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Published on: June 18, 2021
Increased Frontal Lobe Activation After Aneurysmal Subarachnoid Hemorrhage
Leodante da Costa1, Benjamin T Dunkley2, Allison Bethune2
1From the Department of Surgery, Division of Neurosurgery, Sunnybrook Health Sciences Centre (L.d.C., A.B.), Department of Medical Imaging, Sunnybrook Health Sciences Centre (L.d.C.), Department of Diagnostic Imaging, The Hospital for Sick Children (B.T.D., A.R.), and Division of Neurology, The Hospital for Sick Children (A.K., E.W.P.), University of Toronto, Ontario, Canada. leo.dacosta@sunnybrook.ca.
Magnetoencephalography revealed altered brain activation in aneurysmal subarachnoid hemorrhage survivors, linking anterior cingulate cortex connectivity to cognitive deficits. These neurophysiological changes may explain common neurocognitive issues post-treatment.
Area of Science:
- Neuroscience
- Cognitive Neurology
- Neuroimaging
Background:
- Neurocognitive deficits are prevalent in aneurysmal subarachnoid hemorrhage (aSAH) survivors, even without structural lesions.
- Understanding the neurophysiological basis of these deficits is crucial for improving patient outcomes.
Purpose of the Study:
- To investigate the neurophysiological underpinnings of cognitive dysfunction in aSAH patients using magnetoencephalography (MEG).
- To identify neural correlates of cognitive deficits in aSAH survivors.
Main Methods:
- Thirteen aSAH patients treated with coiling and 13 matched controls underwent neuropsychological testing and MEG.
- MEG data acquired during resting state and cognitive tasks (go-no-go, set-shifting).
- Mean time from treatment to testing was 18.8 months.
Main Results:
- aSAH patients showed greater activation in the right anterior cingulate and inferior frontal gyrus during inhibition tasks.
- Increased activity in bilateral anterior cingulate cortex and right medial frontal gyrus observed during set-shifting tasks.
- Negative correlation found between resting-state beta-band anterior cingulate connectivity and Montreal Cognitive Assessment scores, indicating poorer performance with higher connectivity.
Conclusions:
- Increased activation in the anterior cingulate gyrus and frontobasal regions during demanding tasks in good-grade aSAH patients.
- Negative correlation between anterior cingulate gyrus activation and cognitive scores suggests a link to neurocognitive complaints.
- Subtle neurophysiological differences identified may explain common neurocognitive and behavioral issues in aSAH survivors.
