title: Altered Resting-State Cortical EEG Oscillations in Patients With Severe Asymptomatic Carotid Stenosis.
abstract: Asymptomatic carotid stenosis is characterized by altered cerebral hemodynamics and cognitive impairment, but the underlying neurophysiological mechanism remains unclear. To elucidate the alterations of cortical activities, resting-state electrophysiological activities were recorded from patients with mild (<30%; n=10; age 57-85 years), moderate (30% to 50%; n=11; age 66-88 years), and severe (>50%; n=8; age 67-91 years) carotid stenosis. The current density and oscillatory power of the cortical sources were analyzed using the minimum norm estimates method combined with fast Fourier transform analysis. Our results indicate that the cortical current density among regions of the brain was similar, irrespective of the degree of carotid stenosis. With regard to the cortical oscillations, augmented theta activities in the bilateral parietal, left temporal, and left occipital regions and attenuated alpha activities in the bilateral frontal and right central regions were obtained in patients with severe asymptomatic carotid stenosis. We suggest that the source-based cortical oscillations at theta and alpha bands might reflect the alterations of the brain activities and characterize the altered neurophysiological mechanism of the brain with at least 50% occlusion of the carotid artery. Further longitudinal studies with larger populations are warranted to verify the present findings.
authors.affiliation: Brain Research Center, National Yang-Ming University, Taipei, Taiwan Institute of Brain Science, National Yang-Ming University, Taipei, Taiwan Department of Education and Research, Taipei City Hospital, Taipei, Taiwan Department of Neurology, Taipei City Hospital, Taipei, Taiwan Laboratory of Neurophysiology, Department of Medical Research and Education, Taipei Veterans General Hospital, Taipei, Taiwan fujunghsiao@gmail.com yylin@vghtpe.gov.tw.
authors.forename: Fu-Jung
authors.initials: FJ
authors.lastname: Hsiao
authors.affiliation: Department of Education and Research, Taipei City Hospital, Taipei, Taiwan.
authors.forename: Fang-Yuh
authors.initials: FY
authors.lastname: Hsieh
authors.affiliation: Brain Research Center, National Yang-Ming University, Taipei, Taiwan Institute of Brain Science, National Yang-Ming University, Taipei, Taiwan Department of Neurosurgery, Taipei City Hospital, Taipei, Taiwan Laboratory of Neurophysiology, Department of Medical Research and Education, Taipei Veterans General Hospital, Taipei, Taiwan.
authors.forename: Wei-Ta
authors.initials: WT
authors.lastname: Chen
authors.affiliation: Department of Neurology, Taipei Veterans General Hospital, Taipei, Taiwan.
authors.forename: Da-Chen
authors.initials: DC
authors.lastname: Chu
authors.affiliation: Brain Research Center, National Yang-Ming University, Taipei, Taiwan Institute of Brain Science, National Yang-Ming University, Taipei, Taiwan Department of Neurology, Taipei City Hospital, Taipei, Taiwan Department of Neurosurgery, Taipei City Hospital, Taipei, Taiwan Laboratory of Neurophysiology, Department of Medical Research and Education, Taipei Veterans General Hospital, Taipei, Taiwan.
authors.forename: Yung-Yang
authors.initials: YY
authors.lastname: Lin
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D058070:Asymptomatic Diseases; D058256:Brain Waves / Q000502:physiology*; D016893:Carotid Stenosis / Q000150:complications / Q000000981:diagnostic imaging / Q000503:physiopathology*; D002540:Cerebral Cortex / Q000098:blood supply / Q000503:physiopathology*; D003072:Cognition Disorders / Q000209:etiology / Q000503:physiopathology*; D004569:Electroencephalography; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D012720:Severity of Illness Index; D014463:Ultrasonography
keywords: asymptomatic carotid stenosis (ACS); electroencephalography (EEG); minimum norm estimates (MNE); resting state; spectral power