactivity disorder (ADHD) have been described as having altered resting-state electroencephalographic (EEG) spectral power and theta/beta ratio (TBR). However, a recent review (Pulini et al. 2018) identified methodological errors in neuroimaging, including EEG, ADHD classification studies. Therefore, the specific EEG neuromarkers of adult ADHD remain to be identified, as do the EEG characteristics that mediate between genes and behaviour (mediational endophenotypes). Resting-state eyes-open and eyes-closed EEG was measured from 38 adults with ADHD, 45 first-degree relatives of people with ADHD and 51 unrelated controls. A machine learning classification analysis using penalized logistic regression (Elastic Net) examined if EEG spectral power (1-45 Hz) and TBR could classify participants into ADHD, first-degree relatives and/or control groups. Random-label permutation was used to quantify any bias in the analysis. Eyes-open absolute and relative EEG power distinguished ADHD from control participants (area under receiver operating characteristic = 0.71-0.77). The best predictors of ADHD status were increased power in delta, theta and low-alpha over centro-parietal regions, and in frontal low-beta and parietal mid-beta. TBR did not successfully classify ADHD status. Elevated eyes-open power in delta, theta, low-alpha and low-beta distinguished first-degree relatives from controls (area under receiver operating characteristic = 0.68-0.72), suggesting that these features may be a mediational endophenotype for adult ADHD. Resting-state EEG spectral power may be a neuromarker and mediational endophenotype of adult ADHD. These results did not support TBR as a diagnostic neuromarker for ADHD. It is possible that TBR is a characteristic of childhood ADHD.

Weekly Calendar Planning Activity for University Students: Comparison of Individuals With and Without ADHD by Gender

OBJECTIVE

To introduce a revised version of the Weekly Calendar Planning Activity (WCPA) adapted for university students (Weekly Calendar Performance Activity for students [WCPA-S]) and compare the performance of this activity between students with and without ADHD and across gender groups.

METHOD

Participants included a total of 157 students, ages 20 to 30, enrolled in universities/colleges and divided into two groups: students with ADHD (male = 23, female = 38) and without ADHD (male = 33, female = 63). A two-way ANOVA was used for data analyses. The WCPA-S was administered to each student individually.

RESULTS

Significant differences were found between students with and without ADHD and across genders in performance, duration of performance, and in the number of strategies used.

CONCLUSION

The WCPA-S proved to be an effective performance-based diagnostic tool for the utilization of executive functions in the daily life of university students. This instrument can be used to predict success in higher education and to support learning among university students with ADHD.

Posterior alpha oscillations reflect attentional problems in boys with Attention Deficit Hyperactivity Disorder

OBJECTIVE

This study aimed to characterize alpha modulations in children with ADHD in relation to their attentional performance.

METHODS

The posterior alpha activity (8-12Hz) was measured in 30 typically developing children and 30 children with ADHD aged 7-10years, using EEG while they performed a visuospatial covert attention task. We focused the analyses on typically developing boys (N=9) and boys with ADHD (N=17).

RESULTS

Alpha activity in typically developing boys was similar to previous results of healthy adults: it decreased in the hemisphere contralateral to the attended hemifield, whereas it relatively increased in the other hemisphere. However, in boys with ADHD this hemispheric lateralization in the alpha band was not obvious (group contrast, p=.018). A robust relation with behavioral performance was lacking in both groups.

CONCLUSIONS

The ability to modulate alpha oscillations in visual regions with the allocation of spatial attention was clearly present in typically developing boys, but not in boys with ADHD.

SIGNIFICANCE

These results open up the possibility to further study the underlying mechanisms of ADHD by examining how differences in the fronto-striatal network might explain different abilities in modulating the alpha band activity.