In shamanistic traditions, it is stated that parts of the soul can separate from us and that this separation, this loss of soul parts, can be a cause of physical and mental illness.
From various traditions, including shamanic traditions, anthroposophy and Hinduism, we know the concept of the human being consisting of several bodies and not just a physical body.
Each tradition has its own concept about the physical, gross material, and subtle or energetic bodies.
Apart from the physical body, we cannot see those other bodies with our well-known senses. We can observe these energetic bodies, for example, with the help of Systemic Ritual or Shamanic journeys.