Abstract:
Chronic Fatigue Syndrome/Myalgic Encephalomyelitis (CFS/ME) is characterised by continuous fatigue and has many diagnostic criteria. Cognitive dysfunction affects 86-94% of adults with CFS/ME.
This thesis used MRI applications to investigate brain structure and function in CFS/ME. This thesis hypothesised to find brain volume differences, functional connectivity differences in brain networks, and functional differences measured by Blood Oxygenation Level Dependant (BOLD) signal activation during working memory task performance.
The working memory paradigm was designed to investigate working memory components, processing and storage separately and combined. The relationship between fatigue and performance was assessed. This thesis’s original contribution provides evidence that the salience network might have altered resting-state functional connectivity in CFS/ME in the absence of morphological differences.
The salience network is involved in detecting and integrating salient sensory information; therefore, disruption in this network might disrupt incoming cognitive stimuli and influence other networks’ connectivity, involved in fatigue and impaired memory.
In the more demanding task, participants with CFS/ME were slower and less accurate but used the same working memory network as healthy controls. No brain volume differences, nor atrophy were found. The differences between these findings compared to previous studies might be due to different study designs, analysis methods, sample sizes with different symptoms, including illness duration, physical inactivity and sleep disturbance.
The salience network alteration could potentially have a significant role in CFS/ME, as we cannot determine cause and effect with current experimental design the association with fatigue and other CFS/ME symptoms remains unclear. Using longitudinal studies that account for neurologically relevant confounders are needed in CFS/ME to further investigate the role of salience network.
Source: Almutairi, Basim S. Investigating the neural substrates of Chronic Fatigue Syndrome/Myalgic Encephalomyelitis (CFS/ME) : a structural and functional MRI study. PhD Thesis, University of Bristol. uk.bl.ethos.866683 https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.866683