title: Primary and persistent negative symptoms: Concepts, assessments and neurobiological bases.
abstract: Primary and persistent negative symptoms (PPNS) represent an unmet need in the care of people with schizophrenia. They have an unfavourable impact on real-life functioning and do not respond to available treatments. Underlying etiopathogenetic mechanisms of PPNS are still unknown. The presence of primary and enduring negative symptoms characterizes deficit schizophrenia (DS), proposed as a separate disease entity with respect to non-deficit schizophrenia (NDS). More recently, to reduce the heterogeneity of negative symptoms by using criteria easily applicable in the context of clinical trials, the concept of persistent negative symptoms (PNS) was developed. Both PNS and DS constructs include enduring negative symptoms (at least 6months for PNS and 12months for DS) that do not respond to available treatments. PNS exclude secondary negative symptoms based on a cross-sectional evaluation of severity thresholds on commonly used rating scales for positive symptoms, depression and extrapyramidal side effects; the DS diagnosis, instead, excludes all potential sources of secondary negative symptoms based on a clinical longitudinal assessment. In this paper we review the evolution of concepts and assessment modalities relevant to PPNS, data on prevalence of DS and PNS, as well as studies on clinical, neuropsychological, brain imaging electrophysiological and psychosocial functioning aspects of DS and PNS.
authors.affiliation: Department of Psychiatry, University of Naples SUN, Naples, Italy. Electronic address: armida.mucci@gmail.com.
authors.forename: Armida
authors.initials: A
authors.lastname: Mucci
authors.affiliation: Department of Psychiatry, University of Naples SUN, Naples, Italy.
authors.forename: Eleonora
authors.initials: E
authors.lastname: Merlotti
authors.affiliation: Department of Psychiatry, Psychotic Disorders Research Program, Istanbul Faculty of Medicine, Istanbul, Turkey.
authors.forename: Alp
authors.initials: A
authors.lastname: Üçok
authors.affiliation: University of Groningen, University Medical Center Groningen, Department of Neuroscience and Department of Psychology, Groningen, The Netherlands.
authors.forename: André
authors.initials: A
authors.lastname: Aleman
authors.affiliation: Department of Psychiatry, University of Naples SUN, Naples, Italy.
authors.forename: Silvana
authors.initials: S
authors.lastname: Galderisi
mesh_terms: D001921:Brain / Q000000981:diagnostic imaging / Q000473:pathology* / Q000503:physiopathology*; D003072:Cognition Disorders / Q000175:diagnosis / Q000209:etiology; D006801:Humans; D009446:Neurobiology; D059906:Neuroimaging; D011569:Psychiatric Status Rating Scales; D012559:Schizophrenia / Q000150:complications / Q000175:diagnosis / Q000473:pathology; D012565:Schizophrenic Psychology
keywords: Deficit schizophrenia; Electrophysiology; Neurocognition; Neuroimaging; Persistent negative symptoms; Real-life functioning