Deficient interference control during working memory updating in adults with ADHD: An event-related potential study

Area of Science:

• Neuroscience
• Cognitive Psychology
• Psychiatry

Background:

• Working memory (WM) deficits are common in adults with attention deficit hyperactivity disorder (ADHD).
• The specific neural mechanisms underlying these WM impairments remain largely unknown.
• Understanding these mechanisms is crucial for developing targeted interventions.

Purpose of the Study:

• To investigate the electrophysiological underpinnings of impaired WM updating in adults with ADHD.
• To examine the roles of interference control and WM load in ADHD-related WM deficits.
• To differentiate between interference and load effects using event-related potentials (ERPs).

Main Methods:

• Forty adults with ADHD and 41 healthy controls completed verbal n-back tasks.
• Tasks involved conditions of low and high WM load.
• Intrusion probes (lures) were used to assess interference control during WM updating.

Main Results:

• Adults with ADHD exhibited reduced stimulus-dependent N200 amplitude modulation compared to controls.
• Behavioral performance in trials with lures was poorer in the ADHD group.
• P300 amplitudes showed less sensitivity to WM load variations in individuals with ADHD.

Conclusions:

• Findings suggest electrophysiological evidence of inaccurate stimulus discrimination in adult ADHD.
• Deficient interference control appears to be a key factor contributing to WM deficits in adult ADHD.
• This research deepens the understanding of executive dysfunction in adult ADHD, specifically within the WM domain.