Each year, millions of people experience seasonal affective disorder or SAD. Today we talk to neuroscientist-turned-journalist Richard Sima about how to get ready for the change in season and beat the winter depression.Read more:Susceptible people — an estimated 5 percent of Americans — already are feeling the effects of winter SAD: lower moods, lethargy and excessive sleep. Today on “Post Reports,” we talk about strategies that can help you cope.Subscribe to The Washington Post here.