Evoked Potentials Differentiate Developmental Coordination Disorder From Attention-Deficit/Hyperactivity Disorder in...

Area of Science:

• Neurodevelopmental Disorders
• Cognitive Neuroscience
• Clinical Psychology

Background:

• Developmental Coordination Disorder (DCD) and Attention-Deficit/Hyperactivity Disorder (ADHD) are neurodevelopmental disorders with overlapping executive function and motor control deficits.
• These conditions co-occur in up to 50% of cases, necessitating research into their distinct pathological mechanisms, especially in adults.
• Limited research exists on the adult overlap of DCD and ADHD, particularly concerning executive functions and motor control.

Purpose of the Study:

• To investigate executive functions and motor control in adults with DCD, ADHD, co-occurring DCD + ADHD, and typically developed controls.
• To identify behavioral and neurophysiological differences (using EEG and ERPs) between these groups.
• To explore potential endophenotypic differences in cognitive control and response inhibition.

Main Methods:

• Utilized a stop-signal task with parallel electroencephalography (EEG) measurement in 50 adult participants.
• Assessed executive performance through go accuracy and reaction time, and motor response inhibition via stop-signal reaction time.
• Analyzed event-related potentials (ERPs), specifically N200 and P300 components, to examine neural activity during response inhibition.

Main Results:

• Replicated findings of no significant between-group differences in behavioral measures of executive performance and motor response inhibition.
• Observed significant differences in ERP components N200 and P300 between groups, particularly during successful response inhibition.
• These ERP differences suggest underlying neurophysiological distinctions not apparent in overt behavior.

Conclusions:

• Adults with DCD and/or ADHD exhibit distinct physiological responses related to executive functions and motor control, despite similar behavioral performance.
• Event-related potentials (ERPs) like N200 and P300 may serve as endophenotypes for differentiating ADHD and DCD.
• Findings suggest disorder-specific neural mechanisms for inhibition and executive functions in adults with DCD, ADHD, or both.