The role played by Bergsonism in recent neuro-psychiatric and psychological thought, and in the neurosciences in general, has been nearly non-existent. The term neuropsychiatry is used to express the dominant line of thought in the area of the pathology of the nervous system and mental illness in the period between the beginning of the 19th century and May, 1968. This chapter provides examination of the degree to which Bergson influenced the French neuropsychiatric and psychological thought with respect to three basic issues, namely the mind-body, the monism-dualism, and the idealism-materialism. It is discussed in the context of the following four dichotomies: philosophy vs. psychology; neurology vs. psychiatry; and organicism vs. psychogeneticism; holism vs localizationism. The Cartesian spirit of dualism, this ghost from the past haunted French neuropsychiatric thought for many years, and expressed itself mainly in the relations between neurology and psychiatry, between the brain and behaviour.