Dettwiler Annegret, Murugavel Murali, Putukian Margot, Cubon Valerie, Furtado John, Osherson Daniel
1 Princeton Neuroscience Institute, Princeton University , Princeton, New Jersey.
J Neurotrauma. 2014 Jan 15;31(2):180-8. doi: 10.1089/neu.2013.2983. Epub 2013 Oct 17.
Avoiding recurrent injury in sports-related concussion (SRC) requires understanding the neural mechanisms involved during the time of recovery after injury. The decision for return-to-play is one of the most difficult responsibilities facing the physician, and so far this decision has been based primarily on neurological examination, symptom checklists, and neuropsychological (NP) testing. Functional magnetic resonance imaging (fMRI) may be an additional, more objective tool to assess the severity and recovery of function after concussion. The purpose of this study was to define neural correlates of SRC during the 2 months after injury in varsity contact sport athletes who suffered a SRC. All athletes were scanned as they performed an n-back task, for n=1, 2, 3. Subjects were scanned within 72 hours (session one), at 2 weeks (session two), and 2 months (session three) post-injury. Compared with age and sex matched normal controls, concussed subjects demonstrated persistent, significantly increased activation for the 2 minus 1 n-back contrast in bilateral dorsolateral prefrontal cortex (DLPFC) in all three sessions and in the inferior parietal lobe in session one and two (α≤0.01 corrected). Measures of task performance revealed no significant differences between concussed versus control groups at any of the three time points with respect to any of the three n-back tasks. These findings suggest that functional brain activation differences persist at 2 months after injury in concussed athletes, despite the fact that their performance on a standard working memory task is comparable to normal controls and normalization of clinical and NP test results. These results might indicate a delay between neural and behaviorally assessed recovery after SRC.
避免运动相关脑震荡（SRC）的反复损伤需要了解损伤后恢复期间涉及的神经机制。决定是否恢复运动是医生面临的最困难的职责之一，到目前为止，这一决定主要基于神经学检查、症状清单和神经心理学（NP）测试。功能磁共振成像（fMRI）可能是一种额外的、更客观的工具，用于评估脑震荡后功能的严重程度和恢复情况。本研究的目的是确定在遭受SRC的大学接触性运动运动员受伤后2个月内SRC的神经相关性。所有运动员在执行n-back任务（n = 1、2、3）时都接受了扫描。受试者在受伤后72小时内（第一阶段）、2周（第二阶段）和2个月（第三阶段）接受扫描。与年龄和性别匹配的正常对照组相比，脑震荡受试者在所有三个阶段的双侧背外侧前额叶皮层（DLPFC）中，对于2减1的n-back对比，均表现出持续且显著增加的激活，在第一阶段和第二阶段的顶下小叶中也是如此（α≤0.01校正）。任务表现的测量结果显示，在三个时间点中的任何一个时间点，脑震荡组与对照组在任何一项n-back任务上均无显著差异。这些发现表明，尽管脑震荡运动员在标准工作记忆任务上的表现与正常对照组相当，且临床和NP测试结果已恢复正常，但在受伤2个月后，其大脑功能激活差异仍然存在。这些结果可能表明SRC后神经恢复和行为评估恢复之间存在延迟。
