Most individuals with dementia or mild cognitive impairment (a reduction in thinking ability) develop behavioral changes, such as depression and agitation, over time. Which is preceding? A study published online by Neurology on January 14, 2015, indicates that psychological and behavioral changes may occur before moderate cognitive impairment or dementia develops. Researchers analyzed the everyday functioning, memory and thinking abilities, as well as psychological and behavioral symptoms of over 2,400 individuals aged 50 and older who showed no signs of cognitive impairment. The study also implies that older persons may exhibit a pattern of depressed symptoms unrelated to cognitive deterioration. What is the takeaway? "There are numerous causes for older persons to experience depressive symptoms. If you are having mood or cognitive changes that continue more than a few weeks, you should discuss this with your doctor or visit a mental health professional for assistance in determining possible causes "says Dr. Nancy Donovan, a Harvard Medical School psychiatry instructor.