Brain hothubs and dark functional networks: correlation analysis between amplitude and connectivity for Broca’s aphasia

PeerJ

article

Feng Lin¹  Shao-Qiang Cheng³  Dong-Qing Qi⁴  Yu-Er Jiang¹  Qian-Qian Lyu¹  Li-Juan Zhong¹  Zhong-Li Jiang¹ 

[1] Department of Rehabilitation Medicine, The First Affiliated Hospital of Nanjing Medical University;Department of Rehabilitation Medicine, The Affiliated Sir Run Run Hospital of Nanjing Medical University;Department of Neurology, The First People’s Hospital of Xianyang;The First Affiliated Hospital of USTC, Division of Life Sciences and Medicine, University of Science and Technology of China

关键词: Functional connectivity;    Source amplitude;    Aphasia;    Magnetoencephalography;    Phase-locking value;    Functional brain networks;    Network hubs;   

DOI  :  10.7717/peerj.10057

学科分类：社会科学、人文和艺术（综合）

来源: Inra

【 摘 要 】

Source localization and functional brain network modeling are methods of identifying critical regions during cognitive tasks. The first activity estimates the relative differences of the signal amplitudes in regions of interest (ROI) and the second activity measures the statistical dependence among signal fluctuations. We hypothesized that the source amplitude–functional connectivity relationship decouples or reverses in persons having brain impairments. Five Broca’s aphasics with five matched cognitively healthy controls underwent overt picture-naming magnetoencephalography scans. The gamma-band (30–45 Hz) phase-locking values were calculated as connections among the ROIs. We calculated the partial correlation coefficients between the amplitudes and network measures and detected four node types, including hothubs with high amplitude and high connectivity, coldhubs with high connectivity but lower amplitude, non-hub hotspots, and non-hub coldspots. The results indicate that the high-amplitude regions are not necessarily highly connected hubs. Furthermore, the Broca aphasics utilized different hothub sets for the naming task. Both groups had dark functional networks composed of coldhubs. Thus, source amplitude–functional connectivity relationships could help reveal functional reorganizations in patients. The amplitude–connectivity combination provides a new perspective for pathological studies of the brain’s dark functional networks.

【 授权许可】

CC BY