Abstract
ADHD is a chronic mental health condition defined by behavioral symptoms of inattention, hyperactivity and impulsivity. Such definition completely ignores the cognitive deficits underlying ADHD. Moreover, ADHD symptoms (e.g. 'is easily distracted', 'cannot wait for his/her turn') are not exclusive to ADHD and may be present in various conditions. In order to better understand the diverse cognitive profiles among children with ADHD, our study examined approximately 80 children, 8-12 years-old, diagnosed with ADHD by a qualified clinician. Based on previous studies that focused on impaired cognitive mechanisms in ADHD, the following cognitive tests were administered: (1) Continuous Performance Test (CPT) to assess sustained attention; (2) conjunctive visual search task to assess selective-spatial attention; (3) spatial precueing task to assess orienting of attention; (4) spatial Stroop-like task to assess executive attention; (5) Wechsler's digit span forward and backward to assess the phonological loop and the central executive (CE) components of the Working Memory (WM) system, respectively; and (6) Corsi-Block task forward and backward to assess the visual-spatial sketchpad and the CE components of the WM, respectively. Based on data of age-matched typically developing (TD) children, collected in our lab in previous studies, we classified the performance of each participant on each cognitive task as either impaired (lower 10% of TD children) or intact. Various frequencies of impairments were obtained in different cognitive functions, ranging from 17% in selective-spatial attention, up to 56% in sustained attention. While a substantial sub-group of participants showed impairment in more than one cognitive function, another sub-group of participants demonstrated intact performance on all the above cognitive tasks. Our findings provide further support for theories that assume that ADHD is a heterogeneous disorder and highlight the importance of comprehensive assessment using neuropsychological tasks in advancing the ability to design personally adjusted interventions for individuals with ADHD.
Meeting abstract presented at VSS 2018