Xu Hui, Zhang Xiuping, Bai Guanghui
Department of Radiology, The Second Affiliated Hospital and Yuying Children's Hospital of Wenzhou Medical University, Wenzhou 325027, China.
Research Center, Institut Universitaire de Gériatrie de Montréal, Montreal, QC H3W 1W5, Canada.
J Clin Med. 2022 Apr 28;11(9):2484. doi: 10.3390/jcm11092484.
Mild traumatic brain injury (mTBI) is an important but less recognized public health concern. Previous studies have demonstrated that patients with mTBI have impaired executive function, which disrupts the performance of daily activities. Few studies have investigated neural mechanisms of cognitive flexibility in mTBI patients using objective tools such as the psychological experiment paradigm. Here, we aimed to examine neural correlates of cognitive flexibility in mTBI.
Sixteen mTBI patients and seventeen matched healthy controls (HCs) underwent functional MRI during a rule-based task-switching experimental paradigm. Linear models were used to obtain within-group activation maps and areas of differential activation between the groups. In addition, we conducted mediation analyses to evaluate the indirect effect of abnormal dorsal caudate activation on the association between information processing speed and cognitive flexibility in mTBI.
mTBI patients exhibited significantly longer reaction time in the task switching (TS) condition compared to HCs, reflecting impaired cognitive flexibility. In addition, the patients showed reduced activation in the dorsal caudate (dCau), anterior cingulate cortex, and other frontal regions during the TS condition. Mediation analysis revealed that the reduced dCau activation had a significant effect on the relationship between information processing speed and cognitive flexibility in mTBI.
Abnormal dorsal caudate activation in mTBI mediates impaired cognitive flexibility, which indicated dorsal caudate might be playing a vital role in the cognitive flexibility of mTBI patients. These findings highlight an alternative target for clinical interventions for the improvement of cognitive functions in mTBI.
轻度创伤性脑损伤（mTBI）是一个重要但未得到充分认识的公共卫生问题。先前的研究表明，mTBI患者存在执行功能受损，这会干扰日常活动的表现。很少有研究使用心理实验范式等客观工具来探究mTBI患者认知灵活性的神经机制。在此，我们旨在研究mTBI中认知灵活性的神经关联。
16名mTBI患者和17名匹配的健康对照（HCs）在基于规则的任务切换实验范式中接受了功能磁共振成像。使用线性模型获得组内激活图和组间差异激活区域。此外，我们进行了中介分析，以评估背侧尾状核异常激活对mTBI患者信息处理速度与认知灵活性之间关联的间接影响。
与HCs相比，mTBI患者在任务切换（TS）条件下的反应时间显著更长，这反映了认知灵活性受损。此外，患者在TS条件下背侧尾状核（dCau）、前扣带回皮质和其他额叶区域的激活减少。中介分析表明，dCau激活减少对mTBI患者信息处理速度与认知灵活性之间的关系有显著影响。
mTBI中背侧尾状核异常激活介导了认知灵活性受损，这表明背侧尾状核可能在mTBI患者的认知灵活性中起着至关重要的作用。这些发现突出了一个用于改善mTBI认知功能的临床干预替代靶点。
