Clinical Psychology, Campus Bio-Medico University, Rome, Italy/LIRH Foundation, Rome, Italy.
Department of Life, Health and Environmental Sciences, University of L'Aquila, L'Aquila, Italy.
Mult Scler. 2018 Sep;24(10):1328-1336. doi: 10.1177/1352458517719149. Epub 2017 Jul 5.
Cognitive dysfunction affects 40%-65% of multiple sclerosis (MS) patients, most often affecting information processing speed and working memory, mediated by the pre-frontal cortex (PFC).
Our study aimed to investigate PFC functioning through a task-switching protocol in relapsing-remitting multiple sclerosis (RRMS) patients without cognitive impairment.
A total of 24 RRMS patients and 25 controls were enrolled. Two different tasks were performed in rapid and random succession, so that the task was either changed from one trial to the next one (switch trials) or repeated (repetition trials). Switch trials are usually slower than repetitions, causing a so-called switch cost (SC).
Patients had worse performance than controls only in the switch trials, as indicated by increased SC and reaction times. Moreover, patients showed a reduced ability to reconfigure the task-set for the execution of a new task and to disengage from the previous one.
Our results showed a primary deficit in executive control processes involved in the task-switching performance in RRMS patients without cognitive impairment. This deficit may depend on the functional impairment of the PFC, which is essential to adjust behaviour rapidly and flexibly in response to environmental changes, representing one of the most sophisticated human abilities.
认知功能障碍影响 40%-65%的多发性硬化症（MS）患者，最常见的是影响信息处理速度和工作记忆，由前额叶皮层（PFC）介导。
我们的研究旨在通过任务转换协议研究无认知障碍的复发缓解型多发性硬化症（RRMS）患者的 PFC 功能。
共纳入 24 名 RRMS 患者和 25 名对照者。两种不同的任务快速且随机地连续进行，因此任务要么从一次试验转换到下一次（转换试验），要么重复（重复试验）。转换试验通常比重复试验慢，导致所谓的转换成本（SC）。
患者的表现仅在转换试验中比对照组差，表现为 SC 和反应时间增加。此外，患者表现出降低的能力来重新配置任务集以执行新任务，并从先前的任务中解脱出来。
我们的结果表明，RRMS 患者无认知障碍的任务转换表现中存在执行控制过程的主要缺陷。这种缺陷可能取决于 PFC 的功能障碍，这对于根据环境变化快速灵活地调整行为至关重要，代表了人类最复杂的能力之一。
