The Vitamin Linked To Better Sleep And Sharper Thinking (M) Taking higher doses of this supplement enhances sleep and cognition in people with dementia. Taking higher doses of this supplement enhances sleep and cognition in people with dementia. Keep reading with a Membership • Read members-only articles • Adverts removed • Cancel at any time • 14 day money-back guarantee for new members Become a member Username or E-mail Password Remember Me Forgot Password