EEG and eye-fixation related potentials in children with ADHD

Abstract

Attention deficit hyperactivity disorder (ADHD) is common and difficult to diagnose. It involves symptoms that impair social, academic, and/or occupational functioning, such as difficulty sustaining attention, forgeting and frequent losingthings, impulsive decisions and excessive motor activity. These symptoms can lead to serious deterioration of everyday functioning. Diagnosis of ADHD may be problematic, subjective, and ambiguous due to gender(more common in boys than in girls) and age (more common in younger than older children) biases. Therefore,candidates for neuromarkers in children with ADHD have been sought for a long time. To date, structural (magnetic resonance imaging, MRI) and functional (functional magnetic resonance imaging, fMRI; electroencephalography, EEG) neuromarkers have been searched for – mostly without success. This is due, among other things, to different statistical methods used to analyse the results, different tasks, methods, and study groups, and the disregardof participants’ fatigue levels during the study. Therefore, incorporating objective neurophysiological measures recorded during an attentional task in the diagnosis of ADHD can be helpful in overcoming these problems. Electroencephalography (EEG)is particularly worth mentioning as it isa readilyavailable and no less promising tool that has already been extensively used in the diagnosis of ADHD. Equally important seems to be oculography, which has also come quite close to being recognisedas a biomarker of ADHD. Combining these measurements during a cognitive task could yealdnew insight into neurocognitive functions in ADHD and possible bioelectrical neuromarkers. We propose and discuss a set of hypotheses regarding EEG in children with ADHD; the hypotheses will be tested using the flanker task because it provides a measures of processing inhibition and interference control and is generally considered a factor ofinattention. We will propose and discuss in detail the research hypotheses to be implemented investigating the neurocognitive correlates of ADHD.