I

IZARD

EMOTION

ICD-10

tenth revision of the International Classification of Diseases published by the World Health Organization, Geneva (1992)

Id

unconscious part of the mental apparatus which is partly made up of inherited instincts and partly by acquired, but repressed components.

Ideas of reference

see under delusion of reference.

Illusion

false perception of a real external stimulus.

Inappropriate affect

affect that is inappropriate to the circumstances

Induced psychosis/ folie à deux

delusional disorder shared by two or more people who are closely related emotionally. One has a real psychosis whilst symptoms are induced in the other. Separation results in symptomatic improvement in the one who is not psychotic.

Introjection and identification

ego defence mechanisms in which the attitudes and behaviour of another are internalised to help the person to cope with separation

Isolation

a defense mechanism in which certain thoughts are isolated from others