Psychologists is the scientific study of behavior and mental processes. There are several fields of psychology including clinical, counseling, school, educational, developmental, social, and environmental psychologists. Clinical psychologists diagnose and treat mental and behavioral disorders while counseling psychologists help with adjustment issues. School psychologists assist students with learning problems and placements in special classes. Educational psychologists study human learning and memory. Developmental psychologists examine lifespan changes. Social psychologists analyze how people are influenced by others. Environmental psychologists explore human-environment interactions.