title: Resting-state synchrony between the retrosplenial cortex and anterior medial cortical structures relates to memory complaints in subjective cognitive impairment.
abstract: Subjective cognitive impairment (SCI) is a clinical state characterized by subjective cognitive deficits without cognitive impairment. To test the hypothesis that this state might involve dysfunction of self-referential processing mediated by cortical midline structures, we investigated abnormalities of functional connectivity in these structures in individuals with SCI using resting-state functional magnetic resonance imaging. We performed functional connectivity analysis for 23 individuals with SCI and 30 individuals without SCI. To reveal the pathophysiological basis of the functional connectivity change, we performed magnetic resonance-diffusion tensor imaging. Positron emission tomography-amyloid imaging was conducted in 13 SCI and 15 nonSCI subjects. Individuals with SCI showed reduced functional connectivity in cortical midline structures. Reduction in white matter connections was related to reduced functional connectivity, but we found no amyloid deposition in individuals with SCI. The results do not necessarily contradict the possibility that SCI indicates initial cognitive decrements, but imply that reduced functional connectivity in cortical midline structures contributes to overestimation of the experience of forgetfulness.
authors: Department of Psychiatry, Nara Medical University, Kashihara, Japan; Department of Investigative Radiology, National Cerebral and Cardiovascular Center, Suita, Japan. Electronic address: ejm86rp@yahoo.co.jp.
authors: Fumihiko
authors: F
authors: Yasuno
authors: Department of Neuropsychiatry, Osaka University Medical School, Suita, Japan.
authors: Hiroaki
authors: H
authors: Kazui
authors: Department of Investigative Radiology, National Cerebral and Cardiovascular Center, Suita, Japan.
authors: Akihide
authors: A
authors: Yamamoto
authors: Department of Radiology, National Cerebral and Cardiovascular Center, Suita, Japan.
authors: Naomi
authors: N
authors: Morita
authors: Department of Neurology, National Cerebral and Cardiovascular Center, Suita, Japan.
authors: Katsufumi
authors: K
authors: Kajimoto
authors: Department of Neurology, National Cerebral and Cardiovascular Center, Suita, Japan.
authors: Masafumi
authors: M
authors: Ihara
authors: Department of Neurology, National Cerebral and Cardiovascular Center, Suita, Japan; Department of Regenerative Medicine Research, Institute of Biomedical Research and Innovation, Kobe, Japan.
authors: Akihiko
authors: A
authors: Taguchi
authors: Department of Psychiatry, Nara Medical University, Kashihara, Japan.
authors: Kiwamu
authors: K
authors: Matsuoka
authors: Department of Psychiatry, Nara Medical University, Kashihara, Japan.
authors: Jun
authors: J
authors: Kosaka
authors: Department of Neuropsychiatry, Osaka University Medical School, Suita, Japan.
authors: Toshihisa
authors: T
authors: Tanaka
authors: Department of Psychiatry, Osaka University Health Care Center, Suita, Japan.
authors: Takashi
authors: T
authors: Kudo
authors: Department of Neuropsychiatry, Osaka University Medical School, Suita, Japan.
authors: Masatoshi
authors: M
authors: Takeda
authors: Department of Neurology, National Cerebral and Cardiovascular Center, Suita, Japan.
authors: Kazuyuki
authors: K
authors: Nagatsuka
authors: Department of Radiology, National Cerebral and Cardiovascular Center, Suita, Japan.
authors: Hidehiro
authors: H
authors: Iida
authors: Department of Psychiatry, Nara Medical University, Kashihara, Japan.
authors: Toshifumi
authors: T
authors: Kishimoto
mesh_terms: D000368:Aged; D002540:Cerebral Cortex / Q000473:pathology* / Q000503:physiopathology*; D003072:Cognition Disorders / Q000473:pathology* / Q000503:physiopathology / Q000523:psychology*; D056324:Diffusion Tensor Imaging; D005260:Female; D006801:Humans; D008297:Male; D008568:Memory / Q000502:physiology*; D008875:Middle Aged; D012146:Rest / Q000502:physiology*; D066127:White Matter / Q000473:pathology / Q000503:physiopathology
keywords: Amyloid imaging; Cortical midline structures; Diffusion tensor imaging (DTI); Resting-state functional MRI (fMRI); Self-referential processing; Subjective cognitive impairment (SCI)