Negative Symptoms of Schizophrenia (NSS)

Patients may experience negative symptoms of schizophrenia, which may include reduction or absence of behaviors related to motivation and interest or expression.

About Schizophrenia

Schizophrenia is a chronic, debilitating mental illness characterized by positive and negative symptoms, as well as cognitive and functional impairment.3 Approximately 1% of the US population develops schizophrenia during their lifetime.4

Negative symptoms are a core clinical feature of schizophrenia, affecting 30-to-60 percent of patients with the disorder.2,5 Negative symptoms of schizophrenia (NSS) are broadly defined as a reduction or absence of normal behaviors related to motivation and interest or expression.1,2

Negative Symptoms Include the Five ‘A”s1,2 

  • Avolition (decrease in the motivation to initiate and perform self-directed, purposeful activities)
  • Alogia (poverty of speech)
  • Anhedonia (reduced ability to experience pleasure)
  • Asociality (withdrawal from social interactions)
  • Affective flattening/blunting (diminished emotional expression)

The Impact of NSS on Patients

NSS is one of the main predictors of decreased quality of life in patients with schizophrenia.6 NSS is associated with impairments in occupational functioning, household integration, relationships, and recreational activities.7 The severity of NSS is linked to is linked to worse functional outcomes.8,9


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