psychosomatist
/ˌsʌɪkəʊˈsəʊmətɪst/noun
A believer in an intimate relationship between the mind and the body; specifically an expert or specialist in, or an advocate of, psychosomatic medicine.
Origin
Early 19th century; earliest use found in Samuel Taylor Coleridge (1772–1834), poet, critic, and philosopher. Apparently from psychosomat- + -ist.