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Journal of Alzheimer’s Disease 42 (2014) 841–850 DOI 10.3233/JAD-140948 IOS Press
Aberrant Functional Networks Connectivity and Structural Atrophy in Silent Lacunar Infarcts: Relationship with Cognitive Impairments Yaojing Chena,b,c,1 , Jun Wanga,b,c,1 , Junying Zhanga,b,c , Ting Zhanga,b,c , Kewei Chend , Adam Fleisherd , Yongyan Wanga,b,c and Zhanjun Zhanga,b,c,∗ a State
Key Laboratory of Cognitive Neuroscience and Learning & IDG/McGovern Institute for Brain Research, Beijing Normal University, Beijing, P.R. China b Center for Collaboration and Innovation in Brain and Learning Sciences, Beijing Normal University, Beijing, P.R. China c BABRI Centre, Beijing Normal University, Beijing, P.R. China d Banner Alzheimer’s Institute, Phoenix, AZ, USA Handling Associate Editor: Xinqing Zhang
Accepted 23 April 2014
Abstract. Silent or asymptomatic lacunar infarcts (LACI) are common in elderly individuals, but it remains largely unclear how these often neglected silent brain infarcts lead to multiple domain cognitive deficits and even Alzheimer’s disease (AD). In this study, we investigated the difference between patients with silent LACI in basal ganglia region and healthy controls for the structural and functional changes in the aspects of alterations of gray matter (GM) volume and intra-/inter-default mode network (DMN) and salience network (SN) connectivity. Thirty patients with silent LACI in the basal ganglia region and thirty healthy controls participated in the study. Voxel-based morphometry analysis was employed to measure the GM volume. We further investigated the intra/inter-network connectivity of DMN and SN using resting-state functional magnetic resonance imaging. Compared with healthy controls, patients performed worse in cognitive function in the aspects of general mental status, attention, and memory. The LACIs showed more severe GM atrophy in insula, anterior cingulate cortex, caudate, and superior temporal pole than controls. The connectivity within and between two networks was also reduced in patients. Importantly, the disrupted connectivity correlated with the patients’ cognitive performance. Our findings support the hypothesis that silent lacunar infarcts result in cognitive decline, GM, and functional connectivity loss. Keywords: Cognition, functional connectivity, gray matter, network, silent stroke
INTRODUCTION Stroke is the second leading cause of death in China and is also considered the second most common cause 1 These
authors contributed equally to this work. to: Zhanjun Zhang, MD, State Key Laboratory of Cognitive Neuroscience and Learning, Beijing Normal University, Beijing 100875, China. Tel./Fax: +86 1058802005; E-mail: zhang [email protected]. ∗ Correspondence
of dementia, but the magnitude of the risk posed by stroke has not been fully clarified [1, 2]. Lacunar infarcts (LACI) are small cavitated ischemic infarcts, which are typically located in the subcortical areas of the basal ganglia (BG), thalamus, pons, corona radiate, and centrum semiovale [3]. Subcortical infarcts in the BG can result in executive dysfunction and memory deficits, which may be a downstream consequence of poor learning efficiency secondary to the executive
ISSN 1387-2877/14/$27.50 © 2014 – IOS Press and the authors. All rights reserved
Journal of Alzheimer’s Disease 42 (2014) 841–850 DOI 10.3233/JAD-140948 IOS Press
Aberrant Functional Networks Connectivity and Structural Atrophy in Silent Lacunar Infarcts: Relationship with Cognitive Impairments Yaojing Chena,b,c,1 , Jun Wanga,b,c,1 , Junying Zhanga,b,c , Ting Zhanga,b,c , Kewei Chend , Adam Fleisherd , Yongyan Wanga,b,c and Zhanjun Zhanga,b,c,∗ a State
Key Laboratory of Cognitive Neuroscience and Learning & IDG/McGovern Institute for Brain Research, Beijing Normal University, Beijing, P.R. China b Center for Collaboration and Innovation in Brain and Learning Sciences, Beijing Normal University, Beijing, P.R. China c BABRI Centre, Beijing Normal University, Beijing, P.R. China d Banner Alzheimer’s Institute, Phoenix, AZ, USA Handling Associate Editor: Xinqing Zhang
Accepted 23 April 2014
Abstract. Silent or asymptomatic lacunar infarcts (LACI) are common in elderly individuals, but it remains largely unclear how these often neglected silent brain infarcts lead to multiple domain cognitive deficits and even Alzheimer’s disease (AD). In this study, we investigated the difference between patients with silent LACI in basal ganglia region and healthy controls for the structural and functional changes in the aspects of alterations of gray matter (GM) volume and intra-/inter-default mode network (DMN) and salience network (SN) connectivity. Thirty patients with silent LACI in the basal ganglia region and thirty healthy controls participated in the study. Voxel-based morphometry analysis was employed to measure the GM volume. We further investigated the intra/inter-network connectivity of DMN and SN using resting-state functional magnetic resonance imaging. Compared with healthy controls, patients performed worse in cognitive function in the aspects of general mental status, attention, and memory. The LACIs showed more severe GM atrophy in insula, anterior cingulate cortex, caudate, and superior temporal pole than controls. The connectivity within and between two networks was also reduced in patients. Importantly, the disrupted connectivity correlated with the patients’ cognitive performance. Our findings support the hypothesis that silent lacunar infarcts result in cognitive decline, GM, and functional connectivity loss. Keywords: Cognition, functional connectivity, gray matter, network, silent stroke
INTRODUCTION Stroke is the second leading cause of death in China and is also considered the second most common cause 1 These
authors contributed equally to this work. to: Zhanjun Zhang, MD, State Key Laboratory of Cognitive Neuroscience and Learning, Beijing Normal University, Beijing 100875, China. Tel./Fax: +86 1058802005; E-mail: zhang [email protected]. ∗ Correspondence
of dementia, but the magnitude of the risk posed by stroke has not been fully clarified [1, 2]. Lacunar infarcts (LACI) are small cavitated ischemic infarcts, which are typically located in the subcortical areas of the basal ganglia (BG), thalamus, pons, corona radiate, and centrum semiovale [3]. Subcortical infarcts in the BG can result in executive dysfunction and memory deficits, which may be a downstream consequence of poor learning efficiency secondary to the executive
ISSN 1387-2877/14/$27.50 © 2014 – IOS Press and the authors. All rights reserved
