Patients with schizophrenia show catatonic symptoms, psychomotor slowing and neurological soft and neurological hard signs. Similarly, Bipolar and unipolar depressive disorder patients can display catatonia and/or psychomotor slowing.
These psychomotor symptoms are intrinsic features of psychotic and mood disorders and cannot be seen as side effects of antipsychotic or other medication. They appear to progressively worsen during the illness and are associated with poor outcome, especially in schizophrenia. Psychomotor symptoms, unlike cognitive symptoms, are associated with positive symptoms. The different psychomotor symptoms are linked to the same brain structures. The symptoms may also be interrelated.
Several past research projects have investigated the psychomotor syndrome in these illnesses, with a strong focus on the processes involved in psychomotor slowing.