Department of Mechanical Engineering, University of British Columbia, 6250 Applied Science Ln Room 2054, Vancouver, BC, V6T 1Z4, Canada.
School of Biomedical Engineering, The University of British Columbia, 2222 Health Sciences Mall, Vancouver, BC, V6T 2B9, Canada.
Ann Biomed Eng. 2024 Oct;52(10):2897-2910. doi: 10.1007/s10439-024-03602-0. Epub 2024 Aug 13.
Athletes in contact and collision sports can sustain frequent subconcussive head impacts. Although most impacts exhibit low kinematics around or below 10 g of head linear acceleration, there is growing concern regarding the cumulative effects of repetitive sports head impacts. Even mild impacts can lead to brain deformations as shown through neuroimaging and finite element modeling, and thus may result in mild and transient effects on the brain, prompting further investigations of the biomechanical dose-brain response relationship. Here we report findings from a novel laboratory study with continuous monitoring of brain activity through electroencephalography (EEG) during controlled soccer head impacts. Eight healthy participants performed simulated soccer headers at 2 mild levels (6 g, 4 rad/s and 10 g, 8 rad/s) and three directions (frontal, oblique left, oblique right). Participants were instrumented with an inertial measurement unit (IMU) bite bar and EEG electrodes for synchronized head kinematics and brain activity measurements throughout the experiment. After an impact, EEG exhibited statistically significant elevation of relative and absolute delta power that recovered within two seconds from the impact moment. These changes were statistically significantly higher for 10 g impacts compared with 6 g impacts in some topographical regions, and oblique impacts resulted in contralateral delta power increases. Post-session resting state measurements did not indicate any cumulative effects. Our findings suggest that even mild soccer head impacts could lead to immediate, transient neurophysiological changes. This study paves the way for further dose-response studies to investigate the cumulative effects of mild sports head impacts, with implications for long-term athlete brain health.
接触性和碰撞性运动的运动员可能会频繁受到亚脑震荡性头部冲击。虽然大多数冲击的运动学特征显示头部线性加速度在 10g 左右或低于 10g，但人们越来越关注重复性运动性头部冲击的累积效应。即使是轻微的冲击也会导致大脑变形，这可以通过神经影像学和有限元建模来证明，因此可能会对大脑产生轻微和短暂的影响，从而促使进一步研究生物力学剂量-大脑反应关系。在这里，我们报告了一项新的实验室研究结果，该研究通过在受控的足球头部冲击过程中通过脑电图（EEG）进行连续监测来研究大脑活动。八名健康参与者以两种温和的强度（6g，4rad/s 和 10g，8rad/s）和三个方向（正面、左侧斜向、右侧斜向）进行模拟足球顶球。参与者配备了惯性测量单元（IMU）咬棒和 EEG 电极，用于在整个实验过程中同步测量头部运动学和大脑活动。冲击后，EEG 显示相对和绝对 delta 功率明显升高，从冲击时刻开始两秒钟内恢复。在某些拓扑区域，10g 冲击的这些变化明显高于 6g 冲击，并且斜向冲击导致对侧 delta 功率增加。会话后静息状态测量没有显示出任何累积效应。我们的研究结果表明，即使是温和的足球头部冲击也可能导致即时、短暂的神经生理变化。这项研究为进一步的剂量-反应研究铺平了道路，以研究轻度运动性头部冲击的累积效应，这对运动员的大脑健康具有长期影响。
