UMRS1158 Neurophysiologie Respiratoire Expérimentale et Clinique, Sorbonne Université, INSERM, 75005, Paris, France.
Arts et Metiers Institute of Technology, IBHGC, 151 bd de l'Hopital, 75013, Paris, France.
Eur J Appl Physiol. 2020 May;120(5):1063-1074. doi: 10.1007/s00421-020-04345-1. Epub 2020 Mar 17.
In healthy humans, postural and respiratory dynamics are intimately linked and a breathing-related postural perturbation is evident in joint kinematics. A cognitive dual-task paradigm that is known to induce both postural and ventilatory disturbances can be used to modulate this multijoint posturo-ventilatory (PV) interaction, particularly in the cervical spine, which supports the head. The objective of this study was to assess this modulation.
With the use of optoelectronic sensors, the breathing profile, articular joint motions of the cervical spine, hip, knees and ankles, and centre of pressure (CoP) displacement were measured in 20 healthy subjects (37 years old [29; 49], 10 females) during natural breathing (NB), a cognitive dual task (COG), and eyes-closed and increased-tidal-volume conditions. The PV interaction in the CoP and joint motions were evaluated by calculating the respiratory emergence (REm).
Only the COG condition induced a decrease in the cervical REm (NB: 17.2% [7.8; 37.2]; COG: 4.2% [1.8; 10.0] p = 0.0020) concurrent with no changes in the cervical motion. The CoP REm (NB: 6.2% [3.8; 10.3]; COG: 12.9% [5.8; 20.7] p = 0.0696) and breathing frequency (NB: 16.6 min-1 [13.3; 18.7]; COG: 18.6 min-1 [16.3; 19.4] p = 0.0731) tended to increase, while the CoP (p = 0.0072) and lower joint motion displacements (p < 0.05) increased.
This study shows stable cervical spine motion during a cognitive dual task, as well as increased postural perturbations globally and in other joints. The concurrent reduction in the PV interaction at the cervical spine suggests that this "stabilization strategy" is centrally controlled and is achieved by a reduction in the breathing-related postural perturbations at this level. Whether this strategy is a goal for maintaining balance remains to be studied.
在健康人群中，姿势和呼吸动力学密切相关，关节运动学中明显存在与呼吸相关的姿势扰动。一种已知会引起姿势和通气紊乱的认知双重任务范式可用于调节这种多关节姿势-通气（PV）相互作用，特别是在支撑头部的颈椎。本研究的目的是评估这种调节。
使用光电传感器，在 20 名健康受试者（37 岁 [29；49]，10 名女性）中测量自然呼吸（NB）、认知双重任务（COG）、闭眼和增加潮气量期间的呼吸模式、颈椎、髋关节、膝关节和踝关节的关节运动以及中心压力（CoP）位移。通过计算呼吸出现（REm）来评估 CoP 和关节运动中的 PV 相互作用。
只有 COG 条件会导致颈椎 REm 降低（NB：17.2%[7.8；37.2]；COG：4.2%[1.8；10.0]p=0.0020），同时颈椎运动无变化。CoP REm（NB：6.2%[3.8；10.3]；COG：12.9%[5.8；20.7]p=0.0696）和呼吸频率（NB：16.6 min-1[13.3；18.7]；COG：18.6 min-1[16.3；19.4]p=0.0731）趋于增加，而 CoP（p=0.0072）和较低关节运动位移（p<0.05）增加。
本研究表明，在认知双重任务期间颈椎运动稳定，全身和其他关节的姿势扰动增加。颈椎 PV 相互作用的同时减少表明这种“稳定策略”是由中枢控制的，并且通过减少该水平的呼吸相关姿势扰动来实现。这种策略是否是维持平衡的目标还有待研究。
