Reading performance in children with ADHD: an eye-tracking study

Increased Semantic Memorization in Children with ADHD during a Paradigm of Motor Priming: Exploratory Findings

AIM

The aim was to evaluate the effect of body actions on learning process, particularly semantic memory capabilities in drug-naïve children with attention deficit hyperactivity disorder (ADHD).

METHOD

Thirty children had to listen to a story which was repeated three times in a row and then a fourth time five minutes later. After each listen, the child was asked what she/he remembered from the story. The whole sample was split randomly into three subgroups of equal IQ (mean 102.2 ± 12.7), age (mean age 8 ± 0.6 years), sex (ratio female to male 1:5) and severity of ADHD symptoms (34.2 ± 7.4); a G1 "Freeze" subgroup, which implied listening to the story while sitting on a chair without moving; a G2 "Minimal" subgroup, which implied listening to the story while sitting on a chair but free movement was allowed; a G3 "Prescribed movement" subgroup, which implied listening to the story standing up, while copying the experimenter movements that mimicked the actions told in the story.

RESULTS

Although our sample was limited in size, interestingly, children in the G3 subgroup showed the highest short-term semantic memory retention compared to G1. In all subgroups, repetition allowed an increase in performance.

CONCLUSIONS

Our exploratory findings stress the positive role of movement in children with ADHD to increase semantic memorization. Hyperactivity may counteract the deficit of memorization related to attention impairment in children with ADHD. Our results may encourage parents or teachers to allow children with ADHD to move around during short-term memory-retention tasks.

Lévy Flight Model of Gaze Trajectories to Assist in ADHD Diagnoses

The precise mathematical description of gaze patterns remains a topic of ongoing debate, impacting the practical analysis of eye-tracking data. In this context, we present evidence supporting the appropriateness of a Lévy flight description for eye-gaze trajectories, emphasizing its beneficial scale-invariant properties. Our study focuses on utilizing these properties to aid in diagnosing Attention-Deficit and Hyperactivity Disorder (ADHD) in children, in conjunction with standard cognitive tests. Using this method, we found that the distribution of the characteristic exponent of Lévy flights statistically is different in children with ADHD. Furthermore, we observed that these children deviate from a strategy that is considered optimal for searching processes, in contrast to non-ADHD children. We focused on the case where both eye-tracking data and data from a cognitive test are present and show that the study of gaze patterns in children with ADHD can help in identifying this condition. Since eye-tracking data can be gathered during cognitive tests without needing extra time-consuming specific tasks, we argue that it is in a prime position to provide assistance in the arduous task of diagnosing ADHD.

Dyslexia: Causes and Concomitant Impairments

In recent decades, theories have been presented to explain the nature of dyslexia, but the causes of dyslexia remained unclear. Although the investigation of the causes of dyslexia presupposes a clear understanding of the concept of cause, such an understanding is missing. The present paper proposes the absence of at least one necessary condition or the absence of all sufficient conditions as causes for impaired reading. The causes of impaired reading include: an incorrect fixation location, too short a fixation time, the attempt to recognize too many letters simultaneously, too large saccade amplitudes, and too short verbal reaction times. It is assumed that a longer required fixation time in dyslexic readers results from a functional impairment of areas V1, V2, and V3 that require more time to complete temporal summation. These areas and areas that receive input from them, such as the fusiform gyrus, are assumed to be impaired in their ability to simultaneously process a string of letters. When these impairments are compensated by a new reading strategy, reading ability improves immediately.

Pathogenesis of Comorbid ADHD and Chinese Developmental Dyslexia: Evidence From Eye-Movement Tracking and Rapid Automatized Naming

BACKGROUND

ADHD and Chinese developmental dyslexia (DD) have a very high comorbidity rate; however, which cognitive deficits characterize the comorbidity and when they occur during cognitive processing are still under debate.

METHODS

Rapid automatic naming (RAN) tasks with eye-movement tracking were conducted with 75 children who were typically developing, had comorbid ADHD and DD, had only ADHD, and had only DD.

RESULTS

The clinical groups had longer first fixation durations than the control for RAN digits. Temporal eye-movement measures, such as gaze duration and total reading time, were found to vary between the comorbidity and ADHD groups. Spatial eye-movement measures, such as regression probability and incoming saccade amplitude, differed between the comorbidity and DD groups.

CONCLUSIONS

These results indicate that investigation with eye-movement measures combined with RAN tasks can strengthen the understanding of the pathogenesis of comorbid ADHD and DD.