Infant attention and frontal EEG neuromarkers of childhood ADHD

Abstract

Numerous electroencephalogram (EEG) studies have sought to elucidate the neural mechanisms of attention deficit hyperactivity disorder (ADHD), with most of the existing literature focused on children, adolescents, and adults. In this retrospective study, measures of frontal EEG power and behavioral attention of 40 5-month-old infants later diagnosed with ADHD in childhood were compared to 40 systematically matched-control infants. Compared to the control group, infants in the ADHD group exhibited longer looking fixations during an attention task. Frontal EEG power in the 6-9 Hz infant alpha band was lower in the ADHD group compared to the control group. Mean frontal EEG power was associated with visual fixations, underscoring specific attention behavior corresponding to frontal brain development in infancy. Infants later diagnosed with ADHD exhibited higher attention problems in childhood at ages 4 and 9 compared to the control group, and longer looking fixations in infancy were associated with higher childhood ADHD-related symptomatology. These findings suggest that decreased infant frontal EEG power and looking fixations as early as 5-months of age may serve as important early markers of later ADHD and can aid in building a more comprehensive model of ADHD from a developmental neuroscience approach.

Keywords: ADHD; Attention; Childhood; EEG; Frontal lobe; Infancy.

Graphical abstract

Fig. 1

Paired box plot of looking duration in the ADHD and control groups. Boxplot center line identifies the median, the upper whiskers extend from the 75th percentile to the 75th percentile + 1.5 interquartile range, the lower whiskers extend from the 25th percentile to the 25th–1.5 interquartile range. Note: Outliers not displayed (R Core Team, 2024).

Fig. 2

Paired box plot of the mean frontal EEG activity during the attention task for the alpha band, by group. Boxplot center line identifies the median, the upper whiskers extend from the 75th percentile to the 75th percentile + 1.5 interquartile range, the lower whiskers extend from the 25th percentile to the 25th–1.5 interquartile range.

Fig. 3

Topographic EEG maps detailing group-averaged EEG Power (referenced to F3 and F4 for the left and right hemisphere, respectively) for the Alpha 6–9 Hz frequency band during the attention task. Legend is shown by the color bar. Note: μV = microvolts.

Fig. 4

Scatterplot of correlation between behavioral attention task performance and EEG power. Longer looking durations were negatively associated with mean EEG power in the alpha frequency band. Shaded region represents the 95 % confidence interval of the prediction line.

Fig. 5

Paired box plots of attention problems assessed by the scores of the Child Behavior Checklist (Achenbach, 2001) Attention Problems Syndrome Scale and DSM-oriented and Syndrome Scale at ages 4 and 9, by group. Boxplot center line identifies the median, the upper whiskers extend from the 75th percentile to the 75th percentile + 1.5 interquartile range, the lower whiskers extend from the 25th percentile to the 25th–1.5 interquartile range. Data points were jittered in R by 0.02 to prevent overplotting (R Core Team, 2024).