Believing strongly in psychology and psychiatry, I believe that brain chemistry can dictate our mood changes at times and how we handle and react to situations. I do believe that environmental factors can play strongly in one's emotions, however ultimately one person may handle things better or be able to overcome depression better than another due to their brain chemistry, the hormones in their body, and their biological make-up. I know that my family has a history of addiction, personality disorders and swift mood changes. People are definitely affected by enviornmental factors, however what someone has biologically going on upstairs affects how they will ultimately handle affairs in their own lives. Most importantly, if someone is aware of the chemical tendencies they have, they can work with them to have them positively move in their favor.