title: Increased Intraregional Synchronized Neural Activity in Adult Brain After Prolonged Adaptation to High-Altitude Hypoxia: A Resting-State fMRI Study.
abstract: The human brain is intrinsically plastic such that its functional architecture can be reorganized in response to environmental pressures and physiological changes. However, it remains unclear whether a compensatory modification of spontaneous neural activity occurs in adult brain during prolonged high-altitude (HA) adaptation. In this study, we obtained resting-state functional magnetic resonance (MR) images in 16 adults who have immigrated to Qinghai-Tibet Plateau (2300-4400 m) for 2 years and in 16 age-matched sea level (SL) controls. A validated regional homogeneity (Reho) method was employed to investigate the local synchronization of resting-state functional magnetic resonance imaging (fMRI) signals. Seed connectivity analysis was carried out subsequently. Cognitive and physiological assessments were made and correlated with the image metrics. Compared with SL controls, global mean Reho was significantly increased in HA immigrants as well as a regional increase in the right inferolateral sensorimotor cortex. Furthermore, mean z-Reho value extracted within the inferolateral sensorimotor area showed trend-level significant inverse correlation with memory search reaction time in HA immigrants. These observations, for the first time, provide evidence of adult brain resilience of spontaneous neural activity after long-term HA exposure without inherited and developmental effects. Resting-state fMRI could yield valuable information for central mechanisms underlying respiratory and cognitive compensations in adults during prolonged environmentally hypoxic adaptation, paving the way for future HA-adaptive training.
authors.affiliation: 1 Department of Physiology and Neurobiology, Medical College of Xiamen University , Xiamen, Fujian, China .|2 Department of Medical Imaging Center, Fuzhou General Hospital of Nanjing Military Area Command of Chinese PLA , Fuzhou, Fujian, China .
authors.forename: Ji
authors.initials: J
authors.lastname: Chen
authors.affiliation: 1 Department of Physiology and Neurobiology, Medical College of Xiamen University , Xiamen, Fujian, China .
authors.forename: Cunxiu
authors.initials: C
authors.lastname: Fan
authors.affiliation: 3 Department of Clinical Psychology, Gulangyu Sanatorium of PLA , Xiamen, Fujian, China .
authors.forename: Jinqiang
authors.initials: J
authors.lastname: Li
authors.affiliation: 3 Department of Clinical Psychology, Gulangyu Sanatorium of PLA , Xiamen, Fujian, China .
authors.forename: Qiaoqing
authors.initials: Q
authors.lastname: Han
authors.affiliation: 4 Magnetic Resonance Center, Zhongshan Hospital, Medical College of Xiamen University , Xiamen, Fujian, China .
authors.forename: Jianzhong
authors.initials: J
authors.lastname: Lin
authors.affiliation: 4 Magnetic Resonance Center, Zhongshan Hospital, Medical College of Xiamen University , Xiamen, Fujian, China .
authors.forename: Tianhe
authors.initials: T
authors.lastname: Yang
authors.affiliation: 1 Department of Physiology and Neurobiology, Medical College of Xiamen University , Xiamen, Fujian, China .
authors.forename: Jiaxing
authors.initials: J
authors.lastname: Zhang
mesh_terms: D000064:Acclimatization / Q000502:physiology*; D000531:Altitude; D000532:Altitude Sickness / Q000000981:diagnostic imaging / Q000503:physiopathology*; D001921:Brain / Q000000981:diagnostic imaging / Q000503:physiopathology*; D016022:Case-Control Studies; D006801:Humans; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008297:Male; D012146:Rest / Q000502:physiology; D066191:Sensorimotor Cortex / Q000000981:diagnostic imaging / Q000503:physiopathology; D018609:Tibet; D055815:Young Adult
keywords: high altitude; hypoxia; regional homogeneity; resting-state fMRI