Electrophysiological Correlates of Response Time Variability During a Sustained Attention Task

Area of Science:

• Neuroscience
• Cognitive Psychology
• Developmental Psychology

Background:

• Attention Deficit Hyperactivity Disorder (ADHD) is associated with heightened Response Time Variability (RTV) during cognitive tasks.
• Inefficient brain functional connectivity is hypothesized to underlie increased RTV in individuals with ADHD.

Purpose of the Study:

• To investigate the relationship between brain connectivity, RTV, and ADHD symptom severity.
• To explore age-related differences in RTV and brain network efficiency between children and adolescents with ADHD.

Main Methods:

• EEG recording during the Sustained Attention to Response Task (SART) in 28 children and 49 adolescents with ADHD.
• Ex-Gaussian analysis and Fast Fourier Transform to quantify RTV.
• Calculation of global efficiency and modularity from functional connectivity data to assess brain network integration and segregation.

Main Results:

• A positive association was found between RTV measures and ADHD symptom levels.
• Greater global efficiency of brain networks was linked to reduced RTV.
• Children exhibited higher RTV and less efficient brain networks compared to adolescents.

Conclusions:

• Findings support the hypothesis that inefficient brain connectivity contributes to RTV in ADHD.
• More integrated and efficient brain networks are associated with more stable cognitive performance.
• Age influences both RTV and brain network efficiency in ADHD.