Severity of AD/HD symptoms and efficiency of attentional resource allocation.
This study investigated the mechanism that underlies the inefficient allocation of attentional resources in Attention-Deficit/Hyperactivity Disorder (AD/HD). The P300 event-related brain potential (ERP) was elicited from 24 healthy adults using a visual three-stimulus oddball paradigm (standard, 70%; target, 15%; non-target, 15%) and the degree of their AD/HD symptoms was assessed by using AD/HD symptom scales. Target stimulus was a circle and standard stimulus was an "X". Two task conditions were defined according to the non-target stimulus type (typical or novel): a triangle for the typical condition and colored non-repetitive novel stimuli for the novel condition. In both conditions, target and non-target elicited P300s. A ratio of non-target P300 to target P300 amplitude was used to assess the efficiency of attentional resource allocation; low ratio indicates the efficient allocation of attentional resource. The correlation analysis revealed a strong positive correlation between the AD/HD symptom score and the P300 amplitude ratio in the typical condition (r=.80), while only a weak positive correlation was observed in the novel condition (r=.23). The present study found that the commonality of task-relevant and task-irrelevant information, rather than the stimulus novelty of task-irrelevant information, induces the inefficient allocation of attentional resources in AD/HD.
Sawaki
Risa
R
Graduate School of Education, Hokkaido University, Kita-11 Nishi-7, Kita-ku, Sapporo 060-0811, Japan. sawaki@edu.hokudai.ac.jp
Katayama
Jun'ichi
J
D000328:Adult; D000704:Analysis of Variance; D001288:Attention / Q000502:physiology*; D001289:Attention Deficit Disorder with Hyperactivity / Q000503:physiopathology*; D001931:Brain Mapping; D004569:Electroencephalography / Q000379:methods; D018913:Event-Related Potentials, P300 / Q000502:physiology*; D005260:Female; D006801:Humans; D008297:Male; D010775:Photic Stimulation / Q000379:methods; D011597:Psychomotor Performance / Q000502:physiology*; D011930:Reaction Time / Q000502:physiology; D012720:Severity of Illness Index; D013647:Task Performance and Analysis