The Stanford Center on Longevity and 70+ of the world’s leading cognitive psychologists and neuroscientists (signatories) issue a position statement on brain training.
Max Planck Institute for Human Development and Stanford Center on Longevity (2014). A consensus on the brain training industry from the scientific community. http://longevity3.stanford.edu/blog/2014/10/15/the-consensus-on-the-brain-training-industry-from-the-scientific-community/
