Every thing psychological is simultaneously biological. Every mood, every urge, every idea is a biological happening. When a person talks his mood overcome his feelings and he react according to his emotions. This all happening a biological changes in human body. A person might feel happy at a moment but at the same time when he hears some news he becomes sad or emotions within seconds. This is due to neurons which gives messages to the brain and biological changes reacts in human to make him emotional.
