A new finding may link Chronic Fatigue Syndrome to the AIDS epidemic: Intra brainstem connectivity is impaired.
Intra brainstem connectivity is impaired in chronic fatigue syndrome
Neuroimage Clin. 2019 Oct 19;24:102045. doi:
10.1016/j.nicl.2019.102045. [Epub ahead of print]
Intra brainstem connectivity is impaired in chronic fatigue syndrome.
Barnden LR, Shan ZY, Staines DR, Marshall-Gradisnik S, Finegan K,
Ireland T, Bhuta S.
Abstract
In myalgic encephalomyelitis or chronic fatigue syndrome (ME/CFS),
abnormal MRI correlations with symptom severity and autonomic measures
have suggested impaired nerve signal conduction within the brainstem.
Here we analyse fMRI correlations to directly test connectivity within
and from the brainstem. Resting and task functional MRI (fMRI) were
acquired for 45 ME/CFS (Fukuda criteria) and 27 healthy controls (HC).
We selected limited brainstem reticular activation system (RAS)
regions-of-interest (ROIs) based on previous structural MRI findings
in a different ME/CFS cohort (bilateral rostral medulla and midbrain
cuneiform nucleus), the dorsal Raphe nucleus, and two subcortical ROIs
(hippocampus subiculum and thalamus intralaminar nucleus) reported to
have rich brainstem connections. When HC and ME/CFS were analysed
separately, significant correlations were detected for both groups
during both rest and task, with stronger correlations during task than
rest. In ME/CFS, connections were absent between medulla and midbrain
nuclei, although hippocampal connections with these nuclei were
enhanced. When corresponding correlations from HC and ME/CFS were
compared, ME/CFS connectivity deficits were detected within the
brainstem between the medulla and cuneiform nucleus and between the
brainstem and hippocampus and intralaminar thalamus, but only during
task. In CFS/ME, weaker connectivity between some RAS nuclei was
associated with increased symptom severity. RAS neuron oscillatory
signals facilitate coherence in thalamo-cortical oscillations.
Brainstem RAS connectivity deficits can explain autonomic changes and
diminish cortical oscillatory coherence which can impair attention,
memory, cognitive function, sleep quality and muscle tone, all
symptoms of ME/CFS.
Structural and functional brain imaging in acute HIV
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6082997/