Social withdrawal

Solitude is a state of seclusion or isolation, i.e., lack of contact with people. It may stem from bad relationships, loss of loved ones, deliberate choice, infectious disease, mental disorders, neurological disorders or circumstances of employment or situation (see castaway).

Short-term solitude is often valued as a time when one may work, think or rest without being disturbed. It may be desired for the sake of privacy.

A distinction has been made between solitude and loneliness. In this sense, these two words refer, respectively, to the joy and the pain of being alone.

Symptoms from complete isolation, called sensory deprivation, often include anxiety, sensory illusions, or even distortions of time and perception. However, this is the case when there is no stimulation of the sensory systems at all, and not only lack of contact with people. Thus, by having other things to keep one's mind busy, this is avoided.

Still, long-term solitude is often seen as undesirable, causing loneliness or reclusion resulting from inability to establish relationships. Furthermore, it might even lead to clinical depression. However, for some people, solitude is not depressing. Still others (e.g. monks) regard long-term solitude as a means of spiritual enlightenment. Indeed, marooned people have been left in solitude for years without any report of psychological symptoms afterwards.

Enforced loneliness (solitary confinement) has been a punishment method throughout history. It is often considered a form of torture. In contrast, some psychological conditions (such as schizophrenia and schizoid personality disorder) are strongly linked to a tendency to seek solitude. In animal experiments, solitude has been shown to cause psychosis.

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