Nes, Lise Solberg, Ehlers, Shawna L, Whipple, Mary O et al. · Journal of pain research · 2013 · DOI
This study created a new questionnaire to measure a specific type of mental tiredness called self-regulatory fatigue—the exhaustion that comes from having to constantly manage your thoughts, emotions, and behaviors. Researchers gave this 18-question test to nearly 300 people with chronic illnesses like fibromyalgia and ME/CFS, along with standard fatigue and self-control tests. They found that this mental tiredness is related to, but distinct from, physical fatigue—suggesting it's a separate problem worth measuring and understanding.
ME/CFS patients often report severe cognitive and emotional difficulties alongside physical fatigue, yet these mental regulatory challenges are poorly characterized in clinical practice. This study proposes a validated instrument to separately measure self-regulatory fatigue from physical fatigue, potentially helping clinicians and researchers better understand and address the cognitive-emotional burden of ME/CFS and similar conditions.
This study does not prove that self-regulatory fatigue causes physical fatigue or vice versa—the strong correlation (r = 0.75) suggests they co-occur but does not establish causality. The cross-sectional design means we cannot determine whether self-regulatory problems precede or result from chronic illness. Additionally, the scale's validation is preliminary and requires replication in independent samples before clinical adoption.
About the PEM badge: “PEM required” means post-exertional malaise was an explicit required diagnostic criterion for participant inclusion in this study — not that PEM was studied, observed, or discussed. Studies using criteria that do not require PEM (e.g. Fukuda, Oxford) are tagged “PEM not required”. How the atlas works →
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