Brandt Valerie C, Beck Christian, Sajin Valeria, Baaske Magdalena K, Bäumer Tobias, Beste Christian, Anders Silke, Münchau Alexander
Department of Paediatric and Adult Movement Disorders and Neuropsychiatry, Institute of Neurogenetics, University of Lübeck, Germany.
Department of Neurology, University of Lübeck, Germany.
Cortex. 2016 Apr;77:24-37. doi: 10.1016/j.cortex.2016.01.008. Epub 2016 Jan 23.
Premonitory urges are a cardinal feature in Tourette syndrome and are commonly viewed as the driving force of tics, building up before and subsiding after the execution of tics. Although the urge-tic interplay is one of the most preeminent features in Tourette syndrome, the temporal relationship between tics and urges has never been examined experimentally, mainly due to the lack of an appropriate assessment tool. We investigated the temporal relationship between urge intensity and tics in 17 Tourette patients and between urge intensity and eye blinks in 16 healthy controls in a free ticcing/blinking condition and a tic/blink suppression condition. For this purpose, an urge assessment tool was developed that allows real-time monitoring and quantification of urge intensity. Compared to free ticcing/blinking, urge intensity was higher during the suppression condition in both Tourette patients and healthy controls, while tics and blinks occurred less frequently. The data show that urge intensity increases prior to tics and decreases after tics in a time window of approximately ±10 sec. Tic suppression had a significant effect on the shape of the urge distribution around tics and led to a decrease in the size of the correlation between urge intensity and tics, indicating that tic suppression led to a de-coupling of tics and urges. In healthy controls, urges to blink were highly associated with eye blink execution, albeit in a narrower time frame (∼±5 sec). Blink suppression had a similar effect on the urge distribution associated with eye blinks as tic suppression had on the urge to tic in Tourette patients. These results corroborate the negative reinforcement model, which proposes that tics are associated with a relief in urges, thereby perpetuating ticcing behaviour. This study also documents similarities and differences between urges to act in healthy controls and urges to tic in Tourette syndrome.
预兆性冲动是抽动秽语综合征的一个主要特征，通常被视为抽动的驱动力，在抽动执行之前增强，在抽动执行之后减弱。尽管冲动与抽动的相互作用是抽动秽语综合征最显著的特征之一，但抽动与冲动之间的时间关系从未经过实验研究，主要是由于缺乏合适的评估工具。我们在自由抽动/眨眼状态和抽动/眨眼抑制状态下，研究了17名抽动秽语综合征患者的冲动强度与抽动之间的时间关系，以及16名健康对照者的冲动强度与眨眼之间的时间关系。为此，开发了一种冲动评估工具，可对冲动强度进行实时监测和量化。与自由抽动/眨眼相比，在抑制状态下，抽动秽语综合征患者和健康对照者的冲动强度均更高，而抽动和眨眼的发生频率更低。数据显示，在大约±10秒的时间窗口内，冲动强度在抽动之前增加，在抽动之后降低。抽动抑制对抽动周围冲动分布的形状有显著影响，并导致冲动强度与抽动之间的相关性大小降低，表明抽动抑制导致抽动与冲动脱钩。在健康对照者中，眨眼冲动与眨眼执行高度相关，尽管时间框架更窄（约±5秒）。眨眼抑制对与眨眼相关的冲动分布的影响，与抽动抑制对抽动秽语综合征患者抽动冲动的影响类似。这些结果证实了负强化模型，该模型提出抽动与冲动缓解相关，从而使抽动行为持续存在。本研究还记录了健康对照者的行动冲动与抽动秽语综合征患者的抽动冲动之间的异同。
