Psychiatric illnesses can present with medically unexplained symptoms, which may be elicited consciously or unconsciously.
In somatic disorders, the symptoms develop unconsciously, however, there is no medical basis or organic disease to suggest their cause. On the other hand, in factitious disorders, a person knowingly shows signs and symptoms with an underlying motive.
If symptoms are being faked to evade work or punishment, the attempt is called malingering.
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