Psychosis
Brain diseases, such as Parkinson disease and Huntington disease
Brain tumors or cysts
Dementia (including Alzheimer disease)
HIV and other infections that affect the brain
Some prescription medicines, such as steroids and stimulants
Some types of epilepsy
Stroke
Even severe dehydration can cause Psychosis.
Ruling out all of those causes, nudity is also related to the demonic. We see this in examples from the Gospels and other accounts of demonic possession and oppression, and modern day exorcists confirm it.