The neuropsychiatric term catatonia was born in the 19^th century. We explored primary source documents to define the founder’s intent for its application in neurology and psychiatry.

Catatonia was originally described as a ‘tonic-mental disorder’ in 1874 by Dr. Karl Ludwig Kahlbaum, which included 17 distinct clinical signs or symptoms. Since its introduction to clinical medicine, the term catatonia has posed a challenge for clinicians due to its broad definition and all-encompassing symptoms.

The primary and secondary published literature on catatonia were reviewed. The first written work applied the word “die katatonie” (Greek: Kata= down, Tonus= tension) and proposed a loose definition. Subsequent publications have proposed various applications of the term.  

We will present the results of the primary literature review and the subsequent secondary publications. Our review of the criteria proposed by the Diagnostic and Statistics Manual (DSM version III, IV, and V), International Classification of Disease (ICD-11), and Busch-Francis Catatonia Screening Instrument (BFCSI) reveal that waxy flexibility and catalepsy are the most distinct features of catatonia across publications. Although widely described in the context of schizophrenia, a diverse array of etiologies has been subsequently reported, including autoimmune, substance use or withdrawal, CNS infection, and others.

Catatonia is an umbrella term usually applied to describe clinical features associated with encephalopathy. The original term was never intended to be applied as a singular diagnosis, but it was rather a descriptive term for many features now associated with encephalopathy. Establishing a consensus among psychiatrists and movement disorders neurologists is imperative to deconstruct and redefine this 150-year-old terminology.