Study between supraliminal and subliminal N-back task in the children with symptoms of attention-deficit/ hyperactivity disorder

Abstract

Objective To explore the mechanisms underlying supraliminal and subliminal N-back task in the children with symptoms of attention-deficit/hyperactivity disorder (ADHD). Methods Thirty-five ADHD children and thirty-three matched normal controls were enrolled.Working memory was measured with the different reaction time of N-back task. Results The error number of the subliminal 2-back task in ADHD group((4.49±1.20)times) was worse than that of the healthy controls ((3.79±1.14)times), and the difference was significant(t=-2.459, P=0.017). In ADHD group, the error number of 1-back task and reaction time of 2-back task in subliminal task ((4.77±1.09)times, (1 447.49±271.35)ms) were worse than those of supraliminal task ((3.09±1.63)times, (1 315.48±229.63)ms), and the difference was significant between the two tasks (t=4.755, P=0.000; t=-2.281, P=0.029). But there were no significant findings in healthy controls(P>0.05). Conclusion The present study suggests that the working memory is impaired in ADHD children. Key words: Attention deficit hyperactivity disorder; Cognition; Memory