Theodor Meynert

Theodor Meynert (1833-1892) was a German-Austrian neuropathologist and anatomist who was born in Dresden. He is remembered as an early mentor of Sigmund Freud. Freud worked at Meynert's Psychiatric Clinic in Vienna in 1883. Meynert later distanced himself from Freud because of the latter's involvement with practices such as hypnosis. Also Meynert ridiculed Freud's idea of male hysteria. Other famous students of Meynert's were Russian neuropsychiatrist Sergei Korsakoff (1854-1900), German neuropathologist Carl Wernicke (1848-1905) and Swiss neuroanatomist Auguste-Henri Forel (1848–1931). He was a major influence in the career of German neuropathologist Paul Flechsig (1847-1929).

Meynert's work was largely focused on brain anatomy, pathology and histology, including the mapping of its intricate pathways and topography. He made many contributions involving the study of the cellular architecture of the brain and is often considered to be the founder of brain cytoarchitectonics. Meynert's aim was to establish psychiatry as an exact science based on anatomy.

Meynert postulated several theories regarding connections between anatomical and thought processes. For example, he believed in the coupling between one association and its temporal successor as a literal contact between cortical nerve cells physically connected to each other by nerve fibers. Also, he theorized that ideas and memories are to be envisioned as being attached to various brain cells. In his 1884 textbook ''Psychiatrie. Klinik der Erkrankungen des Vorderhirns'', Meynert forewords with the statement: "'The reader will find no other definition of 'Psychiatry' in this book but the one given on the title page: Clinical Treatise on Diseases of the Forebrain. The historical term for psychiatry, i.e., 'treatment of the soul,' implies more than we can accomplish, and transcends the bounds of accurate scientific investigation.'"

Meynert contributed his work concerning the structure of the mammalian brain to Salomon Stricker's (1834-1898) Handbuch der Lehre von den Geweben des Menschen und der Thiere. Two anatomical structures that are named after him are the basal optic nucleus of Meynert and the substantia innominata of Meynert. In 1869 Meynert described the dorsal tegmental decussation of the left and right tectospinal and tectobulbar tracts, located in the mesencephalon (midbrain). This was to become known as Meynert's decussation or fountain decussation.