Avolition and expressive deficits capture negative symptom phenomenology: Implications for DSM-5 and schizophrenia research

The DSM-5 formulation presents an opportunity to refine the negative symptom assessments that are crucial for a schizophrenia diagnosis. This review traces the history of negative symptom constructs in neuropsychiatry from their earliest conceptualizations in the 19th century. It presents the relevant literature for distinguishing between different types of negative symptoms. Although a National Institute of Mental Health consensus initiative proposed that there are five separate negative symptom domains, our review of the individual items demonstrates no more than three negative symptom domains. Indeed, numerous factor analyses of separate negative symptom scales routinely identify only two domains: 1) expressive deficits, which include affective, linguistic and paralinguistic expressions, and 2) avolition for daily life and social activities. We propose that a focus on expressive deficits and avolition will be of optimum utility for diagnosis, treatment-considerations, and research purposes compared to other negative symptom constructs. We recommend that these two domains should be assessed as separate dimensions in the DSM-5 criteria.

Research Highlights
► Debate persists regarding the definitions of negative symptoms in schizophrenia.
► Negative symptoms encompass two domains: expressive deficits and avolition.
► These two domains offer the best hope for developing new treatment approaches.
► Clarification is still needed regarding the nature of anhedonia in schizophrenia.