Neurocognitive Impairments in Deficit and Non-Deficit Schizophrenia and Their Relationships with Symptom Dimensions and Other Clinical Variables

Abstract

BackgroundDeficit schizophrenia (DS) has been proposed as a pathophysiologically distinct subgroup within schizophrenia. Earlier studies focusing on neurocognitive function of DS patients have yielded inconsistent findings ranging from substantial deficits to no significant difference relative to non-deficit schizophrenia patients (NDS). The present study investigated the severity and characteristic patterns of neurocognitive impairments in DS and NDS patients and their relationships with clinical variables.MethodsAttention, ideation fluency, cognitive flexibility and visuospatial memory function were assessed in 40 DS patients, 57 NDS patients, and 52 healthy controls by a comprehensive neuropsychological battery.ResultsBoth schizophrenia subgroups had overall more severe cognitive impairments than controls while DS performed worse on every neuropsychological measure except the Stroop interference than the NDS patients with age and education as the covariates. Profile analysis found significantly different patterns of cognitive profiles between two patients group mainly due to their differences in attention and cognitive flexibility functions. Age, education, illness duration and negative symptoms were found to have the correlations with cognitive impairments in the NDS group, while only age and the negative symptoms were correlated with the cognitive impairments in the DS group. Multiple regression analyses revealed that sustained attention and cognitive flexibility were the core impaired cognitive domains mediating other cognitive functions in DS and NDS patients respectively.ConclusionsDS patients exemplified worse in almost all cognitive domains than NDS patients. Sustained attention and cognitive flexibility might be the key impaired cognitive domains for DS and NDS patients respectively. The present study suggested the DS as a specific subgroup of schizophrenia.

Neuropsychological Profile of Specific Executive Dysfunctions in Patients with Deficit and Non-deficit Schizophrenia

“…Unfortunately, such relationships have been very rarely examined in this group of patients. Only Yu et al (2015) managed to demonstrate a significant correlation between scores on the TMT and VFT P in patients with DS. It may also be important to identify which aspects of executive function are most impaired in patients with DS and NDS.…”

Primary and persistent negative symptoms: Concepts, assessments and neurobiological bases

“…Neuropsychological investigations reported discrepant findings, with some studies reporting a greater impairment in DS than in NDS on measures of fronto-parietal functions (i.e., attention, executive control and visuospatial functions, Buchanan et al, 1994;Bryson et al, 2001;Yu et al, 2015), prefrontal functions (verbal fluency, concept formation and cognitive flexibility, Cascella et al, 2008;Polgár et al, 2010) or cortico-striatal functions (reinforcement learning, Farkas et al, 2008;Polgár et al, 2010;Vogel et al, 2013). The majority of studies (Galderisi et al, , 2013aWang et al, 2008;Polgár et al, 2008;Réthelyi et al, 2012;Fervaha et al, 2015a) and a meta-analysis (Cohen et al, 2007) reported a generalized cognitive impairment in DS vs both NDS and controls.…”

Towards a new classification of stable phase schizophrenia into major and simple neuro‐cognitive psychosis: Results of unsupervised machine learning analysis

“…Firstly, objective neurocognitive deficits in schizophrenia comprise impairments in planning, context processing, working memory, conscious recollection, attention, and visual memory deficits. [8][9][10] Using the Consortium to Establish a Registry for Alzheimer Disease (CERAD) and Cambridge Neuropsychological Test Automated Battery (CANTAB) tests, it was shown that individuals with deficit schizophrenia have more profound and a broader range of cognitive impairments than patients with nondeficit forms of the disorder, including impairments in emotional recognition, semantic and working memory, sustained attention, and especially in episodic memory, including recall and recognition. 10 Secondly, many individuals with schizophrenia experience clinically meaningful depression and anxiety symptoms.…”