Department of Neurology, Vanderbilt University, Nashville, TN 37232, USA.
J Psychiatry Neurosci. 2013 Sep;38(5):349-56. doi: 10.1503/jpn.120138.
Evidence that tic behaviour in individuals with Tourette syndrome reflects difficulties inhibiting prepotent motor actions is mixed. Response conflict tasks produce sensitive measures of response interference from prepotent motor impulses and the proficiency of inhibiting these impulses as an act of cognitive control. We tested the hypothesis that individuals with Tourette syndrome show a deficit in inhibiting prepotent motor actions.
Healthy controls and older adolescents/adults with persistent Tourette syndrome without a history of obsessive-compulsive disorder or attention-deficit/hyperactivity disorder and presenting with stable mood functioning (i.e., no history of well-treated anxiety or depression) participated in this study. They performed a Simon task that induced conflict between prepotent actions and goal-directed actions. A novel theoretical framework distinguished group differences in acting impulsively (i.e., fast motor errors) from the proficiency of inhibiting interference by prepotent actions (i.e., slope of interference reduction).
We included 27 controls and 28 individuals with Tourette syndrome in our study. Both groups showed similar susceptibility to making fast, impulsive motor errors (Tourette syndrome 26% v. control 23%; p = 0.10). The slope (m) reduction of the interference effect was significantly less pronounced among participants with Tourette syndrome than controls (Tourette syndrome: m = -0.07 v. control: m = -0.23; p = 0.022), consistent with deficient inhibitory control over prepotent actions in Tourette syndrome.
This study does not address directly the role of psychiatric comorbidities and medication effects on inhibitory control over impulsive actions in individuals with Tourette syndrome.
The results offer empirical evidence for deficient inhibitory control over prepotent motor actions in individuals with persistent Tourette syndrome with minimal to absent psychiatric comorbidities. These findings also suggest that the frontal-basal ganglia circuits involved in suppressing unwanted motor actions may underlie deficient inhibitory control abilities in individuals with Tourette syndrome.
个体在患有图雷特综合征时的抽搐行为反映了抑制优势运动动作的困难，这方面的证据是混杂的。反应冲突任务会产生对优势运动冲动的反应干扰的敏感测量值，以及作为认知控制行为抑制这些冲动的熟练程度。我们检验了这样一个假设，即患有图雷特综合征的个体在抑制优势运动动作方面存在缺陷。
健康对照者和年龄较大的青少年/成年患者患有持续性图雷特综合征，无强迫症或注意缺陷多动障碍病史，且心境稳定（即无治疗良好的焦虑或抑郁病史），参加了这项研究。他们执行了一个 Simon 任务，该任务在优势动作和目标导向动作之间引起了冲突。一个新的理论框架区分了在冲动行为（即快速运动错误）和抑制优势动作干扰的熟练程度（即干扰减少的斜率）方面的组间差异。
我们的研究纳入了 27 名对照者和 28 名患有图雷特综合征的个体。两组都表现出类似的易受快速、冲动运动错误影响的倾向（图雷特综合征 26%，对照者 23%；p = 0.10）。与对照组相比，图雷特综合征患者的干扰效应斜率（m）降低明显不明显（图雷特综合征：m = -0.07，对照组：m = -0.23；p = 0.022），这与图雷特综合征中对优势动作的抑制控制不足一致。
本研究并未直接探讨精神病合并症和药物对图雷特综合征患者冲动行为抑制控制的作用。
这些结果为患有持续性图雷特综合征且伴有最小至无精神病合并症的个体中对优势运动动作的抑制控制不足提供了经验证据。这些发现还表明，涉及抑制不想要的运动动作的额-基底神经节回路可能是图雷特综合征患者抑制控制能力不足的基础。
