脳梗塞における機能的結合MRI： エビデンスに基づく臨床的レビュー

Functional connectivity magnetic resonance imaging in stroke: an evidence-based clinical review.
Int J Stroke. 2013 Mar 19;
Authors: Varsou O, Macleod MJ, Schwarzbauer C

れびゅー。

アクセス可能な文化マインドセットはデフォルトモードの活動を調整する： 文化的に位置づけられた脳における知見

Accessible cultural mind-set modulates default mode activity: Evidence for the culturally situated brain.
Soc Neurosci. 2013 Mar 13;
Authors: Wang C, Oyserman D, Liu Q, Li H, Han S

ちょくやくあんどちょくやく。
あぶすと読む気力なす。

集中的な推論訓練は安静時の脳結合パターンを変える

Intensive reasoning training alters patterns of brain connectivity at rest.
J Neurosci. 2013 Mar 13;33(11):4796-803
Authors: Mackey AP, Miller Singley AT, Bunge SA

たいとーのみ

認知的不満と健忘性軽度認知障害をもつ高齢者におけるデフォルトモードネットワークの変化

Altered Default Mode Network Connectivity in Older Adults with Cognitive Complaints and Amnestic Mild Cognitive Impairment.
J Alzheimers Dis. 2013 Mar 12;
Authors: Wang Y, Risacher SL, West JD, McDonald BC, Magee TR, Farlow MR, Gao S, O'Neill DP, Saykin AJ

Default mode network (DMN) disruption has been reported in Alzheimer's disease (AD), yet the specific pattern of altered connectivity over the course of prodromal AD remains to be characterized. The aim of this study was to assess DMN connectivity in older adults with informant-verified cognitive complaints (CC) but normal neuropsychological performance compared to individuals with mild cognitive impairment (MCI) and healthy controls (HC). DMN maps were derived from resting-state fMRI using independent component analysis. Group comparisons of DMN connectivity were performed between older adults with MCI (n = 18), CC (n = 23), and HC (n = 16). Both CC and MCI showed decreased DMN connectivity in the right hippocampus compared to HC, with the CC group showing greater connectivity than MCI. These differences survived atrophy correction and correlated with cognitive performance. DMN connectivity appears sensitive to early prodromal neurodegenerative changes associated with AD, notably including pre-MCI individuals with cognitive complaints.

健忘性軽度認知障害： デフォルトモードネットワークの位相的再組織化

Amnestic Mild Cognitive Impairment: Topological Reorganization of the Default-Mode Network.
Radiology. 2013 Mar 12;
Authors: Wang L, Li H, Liang Y, Zhang J, Li X, Shu N, Wang YY, Zhang ZJ


Purpose:To investigate the topologic reorganization of the default-mode network (DMN) in patients with mild cognitive impairment (MCI) and whether, relative to healthy control subjects, patients with MCI would be more likely to show disrupted functional connectivity and altered topological configuration of the DMN during the memory task compared with that observed during the resting state.Materials and Methods:This study was approved by the institutional review board of Beijing Normal University Imaging Center for Brain Research. Written informed consent was obtained from each participant. Healthy control subjects (n = 26) and patients with amnestic MCI (aMCI) (n = 25) performed an episodic memory task and also rested while undergoing functional magnetic resonance imaging. Task-induced deactivations were identified and parcellated into different regions associated with the DMN. Functional connectivity across all pairs of regions was computed to construct the DMN architecture. Graph theoretical approaches were used to characterize topological properties of this network.Results:Patients with aMCI showed similar deactivation in the DMN to that observed in healthy control subjects (P > .05) but showed significantly decreased anterior-to-posterior functional connectivity only during the task (P < .05). Significant increases in local efficiency (P < .05), but not in global efficiency (P > .05), were observed in aMCI only during the task. Decreased functional connectivity was predictive of increased local efficiency (r = -0.35, P = .015). Significant correlations between these network measures and cognitive performance (P < .05) indicated their potential use as early markers to assess the risk of Alzheimer disease (AD).Conclusion:This study suggests the early onset functional reorganization of the DMN toward a nonoptimized regularity configuration in aMCI and expands the understanding of dynamic functional reorganization in brain networks along the continuum from normal aging to AD dementia.