Cognition: A general term covering the functions involved in dealing with information, for example perception, attention, memory and reasoning.   
Depression: An emotional state characterised by sadness, unhappy thought, apathy and dejection.
Unconscious: An absence of awareness. It refers to the part of personality of which the individual is unaware.  
Phobia: An excessive irrational fear of am object or situation. Eg. Fear of water.
Neurosis: A general term referring to emotional disorders such as anxiety, depression and obsession.
