title: Cognitive training can reduce the rate of cognitive aging: a neuroimaging cohort study.
abstract: BACKGROUND
  The neural mechanisms underlying the restorative effects of cognitive training on aging brains remain unclear. To address this issue, we examined the relationship between changes in spontaneous brain activity and cognitive performance that occur after cognitive training.
  
  
  METHODS
  Participants were older adults who were part of a randomized control trial within a larger longitudinal cognitive training study. We conducted single-domain and multi-domain cognitive training in two respective intervention groups. Participants were trained for 1 h, twice a week, for 12 weeks. Cognition was assessed in all participants and magnetic resonance images were obtained at baseline and 1 year after training. To assess spontaneous fluctuations in brain activity, we acquired resting-state fMRI data. Two indices-functional entropy and time-domain entropy-were used to measure the effects of training. Functional entropy increases with aging, and indicates disruptions in functional conectivity. Time-domain entropy decreases with aging, and indicates structural alterations in the brain and blood-flow reduction.
  
  
  RESULTS
  Seventy participants completed the study: 26 in the multi-domain cognitive training group (70.38 ± 3.30 yrs), 27 in single-domain group (70.48 ± 3.93 yrs), and 17 in a control group (68.59 ± 3.24 yrs). Functional entropy increased significantly less in the multi-domain (p = 0.047) and single-domain groups (p = 9.51 × 10(-4)) compared with the control group. In the multi-domain group, this was true in the paracentral lobule (p = 0.004, Bonferroni corrected p < 0.05). Time-domain entropy also improved with training. Compared with controls, time-domain entropy in the multi-domain group decreased less in the inferior frontal gyrus pars opercularis (p = 3.59 × 10(-4)), the medial part of superior frontal gyrus (p = 1.17 × 10(-5)), and the thalamus (p = 4.72 × 10(-5)), while that in the single-domain group decreased less in the cuneus (p = 2.58 × 10(-4), Bonferroni corrected p < 0.05). Additionally, changes in regional entropy for some regions such as hippocampus significantly correlated with improvements in cognitive performance.
  
  
  CONCLUSIONS
  Cognitive training can induce plastic changes in neural functional connectivity of healthy older people, and these changes may underlie the positive effect of cognitive training.
  
  
  BACKGROUND
  ChiCTR-TRC-08000732 (Date of registration: 5th November, 2008).
authors.affiliation: Shanghai Key Laboratory of Psychotic Disorders, Shanghai Mental Health Center, Shanghai Jiao Tong University School of Medicine, Shanghai, China.
authors.forename: Ting
authors.initials: T
authors.lastname: Li
authors.affiliation: Centre for Computational Systems Biology, Fudan University, Shanghai, China.|Department of Computer Science, University of Warwick, Coventry, CV4 7AL, UK.
authors.forename: Ye
authors.initials: Y
authors.lastname: Yao
authors.affiliation: Department of Psychiatry, Tongji Hospital of Tongji University, Shanghai, China.
authors.forename: Yan
authors.initials: Y
authors.lastname: Cheng
authors.affiliation: Centre for Computational Systems Biology, Fudan University, Shanghai, China.|Department of Computer Science, University of Warwick, Coventry, CV4 7AL, UK.
authors.forename: Bing
authors.initials: B
authors.lastname: Xu
authors.affiliation: Shanghai Key Laboratory of Psychotic Disorders, Shanghai Mental Health Center, Shanghai Jiao Tong University School of Medicine, Shanghai, China.
authors.forename: Xinyi
authors.initials: X
authors.lastname: Cao
authors.affiliation: Centre for Computational Systems Biology, Fudan University, Shanghai, China.
authors.forename: David
authors.initials: D
authors.lastname: Waxman
authors.affiliation: Department of Psychiatry, Tongji Hospital of Tongji University, Shanghai, China.
authors.forename: Wei
authors.initials: W
authors.lastname: Feng
authors.affiliation: Department of Psychiatry, Tenth People's Hospital of Tongji University, Shanghai, China.
authors.forename: Yuan
authors.initials: Y
authors.lastname: Shen
authors.affiliation: Department of Psychiatry, Tongji Hospital of Tongji University, Shanghai, China.
authors.forename: Qingwei
authors.initials: Q
authors.lastname: Li
authors.affiliation: Shanghai Key Laboratory of Psychotic Disorders, Shanghai Mental Health Center, Shanghai Jiao Tong University School of Medicine, Shanghai, China.
authors.forename: Jijun
authors.initials: J
authors.lastname: Wang
authors.affiliation: Department of Psychiatry, Tongji Hospital of Tongji University, Shanghai, China.
authors.forename: Wenyuan
authors.initials: W
authors.lastname: Wu
authors.affiliation: Shanghai Key Laboratory of Psychotic Disorders, Shanghai Mental Health Center, Shanghai Jiao Tong University School of Medicine, Shanghai, China. chunbo_li@163.com.
authors.forename: Chunbo
authors.initials: C
authors.lastname: Li
authors.affiliation: Centre for Computational Systems Biology, Fudan University, Shanghai, China. jffeng@fudan.edu.cn.|Shanghai Center for Mathematical Sciences, Fudan University, Shanghai, China. jffeng@fudan.edu.cn.|Department of Computer Science, University of Warwick, Coventry, CV4 7AL, UK. jffeng@fudan.edu.cn.
authors.forename: Jianfeng
authors.initials: J
authors.lastname: Feng
mesh_terms: D000368:Aged; D001921:Brain / Q000473:pathology / Q000503:physiopathology; D003071:Cognition / Q000502:physiology*; D003072:Cognition Disorders / Q000175:diagnosis / Q000209:etiology / Q000503:physiopathology / Q000517:prevention & control; D000066492:Cognitive Aging / Q000502:physiology*; D015331:Cohort Studies; D005260:Female; D059907:Functional Neuroimaging / Q000379:methods; D006801:Humans; D007858:Learning / Q000502:physiology*; D008137:Longitudinal Studies; D008279:Magnetic Resonance Imaging / Q000379:methods; D008297:Male; D017063:Outcome Assessment, Health Care