a psychopathological syndrome whose main clinical manifestation consists of motor disturbances that are unmotivated in nature, that is, not determined by the situation or other psychopathological syndromes. Within the structure of catatonic syndrome, catatonic excitement (see Catatonic Excitement in Chapter 2.1. Key Psychological Concepts in Clinical Psychology) and catatonic stupor (see Catatonic Stupor in Chapter 2.1. Key Psychological Concepts in Clinical Psychology) are distinguished, both accompanied by muscular tension. This syndrome was first described by the German psychiatrist K. Kahlbaum in 1874.