delusion v. hallucination

A delusion is a strongly held false belief that persists despite evidence to the contrary. A delusional individual may believe that she is being spied on or ridiculed, that she has special powers, or that song lyrics contain hidden messages directed specifically at her.

A hallucination is the conscious perception of something (images, sounds, odors, etc.) in the absence of any external stimulus. Examples of hallucinations include hearing voices talking about you, experiencing unpleasant smells, or seeing ghosts.

A delusion an untrue belief; a hallucination is an unreal perception.

PsychCentral on delusion v. hallucination

psychosis v. neurosis

Psychosis

Psychosis is a severe mental disorder characterized by loss of contact with objective reality, brought about by delusions, hallucinations, and disordered thinking. Psychotics exhibit unusual behavior, undergo radical personality changes, and are not able to function normally. Psychosis may not be permanent, and can be treated with medication or psychotherapy.

Neurosis

A neurosis is a milder mental or emotional disorder not involving delusions and hallucinations. Neuroses include anxiety, insecurity, depression, irrational fears, hypochondria, obsessive-compulsive disorder, and some tics. Neurotics may be able to lead relatively normal, functional lives. Neurosis is usually treated with psychotherapy. The term neurosis is no longer in scientific use.

HubPages on psychosis v. neurosis

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id v. ego v. superego

In Freudian theory, the psyche is divided into 3 aspects: the id, the ego, and the superego.

• The id is the unconscious, instinctual part of the mind associated with the immediate satisfaction of basic needs such as food and sex. The id seeks pleasure and avoids pain.
• The ego is the rational, conscious self - the division that remembers, plans, and responds to external reality.
• The superego develops during childhood as the internalization of morals learned from parents and society. It acts as a conscience, keeping the ego in check by controlling socially unacceptable impulses.

About.com on id, ego, and superego