A Review of Neuropsychological Differences Between Paranoid and Nonparanoid Schizophrenia Patients

Zalewski, Christine; Johnson-Selfridge, Margaret T.; Ohriner, Steven; Zarrella, Karen; Seltzer, James C.

doi:10.1093/oxfordjournals.schbul.a033305

Cited by 55 publications

(37 citation statements)

References 104 publications

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“…Although in the present study the mean onset of the disease did not differ between the paranoid and nonparanoid group, several lines of evidence support that the paranoid subtype of SCZ is associated with later disease onset and better prognosis (McGlashan and Fenton, 1991;Zalewski et al, 1998). A connection between an abnormality in the endocannabinoid system and paranoid SCZ has been reported.…”

Section: Disease-related Effectscontrasting

confidence: 66%

Paranoid Schizophrenia is Characterized by Increased CB1 Receptor Binding in the Dorsolateral Prefrontal Cortex

Dalton

Long

Weickert

et al. 2011

Neuropsychopharmacol

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A number of studies suggest a dysregulation of the endogenous cannabinoid system in schizophrenia (SCZ). In the present study, we examined cannabinoid CB 1 receptor (CB 1 R) binding and mRNA expression in the dorsolateral prefrontal cortex (DLPFC) (Brodmann's area 46) of SCZ patients and controls, post-mortem. Receptor density was investigated using autoradiography with the CB 1 R ligand [ 3 H] CP 55 940 and CB 1 R mRNA expression was measured using quantitative RT-PCR in a cohort of 16 patients with paranoid SCZ, 21 patients with non-paranoid SCZ and 37 controls matched for age, post-mortem interval and pH. All cases were obtained from the University of Sydney Tissue Resource Centre. Results were analyzed using one-way analysis of variance (ANOVA) and post hoc Bonferroni tests and with analysis of covariance (ANCOVA) to control for demographic factors that would potentially influence CB 1 R expression. There was a main effect of diagnosis on [ 3 H] CP 55 940 binding quantified across all layers of the DLPFC (F(2,71) ¼ 3.740, p ¼ 0.029). Post hoc tests indicated that this main effect was due to patients with paranoid SCZ having 22% higher levels of CB 1 R binding compared with the control group. When ANCOVA was employed, this effect was strengthened (F(2,67) ¼ 6.048, p ¼ 0.004) with paranoid SCZ patients differing significantly from the control (p ¼ 0.004) and from the non-paranoid group (p ¼ 0.016). In contrast, no significant differences were observed in mRNA expression between the different disease subtypes and the control group. Our findings confirm the existence of a CB 1 R dysregulation in SCZ and underline the need for further investigation of the role of this receptor particularly in those diagnosed with paranoid SCZ.

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Section: Disease-related Effectscontrasting

confidence: 66%

Paranoid Schizophrenia is Characterized by Increased CB1 Receptor Binding in the Dorsolateral Prefrontal Cortex

Dalton

Long

Weickert

et al. 2011

Neuropsychopharmacol

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“…Regardless, these findings are consistent with previous literature indicating that paranoid patients have fewer cognitive impairments, respond better to treatment, and display better overall prognosis. On the other hand, negative or deficit patients display more cognitive impairments, are less responsive to treatment, and have a worse overall prognosis (Fenton & McGlashan, 1994;Hill et al, 2001;Kaplan & Sadock, 1994;Kirkpatrick, 1997;Zalewski et al, 1998).…”

Section: Discussionmentioning

confidence: 99%

Neuropsychological Profiles Delineate Distinct Profiles of Schizophrenia, an Interaction Between Memory and Executive Function, and Uneven Distribution of Clinical Subtypes

Hill¹,

Ragland²,

Gur³

et al. 2002

Journal of Clinical and Experimental Neuropsychology

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Neuropsychological performance in 151 patients with schizophrenia was examined using cluster analysis to identify neurocognitive subtypes. Hierarchical and iterative partitioning methods identified four clusters using an extended neuropsychological battery. Consistent with previous findings two extreme clusters were characterized by near normative performance and profound global dysfunction, respectively. The two remaining neurocognitive clusters displayed moderatesevere dysfunction and were differentiated by unique patterns of abstraction and flexibility, attention, spatial memory, and sensory-perception. Analysis of variance revealed an interaction between global memory and executive function for clusters III and IV. Although limited cluster differences were found relative to clinical and historical data, the distribution of previously defined clinical subtypes was uneven among neurocognitive clusters. Paranoid patients were significantly more likely to be classified into cluster II and disproportionately absent from clusters I and IV. Patients with negative and disorganized clinical subtypes comprised a disproportionate component of clusters I and IV but were less likely to be classified in cluster II. This suggests greater correspondence than previously postulated between systems responsible for clinical symptomatology and those moderating neurocognitive dysfunction.Heterogeneity of schizophrenia has long been an area of theoretical and empirical inquiry. Numerous attempts have been made to classify the disorder into meaningful subtypes. Several classification systems based on clinical symptomatology have been proposed with the goal of identifying distinct etiology. Despite advances in subtyping and understanding clinical and cognitive symptomatology, heterogeneity in schizophrenia remains troublesome for investigators. Kraepelin (1925) and Bleuler (1952) initially suggested four subtypes including simple, catatonic, hebephrenic, and paranoid. Subsequent clinical classification systems focused on paranoid/nonparanoid, deficit/nondeficit, and positive/negative (Bilder, Mukherjee, Rieder, & Pandurangi, 1985;Carpenter, Bartko, Carpenter, & Strauss, 1976;Liddle, 1987) and a recent meta-analysis found three subtypes to be the most stable (positive, negative, and disorganized;Grube, Bilder, & Goldman, 1998). However, classification systems based on clinical phenomenology have been criticized on both methodological and theoretical grounds (Andreasen, Flaum, Schultz, Duyurek, & Miller, 1997;Goldberg & Weinberger, 1995). Specific criticisms included instability of clinical classification over time, reliance on self-report measures, and use of rating scales that require subjective interpretation. Moreover, growing understanding of schizophrenia as a neurocognitive disorder has focused attention on neural system involvement. One difficulty with subtypes based on clinical phenomenology is the difficulty relating symptoms directly to neural mechanisms. NIH Public AccessStudies of the relationship between clinic...

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“…More recent neuropsychological studies show that subjects with 'pure' delusions tend not to show any severe neuropsychological dysfunctions. Reviewing more than 32 neuropsychological articels, Zalewski et al [55] found no great differences in cognitive performance between paranoid and non-paranoid schizophrenics. Furthermore, neuropsychological data are scarce for non-schizophrenic delusional patients, mainly because the disorder is rare and because patients usually do not see themselves as such, and so do not seek medical help or participate in scientific studies.…”

Section: Neuropsychological Findingsmentioning

confidence: 99%

Theories of Delusional Disorders

2007

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Delusional syndromes can occur in a number of psychiatric, neurological or other disorders. They can also be caused by neurotoxic agents (e.g., heavy metals) as well as substance addiction. There are several hypotheses on the underlying cognitive or emotional processes associated with organic factors of delusional disorders, depending on the patient groups examined and the methods used. The aim of this paper is to provide a comprehensive review and critical assessment of the various, rather heterogeneous theories in this field.

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A Review of Neuropsychological Differences Between Paranoid and Nonparanoid Schizophrenia Patients

Cited by 55 publications

References 104 publications

Paranoid Schizophrenia is Characterized by Increased CB1 Receptor Binding in the Dorsolateral Prefrontal Cortex

Paranoid Schizophrenia is Characterized by Increased CB1 Receptor Binding in the Dorsolateral Prefrontal Cortex

Neuropsychological Profiles Delineate Distinct Profiles of Schizophrenia, an Interaction Between Memory and Executive Function, and Uneven Distribution of Clinical Subtypes

Theories of Delusional Disorders

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