Distractibility in AD/HD predominantly inattentive and combined subtypes: the P3a ERP component, heart rate and performance.
The current study aimed to investigate whether children and adolescents diagnosed with Attention Deficit/Hyperactivity Disorder Predominantly Inattentive (AD/HD-in; Child n = 24, Adolescent n = 33) and Combined (AD/HD-com; Child n = 30, Adolescent n = 42) subtypes were more distractible than controls (Child n = 54; Adolescents n = 75), by assessing event-related potential (ERP), performance and peripheral arousal measures. All AD/HD groups displayed smaller amplitudes and/or shorter latencies of the P3a ERP component - thought to reflect involuntary attention switching - following task-deviant novel stimuli (checkerboard patterns) embedded in a Working Memory (WM) task. The P3a results suggested that both AD/HD-in and AD/HD-com subtypes ineffectively evaluate deviant stimuli and are hence more "distractible". These abnormalities were most pronounced over the central areas. AD/HD groups did not display any abnormalities in averaged heart rate over the WM task, a measure of peripheral arousal. They did display abnormalities in performance measures from the task, but these were unrelated to P3a abnormalities. AD/HD groups also displayed a number of deficits on Switching of Attention and Verbal Memory tasks, however, the pattern of abnormality mostly reflected general cognitive deficits rather than resulting from distraction.
Keage
Hannah A D
HA
Cognitive Neuroscience Laboratory, School of Psychology, Flinders University, SA 5042, Australia.
Clark
C Richard
CR
Hermens
Daniel F
DF
Kohn
Michael R
MR
Clarke
Simon
S
Williams
Leanne M
LM
Crewther
David
D
Lamb
Chris
C
Gordon
Evian
E
D000293:Adolescent; D000704:Analysis of Variance; D001288:Attention / Q000502:physiology*; D001289:Attention Deficit Disorder with Hyperactivity / Q000145:classification / Q000503:physiopathology*; D001932:Brain Neoplasms; D002648:Child; D004569:Electroencephalography / Q000379:methods; D005072:Evoked Potentials, Auditory / Q000502:physiology*; D005260:Female; D006339:Heart Rate / Q000502:physiology*; D006801:Humans; D008297:Male; D008570:Memory, Short-Term / Q000502:physiology; D009483:Neuropsychological Tests; D011597:Psychomotor Performance / Q000502:physiology*; D011930:Reaction Time / Q000502:physiology; D014706:Verbal Learning / Q000502:physiology