Behavioral and Neurophysiological Mechanisms of Interference in Skill Learning

技能学习干扰的行为和神经生理机制

• 批准号: 8325820
• 负责人: Gabriela Lucila Cantarero
• 金额: $ 2.91万
• 依托单位: JOHNS HOPKINS UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2011
• 资助国家: 美国
• 起止时间: 2011-07-26 至 2013-03-14
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8325820
• 关键词: Animals; Behavioral; Brain; Characteristics; Clinical; Exercise; Functional disorder; Goals; Hour; Human; Individual; Intervention; Investigation; Isometric Exercise; Lead; Learning; Lesion; Long-Term Depression; Long-Term Potentiation; Motor; Motor Cortex; Motor Skills; Patients; Performance; Rehabilitation therapy; Research; Resistance; Stroke; Techniques; Testing; Time; Training; Transcranial magnetic stimulation; Visual; Work; improved; motor learning; neurophysiology; prevent; relating to nervous system; resilience; restoration; skills; time interval

DESCRIPTION (provided by applicant): The goal of this project is to gain a better understanding of the neurophysiological substrates underlying interference of skill learning. Practicing motor tasks in close succession can interfere with learning, however, if sufficient time passes between the training of 2 skills (i.e. 6hrs), then interference is weaker. Despite extensive study about the behavioral consequences of interference, the neurophysiologic mechanisms underlying it are largely unknown. This is very important because the cortical plasticity changes associated with motor learning may represent the neurophysiological mechanisms that prevent learning of a second task. For instance, animal studies have shown motor learning induced long-term potentiation (LTP) changes in the trained primary motor cortex are also associated with a reduced capacity to sustain more LTP, a phenomenon known as LTP-saturation or homeostatic plasticity. Homeostatic plasticity has also been observed in humans. The overall purpose of this proposal is to test whether homeostatic plasticity following skill learning is one of the mechanisms underlying behavioral interference. This will be accomplished by using non-invasive transcranial direct current stimulation (tDCS) to induce LTP-like plasticity changes after training of a sequential visual isometric pinch task (SVIPT) either in the context of learning, performance with no learning, or learning with interference. To determine excitability changes in the motor cortex resulting from training and tDCS, transcranial magnetic stimulation (TMS) will be used to assess the magnitude of saturation (homeostatic plasticity) associated with practicing the task in these contexts. In Aim 1, I hypothesize that the acquisition of a skill will result in the saturation of the LTP-like plasticity effects of anodal tDCS (homeostatic plasticity phenomena), and that the magnitude of this homeostatic plasticity after learning a skill will be proportional to the magnitude of retention and interference. In addition, I will assess the effect of time on the neurophysiology of interference. In Aim 2, I hypothesize that 6 hours of time between training of 2 skills will be associated with a restoration of the LTP-like plasticity of anodal tDCS (lack of saturation), and that this restoration will be associated with a decrease in interference. These results would indicate that LTP-like changes in the primary motor cortex resulting from learning are at least one of the neural substrates underlying behavioral interference. If this holds true the homeostatic plasticity phenomena can become a predictor of interference. Importantly, improving our understanding of the basic mechanisms underlying skill learning and interference has clear clinical benefits. These findings have the potential to impact how individuals train motor skills, and perhaps more importantly, how rehabilitation training exercises are delivered in patients after brain lesions like stroke. Furthermore, this research may prove useful to develop interventions to enhance learning of multiple tasks.

描述（由申请人提供）： 这个项目的目标是获得一个更好的理解的神经生理学基板的干扰技能学习。连续练习运动任务可能会干扰学习，但是，如果在两种技能的训练之间有足够的时间（即6小时），那么干扰就会减弱。尽管对干扰的行为后果进行了广泛的研究，但其背后的神经生理机制在很大程度上是未知的。这非常重要，因为与运动学习相关的皮质可塑性变化可能代表了阻止学习第二项任务的神经生理机制。例如，动物研究表明，运动学习诱导的长时程增强（LTP）在训练的初级运动皮层的变化也与降低的能力，以维持更多的LTP，一种现象称为LTP饱和或稳态可塑性。在人类中也观察到了稳态可塑性。这个提议的总体目的是测试技能学习后的稳态可塑性是否是行为干扰的机制之一。这将通过使用非侵入性经颅直流电刺激（tDCS）来完成，以诱导LTP样可塑性变化后，训练的顺序视觉等长捏任务（SVIPT）无论是在学习的背景下，性能没有学习，或学习干扰。为了确定由训练和tDCS引起的运动皮层的兴奋性变化，将使用经颅磁刺激（TMS）来评估与在这些背景下练习任务相关的饱和度（稳态可塑性）。在目标1中，我假设获得一项技能将导致LTP样的可塑性效应的阳极tDCS（稳态可塑性现象）的饱和，并且学习技能后这种稳态可塑性的大小将与保留和干扰的大小成比例。此外，我将评估时间对干扰的神经生理学的影响。在目标2中，我假设两种技能训练之间的6小时时间将与阳极tDCS的LTP样可塑性（缺乏饱和度）的恢复相关，并且这种恢复将与干扰的减少相关。这些结果表明，LTP样的变化，在初级运动皮层导致学习至少是一个神经基板的行为干扰。如果这是真的，那么内稳态可塑性现象就可以成为干扰的预测因子。重要的是，提高我们对技能学习和干预的基本机制的理解具有明显的临床益处。这些发现有可能影响个人如何训练运动技能，也许更重要的是，如何在中风等脑损伤后为患者提供康复训练。此外，这项研究可能有助于开发干预措施，以提高多任务的学习。