Modulation of transcallosally mediated motor inhibition in children with attention deficit hyperactivity disorder (ADHD) by medication with methylphenidate (MPH)
Modulation of transcallosally mediated motor inhibition in children with attention deficit hyperactivity disorder (ADHD) by medication with methylphenidate (MPH)
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DOI：
10.1016/j.neulet.2006.06.026
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发表时间：
2006-09-11
影响因子：
2.5
通讯作者：
Wolters, A.
中科院分区：
文献类型：
--
作者：
Buchmann, J.;Gierow, W.;Wolters, A.
运动多动是注意缺陷多动障碍（ADHD）最突出的症状之一，可能是由抑制性运动控制障碍引起的。使用局灶性经颅磁刺激（TMS），我们测试了23名ADHD儿童（平均年龄11 +/- 2.6岁）在哌甲酯（MPH）治疗前和治疗中的皮质胼胝体抑制（同侧沉默期的持续时间和潜伏期，iSP）。iSP潜伏期与年龄相关，而iSP持续时间以及Conners评分与年龄无关。平均差异分析显示，用药组iSP持续时间显著延长（p = 0.001），iSP潜伏期显著缩短（p = 0.027），Conners评分显著降低（P = 0.001）。用药后iSP持续时间延长与Conners评分降低显著相关（t=-9.87，p = 0.016）。ADHD儿童的iSP持续时间缩短和iSP潜伏期延长可能是经胼胝体介导的抑制紊乱的结果，最可能的原因是胼胝体纤维束的成熟缺陷以及同侧刺激皮质层III（经胼胝体运动皮质纤维的起源）和对侧皮质层V（锥体束的起源）之间的神经元网络内的神经元突触传递。MPH可能通过纹状体-丘脑-皮质环的多巴胺能调节作用间接改善该神经元网络的兴奋性和抑制性神经元间活动之间的失衡。(c)2006爱思唯尔爱尔兰有限公司保留所有权利。
Motor hyperactivity is one of the most outstanding symptoms of attention deficit hyperactivity disorder (ADHD) which might be caused by a disturbed inhibitory motor control. Using focal transcranial magnetic stimulation (TMS) we tested the cortico-callosal inhibition (duration and latency of the ipsilateral Silent Period, iSP) in 23 children with ADHD (mean age 11 +/- 2.6 years) before and on treatment with methylphenidate (MPH). iSP latency was age correlated, whereas iSP duration as well as Conners scores were age independent. Analyses of mean differences revealed a significant prolongation of iSP duration (p = 0.001), shortening of iSP latency (p = 0.027) and reduction of Conners score (P = 0.001) under medication. Increase of iSP duration and reduction of Conners score under medication were significantly correlated (t= -9.87, p = 0.016). Reduced iSP duration and prolonged iSP latency in ADHD children could be the result of a disturbed transcallosally mediated inhibition, most probable due to a combination of maturation deficits of callosal fiber tracts as well as neuronal synaptical transmission within the neuronal network between ipsilaterally stimulated cortex layer III - the origin of transcallosal motor-cortical fibers - and contralateral layer V, the origin of the pyramidal tract. MPH may indirectly improve the dysbalance between excitatory and inhibitory interneuronal activities of this neuronal network via dopaminergic modulatory effects of the striato-thalamo-cortical loop. (c) 2006 Elsevier Ireland Ltd. All rights reserved.