Visual Search in Chinese Children With Attention Deficit/Hyperactivity Disorder and Comorbid Developmental Dyslexia: Evidence for Pathogenesis From Eye Movements

Abstract

In this study, a visual search task was conducted on children with comorbid attention deficit/hyperactivity disorder (ADHD) and developmental dyslexia (DD), children with pure ADHD, and typically developing children to explore the pathogenesis of comorbidity between ADHD and DD. Participants searched for the target character from five characters in each trial during the task. The distractors included orthographically similar characters, homophones, unrelated characters, and characters of a different color (i.e., red). Results showed that the clinical groups produced longer first fixation duration than the control group in all types of distractors. Children with ADHD comorbid DD were also more susceptible to characters with the distracting red color in gaze duration and total viewing time than were children with pure ADHD and healthy controls. The implication of comorbidity (ADHD + DD) on the pathogenesis was discussed. These results may be helpful for the diagnosis and treatment of ADHD with comorbid DD.

Visual search in neurodevelopmental disorders: evidence towards a continuum of impairment

“…Noteworthy, and differently from SCZ, fixation duration paralleled typical duration of search and scanning time, suggesting that ADHD might have had more cognitive resources than SCZ to perform the task efficiently, while opting for a focal search strategy, like SCZ. Only two other studies have assessed VS in children with ADHD including fixation-related measures [ 48 , 63 ]. Cui et al [ 63 ] found prolonged first fixation duration but typical gaze duration (as the sum of all fixation durations), which resembles the finding of typical search duration found here, leading to atypical search processing limited to an early stage of search in ADHD.…”

“…Only two other studies have assessed VS in children with ADHD including fixation-related measures [ 48 , 63 ]. Cui et al [ 63 ] found prolonged first fixation duration but typical gaze duration (as the sum of all fixation durations), which resembles the finding of typical search duration found here, leading to atypical search processing limited to an early stage of search in ADHD. In contrast to the present finding, Seernani et al [ 47 ] reported typical average fixation duration per trial in the ADHD group.…”

Potential Logographic Dyslexics Identified via Self-Reporting during a Questionnaire Survey in Taiwan

“…Each of our cases revealed specific symptoms of dyslexia. Case D1 has deficits of reading skills, which is probably related to ADHD [15]. Also, both of D2 and D3 are more energetic in the evening than in the daytime, in addition to reading and writing impairments.…”

“…Dyslexia may happen together with autism [14] and/or attention deficit hyperactivity disorder (ADHD) [15]. The proband has normal intelligence but seems to be a spectrum with different severities [16].…”

“…The predominant opinions agree that genes [19][20][21] and brain [16] are two areas to focus on [22]. The potential risk loci located on chromosome 1, 2,3,4,6,11,12,13,15,17,18, and X [19]. Apparently, it is polygenetic.…”