Abstract:
Objective: In the current study, we explored the neural substrate for acute effects of guanfacine extended release (GXR) on inhibitory control in school-aged children with attention deficit hyperactivity disorder (ADHD), using functional near-infrared spectroscopy (fNIRS). Methods: Following a GXR washout period, 12 AD HD children (6-10 years old) performed a go/no-go task before and 3 h after GXR or placebo administration, in a randomized, double-blind, placebo-controlled, crossover design study. In the primary analysis, fNIRS was used to monitor the right prefrontal cortical hemodynamics of the participants, where our former studies showed consistent dysfunction and osmotic release oral system-methylphenidate (OROS-MPH) and atomoxetine hydrochloride (ATX) elicited recovery. We examined the inter-medication contrast, comparing the effect of GXR against the placebo. In the exploratory analysis, we explored neural responses in regions other than the right prefrontal cortex (PFC). Results: In the primary analysis, we observed no significant main effects or interactions of medication type and age in month (two-way mixed ANCOVA, Fs < 0.20, all ps > .05). However, in the post-hoc analysis, we observed significant change in the oxy-Hb signal in the right angular gyrus (AG) for inter-medication (one sample t-test, p < 0.05, uncorrected, Cohen\'s d = 0.71). Conclusions: These results are different from the neuropharmacological effects of OROS-MPH and ATX, which, in an upregulated manner, reduced right PFC function in ADHD children during inhibitory tasks. This analysis, while limited by its secondary nature, suggested that the improved cognitive performance was associated with activation in the right AG, which might serve as a biological marker to monitor the effect of GXR in the ADHD children.
摘要:
目的:在目前的研究中,我们探索了胍法辛缓释剂(GXR)对注意缺陷多动障碍(ADHD)学龄儿童的抑制控制的急性作用的神经底物,使用功能近红外光谱(fNIRS)。方法:在GXR清除期后,12名ADHD儿童(6-10岁)在GXR或安慰剂给药前和给药后3小时进行了去/去任务,在一个随机的,双盲,安慰剂对照,交叉设计研究。在初步分析中,fNIRS用于监测参与者的右前额皮质血流动力学,我们以前的研究表明,持续的功能障碍和渗透释放口服系统-哌醋甲酯(OROS-MPH)和盐酸托莫西汀(ATX)引起了恢复。我们检查了药物间的对比,比较GXR与安慰剂的效果。在探索性分析中,我们研究了右侧前额叶皮层(PFC)以外区域的神经反应.结果:在初步分析中,我们没有观察到药物类型和月龄的显著主要影响或相互作用(双向混合ANCOVA,Fs<0.20,所有ps>.05)。然而,在事后分析中,我们观察到药物间右回(AG)中oxy-Hb信号的显着变化(一个样本t检验,p<0.05,未校正,科恩的d=0.71)。结论:这些结果与OROS-MPH和ATX的神经药理作用不同,which,以一种上调的方式,抑制任务期间ADHD儿童的右PFC功能降低。这个分析,虽然受限于其次要性质,提示认知表现的改善与右AG的激活有关,这可能作为监测GXR在ADHD儿童中的作用的生物学标记。