For the Navy officer, see Jean-Marthe-Adrien l'Hermite
He was born in Mont-Saint-Père, Aisne, son of Léon Augustin Lhermitte, a French realist painter. Following his early education at Saint-Etienne, he studied in Paris and graduated in medicine in 1907. He specialised in neurology and became Chef-de-clinique (resident) for nervous diseases in 1908, Chef de laboratoire in 1910, and professeur agrégé for psychiatry 1922. He later became Médecin des Hôpitaux at the "Hospice Paul Brousse", head of the foundation "Dejerine", and clinical director at the Salpêtrière Hospital.
During World War I he studied spinal injuries and became interested in neuropsychiatry. This led to publications on visual hallucinations of the self. A deeply religious man, he explored the common territory between theology and medicine, and this led to interesting studies on demoniacal possession and stigmatisation.
Lhermitte was a noted clinical neurologist, and a number of medically relevant eponyms bear his name:
- Lhermitte's sign: Flexion of the neck in patients with multiple sclerosis produces electric shock-like sensations that extend down the spine and may shoot into the limbs.
- Lhermitte's peduncular hallucinosis: Purely visual hallucinations recognized as unreal, abnormal phenomena (preserved insight).
- Lhermitte's syndrome: A rare syndrome of ocular palsy with nystagmus and paralysis of adduction during attempted lateral deviation of the eyes.
- Lhermitte-Cornil-Quesnel syndrome: A slowly progressive pyramidopallidal degeneration.
- Lhermitte-Duclos syndrome: A rare pathologic entity with hypertrophy chiefly of the stratum granulosum of the cerebellum.
- Lhermitte-Lévy syndrome: A syndrome of slowly progressing paralysis after a stroke.
- Lhermitte-McAlpine syndrome: A combined pyramidal and extrapyramidal tract syndrome in middle-aged and elderly persons.
- Lhermitte-Trelles syndrome: A syndrome characterized by lymphoblastic infiltration of the peripheral nervous system, associated with paralysis and amyotrophy.
- Techniques anatomo-pathologiques du système nerveux. Paris, 1914
- Psycho-névroses de guerre. Paris, 1916
- Les blessures de la moelle épinière. Paris, 1917
- La section totale de la moelle épinière. Paris, 1918
- Les fondements biologiques de la psychologie. Paris, 1925
- Les hallucinations: clinique et physiopathologie. Paris, 1951