Neuroimaging has proven informative about the structural and functional changes in the aging brain and how these relate to cognitive decline. Task-free and task-based fMRI methods are particularly promising for studying age-related changes in brain functional connectivity networks and vulnerable patterns in ageing-related disorders. Accumulating evidence suggest that healthy ageing is linked to a decline in the functional specialization and segregation of intrinsic connectivity networks. In this talk, I will focus on longitudinal healthy ageing studies linking brain functional connectivity to cognition from our group. We found that greater functional connectivity increases between the default mode and control networks, i.e., loss of segregation between the two networks, related to faster declines in processing speed over time in healthy older adults. We have also demonstrated that APOE4 carriers had faster decline in functional segregation between the default mode and control networks, suggesting an accelerated aging pattern. One step further, using graph theoretical and community detection approaches to study task-free functional network changes in a cross-sectional young and longitudinal healthy elderly cohort, we showed that ageing was associated with global declines in network segregation, integration, and module distinctiveness, especially in the higher-order cognitive networks. Lastly, I will present some emerging data from the lab showing brain network segregation and integration differences between adolescents, young, and older adults from resting-state to task and their associations with task performance. These findings push beyond node-specific differences to connect ageing-related changes in brain network connectivity with ageing-related decline in cognitive performance.
Dr. Juan (Helen) Zhou is an Associate Professor at the Center for Cognitive Neuroscience, Neuroscience and Behavioral Disorders Program, Duke-National University of Singapore Medical School, Singapore. She also holds a joint appointment as Principal Investigator with Clinical Imaging Research Center, National University of Singapore. Her lab studies selective brain network-based vulnerability in neuropsychiatric disorders such as dementia and psychosis using multimodal neuroimaging and machine learning approaches.
Prior to joining Duke-NUS in 2011, Helen was an associate research scientist at Department of Child and Adolescent Psychaitry, New York University. She did a post-doctoral fellowship at the Memory and Aging Center, Department of Neurology, University of California, San Francisco, from 2008 to 2010 and one-year research fellow in the Computational Biology Program at Singapore-MIT Alliance in 2007-2008. Helen received her Bachelor degree in Computer Science and Engineering with first class honour in 2003 under the scholarship from the Ministry of Education, Singapore and her Ph.D. in 2008 from School of Computer Science and Engineering, Nanyang Technological University, Singapore.
Helen has more than 65 publications in international peer-reviewed high impact journals such as Neuron, Brain, PNAS, Neurology, Molecular Psychiatry, Biological Psychiatry, Journal of Neuroscience, NeuroImage, Cerebral Cortex and so on. She is the Council member – Secretary and a program committee member of the Organization of Human Brain Mapping, a member of the IEEE, Society for Neuroscience, American Academy of Neurology, and Alzheimer’s Association. Helen also serves as an Editor of NeuroImage and Associate Editors of other journals. Dr. Zhou has been the recipient of research support from National Medical Research Council and Biomedical Research Council, Singapore as well as the Royal Society, UK.
Please register for a seat here.