Psychologist study how the brain affects our whole body. Meaning the connections of what our thought process is and what the out come might become. They also study our subconscious mind. This is the part that we do not necessarily control. For example our dreams are in the subconscious mind and we have no control of it. We tend not to remember our whole dream just the ending of it. Psychologist study behaviour and decisions humans, animals, and insects make. To me they seem to figure out how they work related to the brain.