Time-frequency representations of electroencephalographic signals lend themselves to granular analysis of cognitive and psychological processes. Characterizing developmental trajectories of time-frequency measures can thus inform us about the development of the processes involved. We decomposed EEG activity in a large sample of individuals (N = 1692; 917 females) assessed at approximately three-year intervals from the age of 11 to their mid-20s. Participants completed an oddball task that elicits a robust P3 response. Principal component analysis served to identify meaningful dimensions of time-frequency energy. Component loadings were virtually identical across assessment waves. A common and stable set of time-frequency dynamics thus characterized EEG activity throughout this age range. Trajectories of change in component scores suggest that aspects of brain development reflected in these components comprise two distinct phases, with marked decreases in component amplitude throughout much of adolescence followed by smaller yet significant rates of decreases into early adulthood. Although the structure of time-frequency activity was stable throughout adolescence and early adulthood, we observed subtle change in component loadings as well. Our findings suggest that striking developmental change in event-related potentials emerges through gradual change in the magnitude and timing of a stable set of dimensions of time-frequency activity, illustrating the usefulness of time-frequency representations of EEG signals and longitudinal designs for understanding brain development. In addition, two components were associated with childhood externalizing psychopathology, independent of sex, which extends the existing literature and provides proof of concept of the notion that developmental trajectories might serve as candidate endophenotypes for psychiatric disorders.
Time-Frequency Intracranial Source Localization of Feedback-Related EEG Activity in Hypothesis Testing
