Event-Related Potentials During a Delayed Match-to-Sample Test to Evaluate Working Memory Development in Control and Attention Deficit Children and Adolescents

Abstract

Working memory (WM) impairment is a core feature of attention deficit disorder (ADD). Differences in event-related potentials (ERPs) amplitude with respect to controls would permit to characterize neurophysiologically WM processing in ADD. Thirty-two ADD-diagnosed subjects and thirty-eight controls (6-17 years old) were recorded during a visual delayed match-to-sample test (DMTS). ERP amplitudes of ADD and control subjects were compared during the encoding, retention, and matching phases. Cluster mass permutation test, controlling for multiple comparisons in time and space (electrodes), showed statistically significant lower amplitude for the negative slow wave (NSW) in ADD children compared to the control group during the retention period. Electrodes CP6, P4, and P8 showed these significant differences. The lower amplitude of the NSW in ADD children suggests a dysfunctional activation of the WM, possibly related to the difficulty to focus attention during the coding and retention phases.