Human brain continues growing all throughout a person's life. It has been found that even an 'old brain' can rewire itself and grow neurons or brain cells. Age-related memory loss is a result of lack of sufficient mental stimulation. Crossword puzzles, Sudoko and other such mentally-demanding puzzles stimulate the brain and help improve brain function and check cognitive decline. These exercises are particularly helpful in improving the left brain function which uses logic, knows facts and is detail-oriented.Improving your self esteem.