FMRIB Centre, Wellcome Centre for Integrative Neuroimaging, Oxford, UK; Nuffield Division of Anesthetics, Nuffield Department of Clinical Neurosciences, University of Oxford, Oxford, UK; Department of Physiology, Anatomy and Genetics, University of Oxford, Oxford, UK.
Department of Physiology, Anatomy and Genetics, University of Oxford, Oxford, UK.
Neuroimage. 2018 Oct 1;179:92-101. doi: 10.1016/j.neuroimage.2018.06.021. Epub 2018 Jun 8.
Athletes regularly endure large increases in ventilation and accompanying perceptions of breathlessness. Whilst breathing perceptions often correlate poorly with objective measures of lung function in both healthy and clinical populations, we have previously demonstrated closer matching between subjective breathlessness and changes in ventilation in endurance athletes, suggesting that athletes may be more accurate during respiratory interoception. To better understand the link between exercise and breathlessness, we sought to identify the mechanisms by which the brain processing of respiratory perception might be optimised in athletes. Twenty endurance athletes and twenty sedentary controls underwent 7 T functional magnetic resonance imaging. Inspiratory resistive loading induced conscious breathing perceptions (breathlessness), and a delay-conditioning paradigm was employed to evoke preceding periods of breathlessness-anticipation. Athletes demonstrated anticipatory brain activity that positively correlated with resulting breathing perceptions within key interoceptive areas, such as the thalamus, insula and primary sensorimotor cortices, which was negatively correlated in sedentary controls. Athletes also exhibited altered connectivity between interoceptive attention networks and primary sensorimotor cortex. These functional differences in athletic brains suggest that exercise may alter anticipatory representations of respiratory sensations. Future work may probe whether these brain mechanisms are harnessed when exercise is employed to treat breathlessness within chronic respiratory disease.
运动员经常承受通气量的大幅增加和随之而来的呼吸困难感。虽然在健康人群和临床人群中，呼吸感知通常与肺功能的客观测量相关性较差，但我们之前已经证明，耐力运动员的主观呼吸困难感与通气量的变化更为匹配，这表明运动员在呼吸内感受方面可能更准确。为了更好地理解运动与呼吸困难之间的联系，我们试图确定大脑处理呼吸感知的机制如何在运动员中得到优化。二十名耐力运动员和二十名久坐不动的对照组接受了 7T 功能磁共振成像。吸气阻力加载会引起有意识的呼吸感知（呼吸困难），并采用延迟 Conditioning 范式来诱发先前的呼吸困难预期期。运动员表现出与关键的内脏感知区域（如丘脑、脑岛和初级感觉运动皮层）内的呼吸感知结果呈正相关的预期大脑活动，而久坐不动的对照组则呈负相关。运动员的内脏感知注意网络和初级感觉运动皮层之间的连通性也发生了改变。这些运动员大脑的功能差异表明，运动可能改变对呼吸感觉的预期表现。未来的研究可能会探究在慢性呼吸系统疾病中，运动被用于治疗呼吸困难时，这些大脑机制是否被利用。
