Spirou Angela, Liu Pei-Pei, Natsheh Joman Y, Neuteboom Eliane, Dobryakova Ekaterina
Traumatic Brain Injury Research, Kessler Foundation, East Hanover, NJ, United States.
Department of Physical Medicine and Rehabilitation, Rutgers New Jersey Medical School, Newark, NJ, United States.
Front Neurol. 2018 Jul 25;9:572. doi: 10.3389/fneur.2018.00572. eCollection 2018.
Outcome anticipation is not only a mental preparation for upcoming consequences, but also an essential component of learning and decision-making. Thus, anticipation of consequences is a key process in everyday functioning. The striatum and the ventromedial prefrontal cortex are among the key regions that have been shown to be involved in outcome anticipation. However, while structural abnormalities of these regions as well as altered decision-making have been noted in individuals with multiple sclerosis (MS), neural correlates of outcome anticipation have not been explored in this population. Thus, we examined the neural correlates of outcome anticipation in MS by analyzing brain activation in individuals with MS while they performed a modified version of a card-guessing task. Seventeen MS and 13 healthy controls performed the task while functional magnetic resonance imaging (fMRI) was obtained. To achieve maximal anticipatory response and prevent the possibility of differential performance on the task, participants were presented with monetary rewards only on 50% of the trials. While replicating previous evidence of structural abnormalities of the striatum in MS, our results further showed that individuals with MS exhibited greater activation in the putamen, right hippocampus, and posterior cingulate cortex during outcome anticipation compared to healthy controls. Furthermore, even though there was no strategy that participants could learn in order to predict outcomes, 76% of participants with MS indicated that they used strategies while performing the task. We thus propose that the increased neural activation observed in MS during outcome anticipation might be explained by a failure in recognizing the lack of regularity in the task structure that could result in using strategies to perform the task.
结果预期不仅是对即将到来的后果的心理准备，也是学习和决策的重要组成部分。因此，对后果的预期是日常功能中的一个关键过程。纹状体和腹内侧前额叶皮层是已被证明参与结果预期的关键区域。然而，虽然在多发性硬化症（MS）患者中已注意到这些区域的结构异常以及决策改变，但尚未在该人群中探索结果预期的神经关联。因此，我们通过分析MS患者在执行猜牌任务的修改版时的大脑激活情况，研究了MS患者结果预期的神经关联。17名MS患者和13名健康对照在进行功能磁共振成像（fMRI）时执行该任务。为了实现最大的预期反应并防止任务表现出现差异的可能性，仅在50%的试验中向参与者提供金钱奖励。在重复先前关于MS患者纹状体结构异常的证据时，我们的结果进一步表明，与健康对照相比，MS患者在结果预期期间壳核、右侧海马体和后扣带回皮层表现出更大的激活。此外，尽管参与者没有可以学习的预测结果的策略，但76%的MS患者表示他们在执行任务时使用了策略。因此，我们提出，在MS患者结果预期期间观察到的神经激活增加可能是由于未能识别任务结构中缺乏规律性，这可能导致使用策略来执行任务。
