J Sport Rehabil. 2019 Oct 18;29(4):441-447. doi: 10.1123/jsr.2018-0026. Print 2020 May 1.
Although the beneficial effects of using an external focus of attention are well documented in attainment and performance of movement execution, neural mechanisms underlying external focus' benefits are mostly unknown.
To assess brain function during a lower-extremity gross motor movement while manipulating an internal and external focus of attention.
Cross-over study.
Neuroimaging center Participants: A total of 10 healthy subjects (5 males and 5 females) Intervention: Participants completed external and internal focus of attention unilateral left 45° knee extension/flexion movements at a rate of 1.2 Hz laying supine in a magnetic resonance imaging scanner for 4 blocks of 30 seconds interspersed with 30-second rest blocks. During the internal condition, participants were instructed to "squeeze their quadriceps." During the external condition, participants were instructed to "focus on a target" positioned above their tibia.
T1 brain structural imaging was performed for registration of the functional data. For each condition, 3T functional magnetic resonance imaging blood oxygenation level dependent data representing 90 whole-brain volumes were acquired.
During the external relative to internal condition, increased activation was detected in the right occipital pole, cuneal cortex, anterior portion of the lingual gyrus, and intracalcarine cortex (Zmax = 4.5-6.2, P < .001). During the internal relative to external condition, increased activation was detected in the left primary motor cortex, left supplementary motor cortex, and cerebellum (Zmax = 3.4-3.5, P < .001).
Current results suggest that an external focus directed toward a visual target produces more brain activity in regions associated with vision and ventral streaming pathways, whereas an internal focus manipulated through instruction increases activation in brain regions that are responsible for motor control. Results from this study serve as baseline information for future prevention and rehabilitation investigations of how manipulating focus of attention can constructively affect neuroplasticity during training and rehabilitation.
虽然将注意力集中于外部对运动执行的习得和表现有有益影响已得到充分证实，但外部焦点益处的神经机制在很大程度上仍是未知的。
在进行下肢粗大运动时，评估在操纵内部和外部注意力焦点时的大脑功能。
交叉研究。
神经影像学中心
共有 10 名健康受试者（5 名男性和 5 名女性）
参与者在磁共振成像扫描仪中仰卧位，以 1.2 Hz 的速度完成外部和内部焦点的左膝 45°伸展/弯曲运动，每 30 秒完成 1 次，共 4 个 30 秒块，中间穿插 30 秒休息块。在内部条件下，参与者被指示“收缩股四头肌”。在外部条件下，参与者被指示“将注意力集中在定位在胫骨上方的目标上”。
进行 T1 脑结构成像以注册功能数据。对于每种条件，采集代表 90 个全脑容积的 3T 功能磁共振成像血氧水平依赖数据。
与内部条件相比，外部条件下右枕极、楔叶、舌回前部分和距状回内皮层（Zmax=4.5-6.2，P<0.001）的激活增加。与外部条件相比，内部条件下左初级运动皮层、左辅助运动皮层和小脑（Zmax=3.4-3.5，P<0.001）的激活增加。
目前的结果表明，指向视觉目标的外部焦点会在与视觉和腹侧流途径相关的区域产生更多的大脑活动，而通过指令操纵的内部焦点会增加负责运动控制的大脑区域的激活。本研究的结果为未来的注意力焦点调节如何在训练和康复过程中建设性地影响神经可塑性的预防和康复研究提供了基线信息。
