A systematic review of performance-based assessment studies on cognitive biases in schizophrenia spectrum psychoses and clinical high-risk states: A summary of 40 years of research.

Cognitive models of psychosis have stimulated empirical studies on cognitive biases involved in schizophrenia spectrum psychoses and their symptoms. This systematic review aimed to summarize the studies on the role of cognitive biases as assessed in different performance-based tasks in schizophrenia spectrum psychoses and clinical high-risk states. We focused on five cognitive biases linked to psychosis, i.e., aberrant salience, attentional biases, source monitoring biases, jumping to conclusions, and bias against disconfirmatory evidence. We identified N = 324 studies published in N = 308 articles fulfilling inclusion criteria. Most studies have been cross-sectional and confirmed that the schizophrenia spectrum psychoses are related to exaggerated cognitive biases compared to healthy controls. On the contrary, less evidence suggests a higher tendency for cognitive biases in the UHR sample. The only exceptions were source monitoring and jumping to conclusions, which were confirmed to be exaggerated in both clinical groups. Hallucinations and delusions were the most frequent symptoms studied in the context of cognitive biases. Based on the findings, we presented a hypothetical model on the role of interactions between cognitive biases or additive effects of biases in shaping the risk of psychosis. Future research is warranted for further development of cognitive models for psychosis.

Managing the Burden of Dementia Related Delusions and Hallucinations.

Identify the burden experienced by patients with dementia-related delusions and hallucinations. Assess patients with dementia for the presence of delusions and hallucinations. Individualize treatment in patients with dementia-related delusions and hallucinations. Align treatment of patients with Parkinson's psychosis with current recommendations.

Violence and Suicide Risk Assessment in Youth with Psychotic Disorders: Practical Considerations for Community Clinicians.

Psychosis is a unique and significant risk factor associated with violent and suicidal behavior and warrants special consideration. This article presents a careful review of the literature on violence risk and psychosis and suicide risk and psychosis as it pertains to youth or those who have been newly diagnosed with or are at high risk for psychotic disorders. Each topic is covered in reference to general considerations and specific psychotic symptoms (eg, hallucinations, delusions, paranoia). The reader can refer to practical boxes to assist in identifying relevant risk factors and examples of questions to ask the patient and family.

The Nose Knows or Does it? Olfactory Reference Syndrome in Patients Presenting for Assessment of Unusual Body Odor.

Olfactory reference syndrome (ORS) is a rarely diagnosed psychiatric disorder in which individuals falsely believe that they emit an offensive body odor. This retrospective cohort study characterizes the clinical and demographic features of 54 individuals who presented to a Canadian genetics clinic for query trimethylaminuria (TMAU), an inherited disorder in which a pungent fishy odor is produced. The majority (83%) were found to have a likely diagnosis of ORS and a high rate (73.3%) of concomitant psychiatric disorders; only two patients were diagnosed with TMAU. This study highlights the genetics clinic as an unexpected and major ascertainment point for ORS, and shows that ORS can be differentiated from TMAU by age of onset (~28 years), odor characterization (refuse-related), and the presence of associated comorbid psychiatric diagnoses. There is a low diagnostic rate of ORS, attesting to the need for improved education and awareness.

Delusions, anger, and serious violence: new findings from the MacArthur Violence Risk Assessment Study.

INTRODUCTION: Recent research on the association between delusions and violence has suggested complex and differing pathways. Furthermore, it has been emphasized that temporal proximity is fundamental when investigating these relationships. We reanalyzed data from the MacArthur Violence Risk Assessment Study utilizing a different methodological approach to investigate associations between specific delusions and violence. METHODS: Longitudinal study of 1136 male and female civil psychiatric inpatients after discharge. Delusions, affect due to delusions, and violence were measured at baseline and in 5 follow-up assessments. Serious violence was established using the MacArthur Community Violence Interview. Logistic mixed-effect models for repeated measures were performed. RESULTS: A "prospective" model confirmed previous findings that delusions do not predict later violence. However, reanalysis, considering temporal proximity, indicated a relationship between specific delusions and outcome including: being spied upon (adjusted OR [AOR] = 1.62, 95% CI = 1.06-2.47, P = .027), being followed (AOR = 1.90, 95% CI = 1.29-2.80, P = .001), being plotted against (AOR = 1.70, 95% CI = 1.14-2.52, P = .009), being under control of person/force (AOR = 1.92, 95% CI = 1.24-2.97, P = .003), thought insertion (AOR = 1.63, 95% CI = 1.00-2.66, P = .048), and having special gifts/powers (AOR = 1.95, 95% CI = 1.31-2.92, P = .001). All these delusions were associated with angry affect (P < .05). Inclusion of anger in the model significantly attenuated the main effects (except grandiose delusions), indicating an indirect pathway. CONCLUSIONS: Temporal proximity is crucial when investigating relationships between delusions and violence. Anger due to delusions is the key factor in this pathway. Our findings have important implications for identification of psychotic patients at risk for violent behavior and, most importantly, management of their risk.

Content of delusional thoughts in Alzheimer's disease and assessment of content-specific brain dysfunctions with BEHAVE-AD-FW and SPECT.

BACKGROUND: A consensus on the brain dysfunction(s) underlying the delusions of Alzheimer's Dementia (AD) remains to be achieved. The aim of the present study was to test the hypothesis that content-based categorization of delusional ideas manifests as dysfunction of category-specific brain regions. METHODS: Fifty-nine consecutive first-visit AD outpatients underwent Single Photon Emission Computed Tomography (SPECT), Mini-Mental State Examination, and Behavioral Pathology in Alzheimer's Disease Frequency-Weighted Severity scale (BEHAVE-AD-FW) to assess cerebral blood flow (CBF), cognitive function, and delusion, respectively. SPECT images were analyzed by SPM5. RESULTS: CBF decreased at the temporal poles and right inferior temporal gyrus in "delusion of theft," at the temporal poles in "suspiciousness/paranoia," at the right parahippocampal gyrus and insula in "abandonment," and at the right amygdala in "Residence is not home." CONCLUSIONS: Our findings offer a perspective on the discrete categories of the pathological thoughts of AD patients that have previously been lumped together as "delusions." Dysfunction of the temporal poles may be associated with a socioemotional deterioration that may include pathological suspiciousness. Delusion of theft may be a manifestation of socioemotional deterioration and poor insight. Emotional factors may be essential for delusions of abandonment and "not home."

Correlation between a reduction in Frontal Assessment Battery scores and delusional thoughts in patients with Alzheimer's disease.

AIMS: The purpose of the present study was to investigate the relationship between delusional thoughts (delusional ideation or misidentification) and frontal lobe function using the Japanese version of the Frontal Assessment Battery (FAB) bedside screening neuropsychological test in early stage Alzheimer's disease (AD) patients. METHODS: Forty-eight probable AD patients with Mini-Mental State Examination score >or=18 points and a clinical dementia rating score of either 0.5 or 1.0 were divided into two groups based on data obtained from interviews with their caregivers: a delusional thought group (n = 19) and a non-delusional thought group (n = 29). The FAB total and subtest scores were then compared for the two groups. RESULTS: Significant differences were found between the FAB total (P < 0.01) and subtest scores (similarities, motor series, conflicting instructions; P < 0.05) for the two groups. Multiple regression analysis showed that delusional thought was significantly associated with the FAB total score. CONCLUSIONS: In addition to episodic memory disorders, a reduction in the FAB score may reflect frontal lobe dysfunctions, including executive function, in patients with AD, leading to delusional ideation.

Beliefs, mental health, and evolutionary threat assessment systems in the brain.

This article reviews aspects of the literature on neuroscience, psychiatry, and cognitive and evolutionary psychology to illustrate how primitive brain mechanisms that evolved to assess environmental threats underlie psychiatric disorders, and how beliefs can affect psychiatric symptoms through these brain systems. Psychiatric theories are discussed that (a) link psychiatric disorders to threat assessment and (b) explain how the normal functioning of threat assessment systems can become pathological. Three brain structures that are consistently implicated in psychiatric symptomology also are involved in threat assessment and self-defense: the prefrontal cortex, the basal ganglia, and parts of the so-called limbic system. We propose that as these structures evolved over time they formed what we refer to as evolutionary threat assessment systems, which detect and assess potential threats of harm. Drawing on various psychological and psychiatric theories we propose how beliefs about the world can moderate psychiatric symptoms through their influence on evolutionary threat assessment systems.