Master of Science
Measures of mental fatigue often do not consider daily life experiences, and existing measures fail to distinguish among various, potentially dissociable, ways that mental fatigue manifests. The present studies assessed the validity of the newly created Experiential Impact of Mental Fatigue Scale (EIMFS). Participants (Study 1, n = 365; Study 2, n = 243) responded to 85 items that address the various forms of mental fatigue across different situational contexts. The final scale, analysed through both exploratory and confirmatory factor analysis, included 22 items that loaded differentially on four factors which I term: emotional consequences, daily life impact, cognitive difficulties, and motivation and engagement. Each of the four subfactors as well as the scale overall had acceptable reliability and demonstrated construct and criterion validity with ancillary measures. Future research should administer the EIMFS in various neuropsychological populations to explore the relationship between mental fatigue and other symptoms experienced by these groups.
Summary for Lay Audience
Fatigue, including mental fatigue affects all aspects of cognition and emotion, with potentially devastating effects on quality of life. The onset may begin after engaging in intense or demanding cognitive experiences. It can result in difficulties making decisions, negative effects on mood, poor task performance, and reduced productivity. And yet, mental fatigue remains relatively unexplored as a construct, since it is difficult to define and measure. Assessment of mental fatigue should include how it affects people in their daily life. This would include examining contextual factors that exacerbate feelings of mental fatigue.
Although numerous mental fatigue scales exist, these measures often fail to assess how mental fatigue manifests in daily life experiences. Thus, I present a new scale to address mental fatigue – The Experiential Impact of Mental Fatigue Scale (EIMFS). This self-report measure assesses individuals’ experiences of mental fatigue and impact it has on their life. The experiential impact of mental fatigue is characterized as a psychological condition that has both subjective and objective aspects. Subjectively it can be defined as the perception of being involuntarily unable to complete mental tasks. Objectively it influences an individual’s ability to focus, withstand distraction, and/or initiate and sustain motivation. The EIMFS includes 88 questions (three attention checks and 85 “true” items) that address the various forms of mental fatigue across different situational contexts.
Data were collected from two samples (Study 1 included 365 participants and Study 2 included 243 participants). Participants completed the EIMFS by rating the extent to which each of the items applied to them right now. The final scale included 22 of the original 85 items.
The results from this study suggest that the EIMFS has good reliability and validity. Results support the prediction that mental fatigue is multidimensional, and the EIMFS includes four subscales which I term: emotional consequences, daily life impact, cognitive difficulties, and motivation and engagement.
Richards, Olivia H., "The Development of the Experiential Impact of Mental Fatigue Scale" (2023). Electronic Thesis and Dissertation Repository. 9644.