Depression

Negative symptoms

What are negative symptoms of schizophrenia?

Negative symptoms of schizophrenia refer to an absence of normal functions. These include a scarcity of facial expressions of emotion, reduced frequency and range of gestures and voice modulation, restricted eye contact, poverty of speech (alogia), reduced social interaction, reduced motivation (avolition), poor hygiene, and reduced experience of pleasure (anhedonia) which is often manifested as scarcity of recreation, inability to experience closeness, and reduced interest in any sexual activity. Deficit schizophrenia is a subtype of schizophrenia with persisting negative symptoms that is described by specifically defined assessments used primarily in research.

What is the evidence for negative symptoms?

Moderate to low quality evidence indicates negative symptoms occur in 50-90% of people with first-episode psychosis. This estimate decreases to 35-70% with treatment, but 20-40% of first-episode patients have persisting negative symptoms. There were more severe negative symptoms in patients with a family history of psychosis than in patients without a family history of psychosis.

Moderate to high quality evidence shows people with chronic schizophrenia report more anhedonia, and less consummatory and anticipatory pleasure than controls. There were small to medium-sized associations between more overall negative symptoms and more episodic memory deficits, more depression symptoms, less insight, and less motivation.

Moderate to high quality evidence finds deficit syndrome is apparent in around one-third of people with chronic schizophrenia. Deficit syndrome is associated with greater severity of negative and disorganised symptoms and less severity of mood symptoms. Deficit schizophrenia is more likely to occur in males than in females.

Moderate quality evidence finds large effects of longer pauses and less spoken time in people with schizophrenia compared to controls. There were medium-sized effects of lower speech rate and less pitch variability. No differences were found for pitch, intensity variability, duration of utterance and number of pauses. Significant associations were found between more negative symptoms and less pitch variability, greater flat affect, less time spoken, more alogia, and more duration of pauses.

Moderate to high quality evidence found no differences in negative symptoms between people with schizophrenia and current cannabis and/or nicotine use and people with schizophrenia with no cannabis and/or nicotine use. However, there was a small to medium-sized effect of less severe negative symptoms in people with schizophrenia who recently abstained from cannabis use.

March 2022

Image: ©Igor Stevanovic – stock.adobe.com

Last updated at: 4:06 pm, 21st March 2022
To view documentation related to this topic download the files below
Fact Sheet Technical Commentary

NeuRA Libraries

Title Colour Legend:
Green - Topic summary is available.
Orange - Topic summary is being compiled.
Red - Topic summary has no current systematic review available.