Brain Imaging and Behavior

, Volume 8, Issue 2, pp 274–283 | Cite as

Understanding variability in the BOLD signal and why it matters for aging

  • Cheryl L. Grady
  • Douglas D. Garrett
SI: Genetic Neuroimaging in Aging and Age-Related Diseases


Recent work in neuroscience supports the idea that variability in brain function is necessary for optimal brain responsivity to a changing environment. In this review, we discuss a series of functional magnetic resonance imaging (fMRI) studies in younger and older adults to assess age-related differences in variability of the fMRI signal. This work shows that moment-to-moment brain signal variability represents an important “signal” within what is typically considered measurement-related “noise” in fMRI. This accumulation of evidence suggests that moving beyond the mean will provide a complementary window into aging-related neural processes.


fMRI BOLD signal Variability Aging Cognition 



This work was supported by the Canadian Institutes of Health Research (grant #MOP14036). C.L.G. also is supported by the Canada Research Chairs program, the Ontario Research Fund, and the Canadian Foundation for Innovation.


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Copyright information

© Springer Science+Business Media New York 2013

Authors and Affiliations

  1. 1.Rotman Research Institute at BaycrestTorontoCanada
  2. 2.Departments of Psychiatry and PsychologyUniversity of TorontoTorontoCanada
  3. 3.Max Planck Society-University College London Initiative in Computational Psychiatry and Aging Research (ICPAR) Center for Lifespan PsychologyMax Planck Institute for Human DevelopmentLondonUK

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