title: Mammillothalamic functional connectivity and memory function in Wernicke's encephalopathy.
abstract: There is still debate over the neural mechanisms underlying pathogenic and even recovery processes of Wernicke's encephalopathy. Therefore, we attempted to validate the usefulness of resting-state functional connectivity analysis in assessing memory function and its neural correlation with the mammillothalamic tract in patients recovering from Wernicke's encephalopathy. Seven chronic alcoholics recovering from Wernicke's encephalopathy, 14 alcoholic comparisons without Wernicke's encephalopathy, and 14 healthy comparisons underwent functional connectivity MRI scans, as well as verbal and non-verbal memory tests after at least a 1 month abstinence from alcohol. Resting-state functional connectivity strength between the anterior thalamus and the mammillary bodies was investigated by calculating temporal correlations in magnetic resonance signal levels between the two regions during a 5-min passive viewing task. The mean values of the functional connectivity strength between the left anterior thalamus and the ipsilateral mammillary body differed significantly between Wernicke's encephalopathy patients and healthy comparisons (P = 0.014). This connectivity strength in alcoholic comparisons fell between those of the former two groups, with a significant difference from that of healthy comparisons (P = 0.038). In addition, the strength of this left-sided functional connectivity significantly correlated with delayed verbal recall scores (r = 0.771, P = 0.042) and verbal recognition score (r = 0.825, P = 0.022) in patients with Wernicke's encephalopathy. Our findings indicate that memory function in patients recovering from Wernicke's encephalopathy parallels the level of the mammillothalamic functional connectivity; this supports the usefulness of resting-state functional connectivity analysis as a practical alternative to pathological examination of the mammillothalamic tract in living patients with Wernicke's encephalopathy.
authors.affiliation: Institute of Behavioral Science in Medicine, Yonsei University College of Medicine, Seoul, Korea.
authors.forename: Eosu
authors.initials: E
authors.lastname: Kim
authors.forename: Jeonghun
authors.initials: J
authors.lastname: Ku
authors.forename: Kee
authors.initials: K
authors.lastname: Namkoong
authors.forename: Wonho
authors.initials: W
authors.lastname: Lee
authors.forename: Kang Soo
authors.initials: KS
authors.lastname: Lee
authors.forename: Ji-Yeon
authors.initials: JY
authors.lastname: Park
authors.forename: Su Young
authors.initials: SY
authors.lastname: Lee
authors.forename: Jae-Jin
authors.initials: JJ
authors.lastname: Kim
authors.forename: Sun I
authors.initials: SI
authors.lastname: Kim
authors.forename: Young-Chul
authors.initials: YC
authors.lastname: Jung
mesh_terms: D000328:Adult; D000437:Alcoholism / Q000473:pathology / Q000503:physiopathology; D020643:Anterior Thalamic Nuclei / Q000473:pathology / Q000503:physiopathology; D001921:Brain / Q000473:pathology / Q000503:physiopathology*; D016022:Case-Control Studies; D006801:Humans; D008279:Magnetic Resonance Imaging; D008326:Mammillary Bodies / Q000473:pathology / Q000503:physiopathology; D008568:Memory / Q000502:physiology*; D008875:Middle Aged; D009434:Neural Pathways / Q000502:physiology; D009483:Neuropsychological Tests; D013831:Thiamine / Q000627:therapeutic use; D014803:Vitamin B Complex / Q000627:therapeutic use; D014899:Wernicke Encephalopathy / Q000188:drug therapy / Q000473:pathology / Q000503:physiopathology*
chemical_list: D014803:Vitamin B Complex; D013831:Thiamine