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Biological Psychiatry Nov 2018Fueled by developments in computational neuroscience, there has been increasing interest in the underlying neurocomputational mechanisms of psychosis. One successful... (Review)
Review
Fueled by developments in computational neuroscience, there has been increasing interest in the underlying neurocomputational mechanisms of psychosis. One successful approach involves predictive coding and Bayesian inference. Here, inferences regarding the current state of the world are made by combining prior beliefs with incoming sensory signals. Mismatches between prior beliefs and incoming signals constitute prediction errors that drive new learning. Psychosis has been suggested to result from a decreased precision in the encoding of prior beliefs relative to the sensory data, thereby garnering maladaptive inferences. Here, we review the current evidence for aberrant predictive coding and discuss challenges for this canonical predictive coding account of psychosis. For example, hallucinations and delusions may relate to distinct alterations in predictive coding, despite their common co-occurrence. More broadly, some studies implicate weakened prior beliefs in psychosis, and others find stronger priors. These challenges might be answered with a more nuanced view of predictive coding. Different priors may be specified for different sensory modalities and their integration, and deficits in each modality need not be uniform. Furthermore, hierarchical organization may be critical. Altered processes at lower levels of a hierarchy need not be linearly related to processes at higher levels (and vice versa). Finally, canonical theories do not highlight active inference-the process through which the effects of our actions on our sensations are anticipated and minimized. It is possible that conflicting findings might be reconciled by considering these complexities, portending a framework for psychosis more equipped to deal with its many manifestations.
Topics: Bayes Theorem; Delusions; Hallucinations; Humans; Psychotic Disorders
PubMed: 30007575
DOI: 10.1016/j.biopsych.2018.05.015 -
Ugeskrift For Laeger Feb 2017Body dysmorphic disorder is defined by a preoccupation of one or more non-existent or slight defects or flaws in the physical appearance. The prevalence is 1.7-2.4% in... (Review)
Review
Body dysmorphic disorder is defined by a preoccupation of one or more non-existent or slight defects or flaws in the physical appearance. The prevalence is 1.7-2.4% in the general population with a higher incidence rate in women. The rate of suicidal ideation is as high as 80%, and up to 25% of the patients attempt to commit suicide. Comorbidities, such as obsessive compulsive disorder, depression, and anxiety, are frequent. These patients may seek cosmetic or dermatologic rather than psychological treatment. In the view of the high prevalence and risk of suicide, recognizing this disorder is important.
Topics: Body Dysmorphic Disorders; Delusions; Female; Humans; Male; Mental Disorders; Obsessive-Compulsive Disorder; Phobia, Social; Suicidal Ideation; Suicide, Attempted; Surgery, Plastic
PubMed: 28397684
DOI: No ID Found -
Comprehensive Psychiatry Apr 2021Two of Europe's most influential psychopathologists at the start of the twentieth century (Eugen Bleuler and Karl Jaspers) pointed out the fact that patients rarely act... (Review)
Review
OBJECTIVES
Two of Europe's most influential psychopathologists at the start of the twentieth century (Eugen Bleuler and Karl Jaspers) pointed out the fact that patients rarely act according to their delusions. This study proposes an investigation of how this issue is addressed in psychopathological literature.
METHODS
This article offers a critical review of psychopathological literature which focuses on the influence of delusional ideation on behaviour.
RESULTS
Phenomenological psychiatry has relied on the paradox pointed out by Bleuler and Jaspers to emphasize disorders of self-experience in psychosis whereas analytical philosophy of delusion has focused on the psychological status of delusion, regarded as belief, certainty, or imagination. The empirical studies conducted during the past three decades - which were devoted to acting on delusion - focused on violent and safety-seeking behaviours. These studies have shown that these behavioural disorders are motivated by an emotional outburst (anger and/or fear) rather than by delusional content.
CONCLUSION
Delusional inconsequentiality can be clarified by conceptual research in phenomenological psychiatry and analytical philosophy, even though its role in the psychopathological processes has not yet been clearly identified or conceptualised. Empirical psychopathology on acting on delusion confirms the delusional inconsequentiality, but only implicitly, by highlighting the role of affectivity (rather than beliefs) in delusional actions. Given the major implications of better understanding this phenomenon, in terms of psychopathology and clinical practices, we suggest considering delusional inconsequentiality as a promising concept which could guide further research in contemporary psychopathology.
Topics: Delusions; Humans; Psychiatry; Psychopathology; Psychotic Disorders; Thinking
PubMed: 33581447
DOI: 10.1016/j.comppsych.2021.152230 -
CMAJ : Canadian Medical Association... Aug 2019
Topics: Brain; Capgras Syndrome; Delusions; Humans; Neuropsychological Tests
PubMed: 31387959
DOI: 10.1503/cmaj.190048 -
Respiration; International Review of... 2022Rates of antimicrobial resistance are increasing globally while the pipeline of new antibiotics is drying up, putting patients with disease caused by drug-resistant... (Review)
Review
Rates of antimicrobial resistance are increasing globally while the pipeline of new antibiotics is drying up, putting patients with disease caused by drug-resistant bacteria at increased risk of complications and death. The growing costs for diagnosis and management of drug resistance threaten tuberculosis control where the disease is endemic and resources limited. Bacteriophages are viruses that attack bacteria. Phage preparations served as anti-infective agents long before antibiotics were discovered. Though small in size, phages are the most abundant and diverse biological entity on earth. Phages have co-evolved with their hosts and possess all the tools needed to infect and kill bacteria, independent of drug resistance. Modern biotechnology has improved our understanding of the biology of phages and their possible uses. Phage preparations are available to treat meat, fruit, vegetables, and dairy products against parasites or to prevent contamination with human pathogens, such as Listeria monocytogenes, Escherichia coli, or Staphylococcus aureus. Such phage-treated products are considered fit for human consumption. A number of recent case reports describe in great detail the successful treatment of highly drug-resistant infections with individualized phage preparations. Formal clinical trials with standardized products are slowly emerging. With its highly conserved genome and relative paucity of natural phage defence mechanisms Mycobacterium tuberculosis appears to be a suitable target for phage treatment. A phage cocktail with diverse and strictly lytic phages that kill all lineages of M. tuberculosis, and can be propagated on Mycobacterium smegmatis, has been assembled and is available for the evaluation of optimal dosage and suitable routes of administration for tuberculosis in humans. Phage treatment can be expected to be safe and active on extracellular organisms, but phage penetration to intracellular and granulomatous environments as well as synergistic effects with antibiotics are important questions to address during further evaluation.
Topics: Anti-Bacterial Agents; Bacteriophages; Delusions; Humans; Mycobacteriophages; Mycobacterium tuberculosis; Tuberculosis
PubMed: 34814151
DOI: 10.1159/000519870 -
Consciousness and Cognition May 2015Delusions are defined as irrational beliefs that compromise good functioning. However, in the empirical literature, delusions have been found to have some psychological... (Review)
Review
Delusions are defined as irrational beliefs that compromise good functioning. However, in the empirical literature, delusions have been found to have some psychological benefits. One proposal is that some delusions defuse negative emotions and protect one from low self-esteem by allowing motivational influences on belief formation. In this paper I focus on delusions that have been construed as playing a defensive function (motivated delusions) and argue that some of their psychological benefits can convert into epistemic ones. Notwithstanding their epistemic costs, motivated delusions also have potential epistemic benefits for agents who have faced adversities, undergone physical or psychological trauma, or are subject to negative emotions and low self-esteem. To account for the epistemic status of motivated delusions, costly and beneficial at the same time, I introduce the notion of epistemic innocence. A delusion is epistemically innocent when adopting it delivers a significant epistemic benefit, and the benefit could not be attained if the delusion were not adopted. The analysis leads to a novel account of the status of delusions by inviting a reflection on the relationship between psychological and epistemic benefits.
Topics: Defense Mechanisms; Delusions; Humans; Knowledge; Motivation
PubMed: 25459652
DOI: 10.1016/j.concog.2014.10.005 -
Psychiatrike = Psychiatriki 2018The Delusional Misidentification Syndromes (DMSs) are characterized by defective integration of the normally The Delusional Misidentification Syndromes (DMSs) are...
The Delusional Misidentification Syndromes (DMSs) are characterized by defective integration of the normally The Delusional Misidentification Syndromes (DMSs) are characterized by defective integration of the normally fused functions of perception and recognition. The classical sub-types are: the syndromes of Capgras, Fregoli,Intermetamorphosis (mentioned in 3) and Subjective doubles. These syndromes occur in a clear sensorium and shouldbe differentiated from the banal transient misidentifications occurring in confusional states and in mania and from thenon-delusional misidentifications (e.g. prosopagnosia). Joseph Capgras, who described the best-known sub-type, was indecisive on its pathogenesis. In his original report he defined the syndrome as "agnosia of identification" produced by a conflict between affective accompaniments ofsensory and mnemonic images. In his subsequent two publications, he considered the syndrome as a restitution delusionand as a psychopathological mechanism to hide incestuous desires. For more details see the chapter by J.P. Luaute in avolume on DMS. Psychodynamic approaches are, essentially, variants of the formulation that DMSs result from ambivalent feelings resolvedby directing hate feelings onto an imagined double in order to retain the original intact (and thus avoid guilt).These views have been voiced by David Enoch [relevant chapter in (3)] and with variations by many other investigatorsreviewed by Oyebode. Regression to archaic modes of thought (like thinking in terms of doubles and dualisms) due to personality disintegrationproduced by psychotic illness is a fascinating hypothesis by John Todd [mentioned in (1)]. However, if this was thecase, DMS should be much more frequent. Mayer-Gross and Ackner (mentioned in 9) had observed that when there is a delusional development, depersonalization-derealization experiences tend to be included within the delusional system. Such experiences usually precede orcoincide with the onset of DMS. In view of this, Christodoulou suggested that DMSs may represent delusional evolutions of depersonalization-derealization experiences. Similar mechanisms were proposed for false memories of familiarity,reduplicative paramnesia and autoscopy. Cerebral "dysrhythmia" has also been noted in patients with DMS. In view of clinical and prognostic similarities of DMSpatients with patients suffering from psychotic states occurring in an epileptic setting, many of these patients have beenconsidered as suffering from broadly speaking "epileptic" psychoses. Joseph [mentioned in (6)] suggested that organiccauses produce disconnection between right and left cortical areas that decode afferent sensory information. This resultsin the creation of a separate image in each hemisphere leading to an awareness of two, physically identical images. Ellis and Young [mentioned in (1) and (6)] have maintained that DMS may result from defects at different stages of aninformation processing chain. More specifically, the Capgras Syndrome appears when the route for unconscious recognitionis damaged. Similar mechanisms have been proposed for the rest of the subtypes. Margariti and Kontaxakis8 have considered that in DMS there is disruption of the ability to recognize identities ratherthan superficial appearance. Others have maintained that DMSs are multimodal neuropathologies and cannot be linkedto a single cognitive defect. Lastly, in view of the marked organic abnormalities detected in all DMS subtypes, DMSs have been linked with a greatnumber of organic conditions [reviewed in detail by Oyebode (5)]. According to Greek mythology, Procrustes was a bandit who stretched or amputated the limbs of his guests to fit hisiron bed. The DMSs do not deserve such treatment. Submitting them to the procrustean bed of uniformity should be avoided. People develop DMS for a variety of reasons. Most subjects have right hemisphere dysfunction but not exclusively.Their condition is associated not with one but with diverse phenomena (depersonalization - derealization, prosopagnosia,false memories of familiarity, autoscopy, reduplicative paramnesia etc.) similarities with psychotic phenomena associatedwith epilepsy have been suggested but this refers to some patients only. Additionally, the charged emotionalrelationship of the patient with the misidentified person(s) is neither necessary nor sufficient. Diagnostically speaking, many roads lead to DMS, ranging from the monosymptomatic and monothematic one (consideredas par excellence DMS) to that associated with disorders mainly of the schizophrenic or organic spectrum. DMScan also be reached by a more "superficial" road, the one of depression, in which the delusion is secondary and often dependenton the self-depreciation ideation. Speculating on these syndromes is a fascinating journey in psychopathologybut, although in most cases an organic contributor is present, yet the great diversity of conditions in the setting of whichDMSs occur renders the possibility of a unifying hypothesis unlikely.
Topics: Cognition Disorders; Delusions; Humans; Neuropsychological Tests; Psychotherapy, Psychodynamic; Schizophrenia, Paranoid
PubMed: 29754115
DOI: 10.22365/jpsych.2018.291.15 -
Psychiatrike = Psychiatriki Dec 2023We read with interest the recent report on the definition, diagnosis, and clinical implications of religious delusions (RD).1 In our sample of 929 delusional...
We read with interest the recent report on the definition, diagnosis, and clinical implications of religious delusions (RD).1 In our sample of 929 delusional schizophrenia patients who had been admitted to two psychiatric hospitals in Germany between 2010 and 2014, 138 patients (15%) reported RD. In 569 cases, information on religious affiliation was available. Patients with religious affiliation did not differ from patients without religious affiliation in the frequency of RD [χ2(1,569)= 0.02, p= 0.885]. Furthermore, patients with RD did not differ from patients with other types of delusion (OD) in the duration of hospitalisation [t(924)= -0.39, p= 0.695], or the number of hospitalisations [t(927)= -0.92, p= 0.358]. Additionally, in 185 cases, information on Clinical Global Impressions (CGI) and Global Assessment of Functioning (GAF) was available at the beginning and end of the hospital stay. By CGI-scores, no difference was seen in morbidity of subjects with RD relative to subjects with OD on admission [t(183)= -0.78, p= 0.437] and discharge t(183)= -1.10, p= .273 . Likewise, GAF-scores on admission did not differ in these groups [t(183)= 1.50, p= 0.135]. However, a trend was noted for lower GAF-scores on discharge in subjects with RD [t(183)= 1.91, p= .057, d= 0.39, CI 95% (-0.12-0.78)]. While RD have often been associated with a poorer prognosis in schizophrenia,2,3 we argue that this need not apply to all domains. Mohr et al4 reported that patients with RD were less likely to maintain psychiatric treatment, but did not have a more severe clinical status than patients with OD. Iyassu et al5 found higher levels of positive, but also lower levels of negative symptoms in patients with RD compared to patients with OD. Groups did not differ in terms of length of illness or level of medication. Siddle et al6 reported higher symptom scores in patients with RD at their first presentation, but a similar response to treatment when compared to patients with OD after 4 weeks of treatment. Furthermore, Ellersgaard et al7 iindicated that first-episode psychosis patients with RD at baseline were more likely to be non-delusional at follow-ups conducted after years 1, 2 and 5 when compared to patients with OD at baseline. We conclude that RD may thus interfere with short-term clinical outcome. With regard to long-term effects more favourable observations exist8 and the interplay of psychotic delusions with non-psychotic beliefs still warrants further research.
Topics: Humans; Delusions; Psychotic Disorders; Schizophrenia; Hospitalization
PubMed: 37212804
DOI: 10.22365/jpsych.2023.012 -
Psychiatria Polska Oct 2018Jealousy is defined as a complex mental state caused by a real or false - imaginary - change in a way of perception of a threat of terminating a valued partnership in... (Review)
Review
Jealousy is defined as a complex mental state caused by a real or false - imaginary - change in a way of perception of a threat of terminating a valued partnership in favor of a real or imaginary rival. Apart from jealousy demonstrated by mentally disordered people, but without symptoms of mental illness and obsessive jealousy, there is also a psychotic jealousy. One of diagnostic difficulties is to determine when a normal jealousy about a partner acquires delusional nature and the boundary between these two can be difficult to detect, which often is a concern of forensic psychiatrists. A mistake in diagnosis can seriously affect issuing of opinions and can have legal consequences. There are accounts claiming that the emergence of delusional jealousy is a continuous process, from the so-called normal to morbid jealousy. Diagnostic assessments in this matter bring difficulties in juidicial-psychiatric assessments. Delusions of marriage infidelity accompany various psychotic disorders and their foundations can be found in endogenous factors, organic changes in peripheral nervous system and addictions. People demonstrating these types of delusional disorders are extremely dangerous for the environment, not solely because of the presence of psychotic symptoms, but also because of various environmental and relationship-related factors, which contribute to the genesis of their criminal offenses. Making accurate and just forensic psychiatric assessment of this group of offenders concerns risk assessment of offenders, validity of the use of security measures and the type of therapeutic interventions.
Topics: Adult; Dangerous Behavior; Delusions; Female; Forensic Psychiatry; Humans; Jealousy; Male; Psychotic Disorders; Spouses
PubMed: 30584822
DOI: 10.12740/PP/OnlineFirst/79840 -
Canadian Journal of Psychiatry. Revue... Mar 2017Neuropsychiatric symptoms (NPS) may be the first manifestation of an underlying neurocognitive disorder. We undertook a review to provide an update on the epidemiology... (Review)
Review
OBJECTIVE
Neuropsychiatric symptoms (NPS) may be the first manifestation of an underlying neurocognitive disorder. We undertook a review to provide an update on the epidemiology and etiological mechanisms of NPS that occur in mild cognitive impairment (MCI) and just before the onset of MCI. We discuss common clinical presentations and the implications for diagnosis and care.
METHOD
The authors conducted a selective review of the literature regarding the emergence of NPS in late life, before and after the onset of MCI. We discuss recent publications that explore the epidemiology and etiological mechanisms of NPS in the earliest clinical stages of these disorders.
RESULTS
NPS have been reported in 35% to 85% of adults with MCI and also occur in advance of cognitive decline. The occurrence of NPS for the first time in later life should increase suspicion for an underlying neurocognitive disorder. The presenting symptom may provide a clue regarding the etiology of the underlying disorder, and the co-occurrence of NPS may herald a more accelerated cognitive decline.
CONCLUSIONS
NPS are prevalent in the early clinical stages of neurocognitive disorders and can serve as both useful diagnostic and prognostic indicators. Recognition of NPS as early manifestations of neurocognitive disorders will become increasingly important as we move towards preventative strategies and disease-modifying treatments that may be most effective when deployed in the earliest stages of disease.
Topics: Anxiety; Apathy; Cognitive Dysfunction; Delusions; Depression; Hallucinations; Humans; Psychomotor Agitation; Social Behavior Disorders
PubMed: 28212495
DOI: 10.1177/0706743716648296