Julia A. Sherman, PhD and Unit 356 bridge player has written about how she recovered her memory playing duplicate bridge in her recent publication, Beating Depression and Bipolar Disorder Without Drugs published on Amazon, May 7, 2019.  Medicated to near oblivion, she couldn’t even remember what was trump! She is now nearing 1,500 masterpoints. 
From her own experience, and from the viewpoint of a professional psychologist, she says duplicate bridge is one of the best ways for seniors to keep their mental functioning. Bridge involves not only memory, but concentration, planning, judgment, and emotional control. Moreover, it’s a social game, and social relationships are absolutely vital to healthy human function.