The neural mechanisms of re-experiencing mental fatigue sensation: a magnetoencephalography study

PLoS One. 2015 Mar 31;10(3):e0122455. doi: 10.1371/journal.pone.0122455. eCollection 2015.

Abstract

There have been several studies which have tried to clarify the neural mechanisms of fatigue sensation; however fatigue sensation has multiple aspects. We hypothesized that past experience related to fatigue sensation is an important factor which contributes to future formation of fatigue sensation through the transfer to memories that are located within specific brain structures. Therefore, we aimed to investigate the neural mechanisms of fatigue sensation related to memory. In the present study, we investigated the neural activity caused by re-experiencing the fatigue sensation that had been experienced during a fatigue-inducing session. Thirteen healthy volunteers participated in fatigue and non-fatigue experiments in a crossover fashion. In the fatigue experiment, they performed a 2-back test session for 40 min to induce fatigue sensation, a rest session for 15 min to recover from fatigue, and a magnetoencephalography (MEG) session in which they were asked to re-experience the state of their body with fatigue that they had experienced in the 2-back test session. In the non-fatigue experiment, the participants performed a free session for 15 min, a rest session for 15 min, and an MEG session in which they were asked to re-experience the state of their body without fatigue that they had experienced in the free session. Spatial filtering analyses of oscillatory brain activity showed that the delta band power in the left Brodmann's area (BA) 39, alpha band power in the right pulvinar nucleus and the left BA 40, and beta band power in the left BA 40 were lower when they re-experienced the fatigue sensation than when they re-experienced the fatigue-free sensation, indicating that these brain regions are related to re-experiencing the fatigue sensation. Our findings may help clarify the neural mechanisms underlying fatigue sensation.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adolescent
  • Adult
  • Healthy Volunteers
  • Humans
  • Magnetoencephalography*
  • Male
  • Mental Fatigue / physiopathology*
  • Task Performance and Analysis

Grants and funding

This work was supported by a Grant-in-Aid for Young Scientists (B) (KAKENHI: 25750351) from the Ministry of Education, Culture, Sports, Science and Technology (MEXT) of Japan, the Health Labour Science Research Grant of Japan, and by a grant from the Ministry of Health, Labour and Welfare of Japan (URLs: http://www.jsps.go.jp/j-grantsinaid/index.html; http://www.mhlw.go.jp/stf/seisakunitsuite/bunya/hokabunya/kenkyujigyou/index.html). The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.