Gaoua Nadia, Herrera Christopher P, Périard Julien D, El Massioui Farid, Racinais Sebastien
School of Applied Sciences, London South Bank University, London, United Kingdom.
Athlete Health and Performance Research Centre, Aspetar Orthopaedic and Sports Medicine Hospital, Doha, Qatar.
Front Psychol. 2018 Jan 11;8:2290. doi: 10.3389/fpsyg.2017.02290. eCollection 2017.
The aim of this study was to verify the hypothesis that hyperthermia represents a cognitive load limiting available resources for executing concurrent cognitive tasks. Electroencephalographic activity (EEG: alpha and theta power) was obtained in 10 hyperthermic participants in HOT (50°C, 50% RH) conditions and in a normothermic state in CON (25°C, 50% RH) conditions in counterbalanced order. In each trial, EEG was measured over the frontal lobe prior to task engagement (PRE) in each condition and during simple (One Touch Stockings of Cambridge, OTS-4) and complex (OTS-6) cognitive tasks. Core (39.5 ± 0.5 vs. 36.9 ± 0.2°C) and mean skin (39.06 ± 0.3 vs. 31.6 ± 0.6°C) temperatures were significantly higher in HOT than CON ( < 0.005). Theta power significantly increased with task demand ( = 0.017, η = 0.36) and was significantly higher in HOT than CON ( = 0.041, η = 0.39). The difference between HOT and CON was large (η = 0.40) and significant ( = 0.036) PRE, large (η = 0.20) but not significant ( = 0.17) during OTS-4, and disappeared during OTS-6 ( = 0.87, η = 0.00). Those changes in theta power suggest that hyperthermia may act as an additional cognitive load. However, this load disappeared during OTS-6 together with an impaired performance, suggesting a potential saturation of the available resources.
体温过高会形成一种认知负荷，限制执行并发认知任务时可用的资源。对10名参与者进行了脑电图活动（EEG：α波和θ波功率）测量，参与者在热环境（50°C，50%相对湿度）下处于体温过高状态，在对照环境（25°C，50%相对湿度）下处于正常体温状态，两种状态以平衡顺序交替进行。在每次试验中，在每种状态下任务开始前（PRE）以及简单（剑桥单触式长袜测试，OTS - 4）和复杂（OTS - 6）认知任务期间，均对额叶进行脑电图测量。热环境下的核心体温（39.5±0.5 vs. 36.9±0.2°C）和平均皮肤温度（39.06±0.3 vs. 31.6±0.6°C）显著高于对照环境（<0.005）。θ波功率随任务需求显著增加（=0.017，η = 0.36），且热环境下显著高于对照环境（=0.041，η = 0.39）。热环境与对照环境之间的差异在PRE时较大（η = 0.40）且显著（=0.036），在OTS - 4期间较大（η = 0.20）但不显著（=0.17），在OTS - 6期间差异消失（=0.87，η = 0.00）。θ波功率的这些变化表明，体温过高可能会增加额外的认知负荷。然而，这种负荷在OTS - 6期间随着表现受损而消失，这表明可用资源可能已达到饱和。
