Differentially disrupted functional connectivity of the subregions of the amygdala in Alzheimer’s disease

Article type: Research Article

Authors: Wang, Zhiqun^a | Zhang, Min^b | Han, Ying^c | Song, Haiqing^c | Guo, Rongjuan^{d; *} | Li, Kuncheng^{b; e; *}

Affiliations: [a] Department of Radiology, Dongfang Hospital, Beijing University of Chinese Medicine, Beijing, China | [b] Department of Radiology, Xuanwu Hospital of Capital Medical University, Beijing, China | [c] Department of Neurology, Xuanwu Hospital of Capital Medical University, Beijing, China | [d] Department of Neurology, Dongfang Hospital, Beijing University of Chinese Medicine, Beijing, China | [e] Beijing Key Laboratory of Magnetic Resonance Imaging and Brain Informatics, Beijing, China

Correspondence: [*] Corresponding author: Kuncheng Li, Xuanwu Hospital of Capital Medical University, Beijing 100053, China. Tel.: +86 10 8319 8376; E-mail: likuncheng1955@126.com.

Correspondence: [*] Corresponding author: Rongjuan Guo, Dongfang Hospital, Beijing University of Chinese Medicine, Beijing 100078, China. Tel.: +86 10 6769 3481; E-mail: guorongjuandf@126.com.

Abstract: The amygdala is an important brain area involved in cognitive procession and emotional regulation. Previous studies have typically considered the amygdala as a single structure, which likely masks contribution of individual amygdala subdivisions. Actually, the amygdala is heterogeneous and composed of structurally and functionally distinct nuclei, which may present different connectivity patterns and predict to relevant cognitive deficits in Alzheimer’s disease (AD). However, little is known about functional connectivity of amygdala subregions in the resting state in AD subjects. Here, we employed resting-state functional MRI (fMRI) to examine functional connectivity changes of subregions comparing the AD patients with the age-matched control subjects. Thirty-two AD and 38 control subjects were analyzed. We defined three subregions of the amygdala according to probabilistic cytoarchitectonic atlases and mapped the whole-brain resting-state functional connectivity for each subregion: The central medial nucleus (CM) of amygdala exhibited connections with the lentiform nucleus, parahippocampus and lateral temporal gyrus; the lateral basal nucleus (LB) of amygdala functionally connected with the parahippocampus, lateral temporal gyrus, middle occipital gyrus and medial prefrontal cortex; and the superficial nucleus (SF) of amygdala had connection with the parahippocampus, lentiform nucleus, lateral temporal gyrus, insula, middle occipital gyrus, precentral and postcentral gyrus. Comparing with the controls, the AD patients presented disrupted connectivity patterns in the LB of amygdala, which predicted disconnection with the left uncus, right insula, right precentral gyrus, the left superior temporal gyrus and right claustrum. These findings in a large part supported our hypothesis and provided a new insight in understanding the pathophysiological mechanisms of AD.

Keywords: Amygdala, functional connectivity, functional MRI, Alzheimer disease

DOI: 10.3233/XST-160556

Journal: Journal of X-Ray Science and Technology, vol. 24, no. 2, pp. 329-342, 2016