Korman Maria, Shaklai Sharon, Cisamariu Keren, Gal Carmit, Maaravi-Hesseg Rinatia, Levy Ishay, Keren Ofer, Karni Avi, Sacher Yaron
Edmond. J. Safra Brain Research Center for the Study of Learning Disabilities, University of Haifa, Haifa, Israel.
Loewenstein Rehabilitation Hospital, Ra'anana, Israel.
Front Hum Neurosci. 2018 Jan 30;12:10. doi: 10.3389/fnhum.2018.00010. eCollection 2018.
Using the finger-to-thumb opposition sequence (FOS) learning task, we characterized motor skill learning in sub-acute patients hospitalized for rehabilitation following traumatic brain injury (TBI). Ten patients (Trained TBI) and 11 healthy participants (Trained Healthy) were trained using a multi-session protocol: a single session was afforded in the first week of the study, and four daily sessions were afforded during the second week. Intensity of practice was adapted to patients. Performance speed and accuracy were tested before and after each session. Retention was tested 1 month later. Ten patients (Control TBI) had no FOS training and were tested only at the beginning and the end of the 6 week period. Although baseline performance on the FOS was very slow, all three phases of skill learning found in healthy adults (acquisition, between-session consolidation gains, and long-term retention) could be identified in patients with TBI. However, their time-course of learning was atypical. The Trained TBI group improved in speed about double the spontaneous improvements observed in the Control TBI group, with no speed-accuracy tradeoff. Normalized to their initial performance on the FOS, the gains accrued by the Trained TBI group after a first training were comparable to those accrued by healthy adults. Only during the second week with daily training, the rate of improvement of the Trained TBI group lagged behind that of the Trained Healthy group, due to increasing within-sessions losses in performance speed; no such losses were found in healthy participants. The Functional Independence Measure scores at the start of the study correlated with the total gains attained at the end of the study; no correlations were found with severity of injury or explicit memory impairments. Despite within-sessions losses in performance, which we propose reflect cognitive fatigue, training resulted in robust overall learning and long-term retention in patients with moderate-severe TBI. Given that the gains in performance evolved mainly between sessions, as delayed, offline, gains, our results suggest that memory consolidation processes can be effectively engaged in patients with TBI. However, practice protocols and schedules may need to be optimized to better engage the potential for long-term plasticity in these patients.
我们采用拇指对指序列（FOS）学习任务，对因创伤性脑损伤（TBI）住院康复的亚急性患者的运动技能学习进行了特征描述。10名患者（训练后的TBI患者）和11名健康参与者（训练后的健康人）采用多阶段方案进行训练：在研究的第一周进行一次训练，第二周每天进行四次训练。训练强度根据患者情况进行调整。在每次训练前后测试表现速度和准确性。1个月后测试记忆保持情况。10名患者（对照TBI患者）未接受FOS训练，仅在6周期间开始和结束时进行测试。尽管FOS任务的基线表现非常缓慢，但在TBI患者中可以识别出健康成年人中发现的技能学习的所有三个阶段（习得、训练期间巩固提升和长期记忆保持）。然而，他们的学习时间进程是非典型的。训练后的TBI组在速度上的提高约为对照TBI组自发提高的两倍，且不存在速度-准确性权衡。以他们在FOS任务上的初始表现进行标准化后，训练后的TBI组在首次训练后的提升与健康成年人相当。仅在第二周的每日训练期间，训练后的TBI组的提高速度落后于训练后的健康组，这是由于训练期间表现速度的损失增加；健康参与者中未发现此类损失。研究开始时的功能独立性测量得分与研究结束时获得的总提升相关；与损伤严重程度或明确的记忆障碍无关。尽管训练期间存在表现损失，我们认为这反映了认知疲劳，但训练导致中度至重度TBI患者实现了强大的整体学习和长期记忆保持。鉴于表现的提升主要在训练期间之间以延迟的、离线的提升形式出现，我们的结果表明记忆巩固过程可以在TBI患者中有效启动。然而，可能需要优化训练方案和时间表，以更好地激发这些患者的长期可塑性潜力。
