Negative symptoms, past and present: a historical perspective and moving to DSM-5.

The diagnosis of schizophrenia includes "positive" and "negative" symptoms. These titles were developed to respectively reflect if the symptoms are additions to normal experiences, such as delusions and hallucinations, or if they refer to the absence or the loss of normal emotional function or behavior. This paper describes the history of the negative symptom concept, from its origins up to the considerations for the DSM-5, including the steps that produced the current conceptualizations. The DSM-5 only includes deficits in emotional expression and avolition as negative symptoms, which can be assessed from interview information. Factor analyses show they encompass most other negative symptom items. In addition to using these negative symptoms in a categorical manner to make a diagnosis, the DSM-5 has quantitative severity ratings of the negative symptoms, along with ratings of delusions, cognitive symptoms, motor symptoms, disorganization, depression and mania. With this approach, the different symptom domains, including negative symptoms, can be measured and tracked over time. Another change in the DSM-5 is the dropping of the schizophrenia subtypes that have been included in earlier volumes, as they were not useful in treatment decisions or prognosis. An intended outcome of these changes in DSM-5 is for clinicians to directly treat the individual psychopathological domains of the disorder for optimizing individual outcomes. Finally, this paper includes descriptions of the negative symptom items from over a dozen different scales.