Catatonia is a state of psycho-motor immobility and behavioral abnormality manifested by stupor. It was first described in 1874 by Karl Ludwig Kahlbaum as Die Katatonie oder das Spannungsirresein (Catatonia or Tension Insanity). Though catatonia has historically been related to schizophrenia, it is now known that catatonic symptoms are nonspecific and may be observed in other mental disorders and neurological conditions. In the fifth edition of the Diagnostic and Statistical Manual of Mental Disorders (DSM), catatonia is not recognized as a separate disorder but is associated with psychiatric conditions such as schizophrenia, bipolar disorder, post-traumatic stress disorder, depression, narcolepsy, drug abuse or overdose.