John Bauer is a Swedish artist who was trapped by the enchantment of the forest and once said he never painted anything he hadn't seen. This is an unusual claim in context because of the things he painted.
From Quora: In 2007 in France, a 44-year-old man went to the doctor complaining of numbness in his leg and underwent a brain CT scan that revealed a shocking truth:
That man didn't have 90% of his brain. The skull was almost entirely filled with cerebrospinal fluid and all that remained of the brain was a thin peripheral portion surrounding the skull. You can plainly see this from the X-ray images below: