Fatigue

=== Reduced brain connectivity ===
Fatigue has been correlated with reductions in structural and functional connectivity in the brain.<ref name="Qi-2019">{{Cite journal|title=Neural Mechanisms of Mental Fatigue Revisited: New Insights from the Brain Connectome|first1=Peng|last1=Qi|first2=Hua|last2=Ru|first3=Lingyun|last3=Gao|first4=Xiaobing|last4=Zhang|first5=Tianshu|last5=Zhou|first6=Yu|last6=Tian|first7=Nitish|last7=Thakor|first8=Anastasios|last8=Bezerianos|first9=Jinsong|last9=Li|first10=Yu|last10=Sun|date=April 1, 2019|journal=Engineering|volume=5|issue=2|pages=276–286|doi=10.1016/j.eng.2018.11.025|doi-access=free|bibcode=2019Engin...5..276Q }}</ref> This has included in post-stroke,<ref>{{Cite journal|title=Disruptions in Structural and Functional Connectivity Relate to Poststroke Fatigue|first1=Judith D.|last1=Schaechter|first2=Minhae|last2=Kim|first3=Baileigh G.|last3=Hightower|first4=Trevor|last4=Ragas|first5=Marco L.|last5=Loggia|date=February 28, 2023|journal=Brain Connectivity|volume=13|issue=1|pages=15–27|doi=10.1089/brain.2022.0021|pmid=35570655|pmc=9942175}}</ref> MS,<ref>{{Cite journal|title=Regional Brain Atrophy and Functional Connectivity Changes Related to Fatigue in Multiple Sclerosis|first1=Álvaro Javier|last1=Cruz Gómez|first2=Noelia|last2=Ventura Campos|first3=Antonio|last3=Belenguer|first4=César|last4=Ávila|first5=Cristina|last5=Forn|date=October 22, 2013|journal=PLOS ONE|volume=8|issue=10|pages=e77914|doi=10.1371/journal.pone.0077914|doi-access=free |pmid=24167590|pmc=3805520|bibcode=2013PLoSO...877914C }}</ref> NMOSD and MOG,<ref name="pmid37180990"/> and ME/CFS.<ref>{{Cite journal|title=Abnormal Resting-State Functional Connectivity in Patients with Chronic Fatigue Syndrome: Results of Seed and Data-Driven Analyses|first1=Charles W.|last1=Gay|first2=Michael E.|last2=Robinson|first3=Song|last3=Lai|first4=Andrew|last4=O'Shea|first5=Jason G.|last5=Craggs|first6=Donald D.|last6=Price|first7=Roland|last7=Staud|date=February 1, 2016|journal=Brain Connectivity|volume=6|issue=1|pages=48–56|doi=10.1089/brain.2015.0366|pmid=26449441|pmc=4744887}}</ref> This was also found for fatigue after brain injury,<ref name="pmid35221951">{{Cite journal|title=Cingulo-Opercular and Frontoparietal Network Control of Effort and Fatigue in Mild Traumatic Brain Injury|first1=Amy E.|last1=Ramage|first2=Kimberly L.|last2=Ray|first3=Hannah M.|last3=Franz|first4=David F.|last4=Tate|first5=Jeffrey D.|last5=Lewis|first6=Donald A.|last6=Robin|date=January 30, 2021|journal=Frontiers in Human Neuroscience|volume=15|doi=10.3389/fnhum.2021.788091|doi-access=free |pmid=35221951|pmc=8866657 }}</ref> including a significant linear correlation between self-reported fatigue and brain functional connectivity.<ref name="pmid26878885">{{Cite journal|title=Post mTBI fatigue is associated with abnormal brain functional connectivity|first1=Love Engström|last1=Nordin|first2=Marika Christina|last2=Möller|first3=Per|last3=Julin|first4=Aniko|last4=Bartfai|first5=Farouk|last5=Hashim|first6=Tie-Qiang|last6=Li|date=February 16, 2016|journal=Scientific Reports|volume=6|issue=1|page=21183|doi=10.1038/srep21183|pmid=26878885 |pmc=4754765 |bibcode=2016NatSR...621183N }}</ref>

Areas of the brain for which there is evidence of relation to fatigue are the thalamus and middle frontal cortex,<ref name="pmid26878885" /> fronto-parietal and cingulo-opercular,<ref name="pmid35221951" />  and default mode network, salience network, and thalamocortical loop areas.<ref name="Qi-2019" /><ref>{{cite journal |last1=Borghetti |first1=Lorraine |last2=Rhodes |first2=L. Jack |last3=Morris |first3=Megan B. |title=Fatigue Leads to Dynamic Shift in Fronto-parietal Sustained Attention Network |journal=Proceedings of the Human Factors and Ergonomics Society Annual Meeting |date=September 2022 |volume=66 |issue=1 |pages=606–610 |doi=10.1177/1071181322661056 |s2cid=253205546 }}</ref>