The modulation of BOLD variability between cognitive states varies by age and processing speed.

@article{Garrett2013TheMO,
  title={The modulation of BOLD variability between cognitive states varies by age and processing speed.},
  author={Douglas D. Garrett and Natasa Kovacevic and Anthony Randal McIntosh and Cheryl L. Grady},
  journal={Cerebral cortex},
  year={2013},
  volume={23 3},
  pages={
          684-93
        }
}
Increasing evidence suggests that brain variability plays a number of important functional roles for neural systems. However, the relationship between brain variability and changing cognitive demands remains understudied. In the current study, we demonstrate experimental condition-based modulation in brain variability using functional magnetic resonance imaging. Within a sample of healthy younger and older adults, we found that blood oxygen level-dependent signal variability was an effective… 

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