Scale for the Assessment of Negative Symptoms

Schizophrenia is a severe mental illness that is characterized by a range of behaviors including hallucinations and delusions. Hallucinations refer to disorders involving the sensory systems, and are most often manifested as seeing or hearing things (e.g., voices) that do not exist. Delusions include odd or unusual beliefs such as grandiosity or paranoia. Both hallucinations and delusions are inconsistent with reality. Other symptoms of schizophrenia include bizarre behavior, odd posture or movements, facial grimacing, loss of, or indifference to self-help skills (grooming, washing, toileting, feeding, etc.). Schizophrenia may also be marked by a host of social and communication deficits, such as social withdrawal, odd use of language, including excessive use of made up words (neologisms), incomprehensible combinations of words (word salad) or overall poverty of speech. There are several subtypes of schizophrenia, but generally speaking the symptoms are often classified into two broad categories: positive and negative symptoms. Positive symptoms refer to those behaviors or condition that are present in schizophrenia but that are not present under typical conditions (hallucinations, delusions). Negative symptoms refer to those behaviors that are conspicuous because of their absence (grooming, language, communication). Several measures or rating scales have been developed to assess the positive and negative aspects of schizophrenia.