Talking to oneself is not necessarily a mental illness, but may be related to the person’s personality. For example, people who are more introverted and shy may be reluctant to talk to others and tend to talk to themselves alone to relieve their loneliness. Especially when feeling very bored, or have a problem repeatedly thinking, this can deepen the impression. It is recommended that family and friends show more concern and support for the patient to avoid developing mental illnesses such as depression and schizophrenia. Self-talk can also be seen in the elderly and may be related to cognitive decline in the elderly, such as dementia. It can also be seen in functional psychiatric disorders such as dysthymia, depression, schizophrenia, and organic psychiatric disorders such as delirium state and epilepsy. All of these mental disorders have characteristic symptoms and can be diagnosed by a professional physician.