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Journal of Child Psychology and... Jul 2023Psychotic symptoms, including hallucinations, delusions, and disorganized thinking and behaviors, are the hallmarks of schizophrenia; but may also present in the context... (Review)
Review
Psychotic symptoms, including hallucinations, delusions, and disorganized thinking and behaviors, are the hallmarks of schizophrenia; but may also present in the context of other psychiatric and medical conditions. Many children and adolescents describe psychotic-like experiences, which can be associated with other types of psychopathology and past experiences (e.g., trauma, substance use, and suicidality). However, most youth reporting such experiences do not have, nor will ever develop, schizophrenia or another psychotic disorder. Accurate assessment is critical because these different presentations have different diagnostic and treatment implications. For this review, we focus primarily on the diagnosis and treatment of early onset schizophrenia. In addition, we review the development of community-based first-episode psychosis programming, and the importance of early intervention and coordinated care.
Topics: Adolescent; Child; Humans; Psychotic Disorders; Schizophrenia; Hallucinations; Suicidal Ideation; Psychopathology; Delusions
PubMed: 36878476
DOI: 10.1111/jcpp.13777 -
Neuroscience and Biobehavioral Reviews Jul 2023Despite decades of research, we do not definitively know how people sometimes see things that are not there. Eight models of complex visual hallucinations have been... (Review)
Review
Despite decades of research, we do not definitively know how people sometimes see things that are not there. Eight models of complex visual hallucinations have been published since 2000, including Deafferentation, Reality Monitoring, Perception and Attention Deficit, Activation, Input, and Modulation, Hodological, Attentional Networks, Active Inference, and Thalamocortical Dysrhythmia Default Mode Network Decoupling. Each was derived from different understandings of brain organisation. To reduce this variability, representatives from each research group agreed an integrated Visual Hallucination Framework that is consistent with current theories of veridical and hallucinatory vision. The Framework delineates cognitive systems relevant to hallucinations. It allows a systematic, consistent, investigation of relationships between the phenomenology of visual hallucinations and changes in underpinning cognitive structures. The episodic nature of hallucinations highlights separate factors associated with the onset, persistence, and end of specific hallucinations suggesting a complex relationship between state and trait markers of hallucination risk. In addition to a harmonised interpretation of existing evidence, the Framework highlights new avenues of research, and potentially, new approaches to treating distressing hallucinations.
Topics: Humans; Hallucinations; Brain; Attention Deficit Disorder with Hyperactivity
PubMed: 37141962
DOI: 10.1016/j.neubiorev.2023.105208 -
Brain : a Journal of Neurology Apr 2021Although psychosis is a defining feature of Lewy body disease, psychotic symptoms occur in a subset of patients with every major neurodegenerative disease. Few studies,...
Although psychosis is a defining feature of Lewy body disease, psychotic symptoms occur in a subset of patients with every major neurodegenerative disease. Few studies, however, have compared disease-related rates of psychosis prevalence in a large autopsy-based cohort, and it remains unclear how diseases differ with respect to the nature or content of the psychosis. We conducted a retrospective chart review of 372 patients with autopsy-confirmed neurodegenerative pathology: 111 with Alzheimer's disease, 59 with Lewy body disease and concomitant Alzheimer's disease, 133 with frontotemporal lobar degeneration (FTLD) with tau inclusions (including progressive supranuclear palsy, corticobasal degeneration or Pick's disease), and 69 with FTLD and TDP inclusions (FTLD-TDP, including types A-C). Psychosis content was classified by subtype, and the frequency of each subtype was compared among pathological diagnoses using logistic regression. A total of 111 of 372 patients had psychosis. Compared to other groups, patients with Lewy body disease/Alzheimer's disease pathology were significantly more likely to have hallucinations and were more likely to have more than one subtype of hallucination. Patients with Braak Parkinson stage 5-6 Lewy body disease were significantly more likely than those with no Lewy body disease to have visual hallucinations of misperception, peripheral hallucinations, hallucinations that moved, hallucinations of people/animals/objects, as well as delusions regarding a place and delusions of misidentification. The feeling of a presence occurred significantly more frequently in patients with Lewy body disease/Alzheimer's disease than all other pathologies. Patients with FTLD-TDP were significantly more likely to have delusions, and for the delusions to occur in the first 3 years of the disease, when compared to patients with Alzheimer's disease and FTLD-tau, though rates were not significantly greater than patients with Lewy body disease/Alzheimer's disease. Paranoia occurred more frequently in the FTLD-TDP and Lewy body disease/Alzheimer's disease categories compared to patients with Alzheimer's disease or FTLD-tau. Patients with FTLD-TDP pathology had delusions of misidentification as frequently as patients with Lewy body disease/Alzheimer's disease, and were significantly more likely to have self-elevating delusions such as grandiosity and erotomania compared to patients with other pathologies including FTLD-tau. These data show that the nature and content of psychosis can provide meaningful information about the underlying neurodegenerative pathology, emphasizing the importance of characterizing patients' psychoses for prediction of the neuropathological diagnosis, regardless of a patient's clinical syndrome.
Topics: Aged; Delusions; Female; Hallucinations; Humans; Male; Middle Aged; Neurodegenerative Diseases; Prevalence; Psychotic Disorders
PubMed: 33501939
DOI: 10.1093/brain/awaa413 -
Schizophrenia Bulletin Jan 2017Hallucinations constitute one of the 5 symptom domains of psychotic disorders in DSM-5, suggesting diagnostic significance for that group of disorders. Although specific... (Review)
Review
Hallucinations constitute one of the 5 symptom domains of psychotic disorders in DSM-5, suggesting diagnostic significance for that group of disorders. Although specific featural properties of hallucinations (negative voices, talking in the third person, and location in external space) are no longer highlighted in DSM, there is likely a residual assumption that hallucinations in schizophrenia can be identified based on these candidate features. We investigated whether certain featural properties of hallucinations are specifically indicative of schizophrenia by conducting a systematic review of studies showing direct comparisons of the featural and clinical characteristics of (auditory and visual) hallucinations among 2 or more population groups (one of which included schizophrenia). A total of 43 articles were reviewed, which included hallucinations in 4 major groups (nonclinical groups, drug- and alcohol-related conditions, medical and neurological conditions, and psychiatric disorders). The results showed that no single hallucination feature or characteristic uniquely indicated a diagnosis of schizophrenia, with the sole exception of an age of onset in late adolescence. Among the 21 features of hallucinations in schizophrenia considered here, 95% were shared with other psychiatric disorders, 85% with medical/neurological conditions, 66% with drugs and alcohol conditions, and 52% with the nonclinical groups. Additional differences rendered the nonclinical groups somewhat distinctive from clinical disorders. Overall, when considering hallucinations, it is inadvisable to give weight to the presence of any featural properties alone in making a schizophrenia diagnosis. It is more important to focus instead on the co-occurrence of other symptoms and the value of hallucinations as an indicator of vulnerability.
Topics: Hallucinations; Humans; Schizophrenia
PubMed: 27872259
DOI: 10.1093/schbul/sbw132 -
Frontiers in Bioscience (Landmark... Jan 2021Synesthesia literally means a "union of the senses" whereby two or more of the five senses that are normally experienced separately are involuntarily and automatically... (Review)
Review
Synesthesia literally means a "union of the senses" whereby two or more of the five senses that are normally experienced separately are involuntarily and automatically joined together in experience (1, 2, 3). For example, some synesthetes experience a color when they hear a sound, although many instances of synesthesia also occur entirely within the visual sense. In this paper, I first mainly engage critically with Sollberger's view that there is reason to think that at least some synesthetic experiences can be viewed as truly veridical perceptions, and not as illusions or hallucinations (4). Among other things, I explore the possibility that many forms of synesthesia can be understood as experiencing what I will call "second-order secondary properties," that is, experiences of properties of objects induced by the secondary qualities of those objects. In doing so, I shed some light on why synesthesia is typically one-directional and its relation to some psychopathologies such as autism.
Topics: Autistic Disorder; Hallucinations; Humans; Synesthesia
PubMed: 33049694
DOI: 10.2741/4918 -
Nature Dec 2021There has been considerable recent progress in protein structure prediction using deep neural networks to predict inter-residue distances from amino acid sequences. Here...
There has been considerable recent progress in protein structure prediction using deep neural networks to predict inter-residue distances from amino acid sequences. Here we investigate whether the information captured by such networks is sufficiently rich to generate new folded proteins with sequences unrelated to those of the naturally occurring proteins used in training the models. We generate random amino acid sequences, and input them into the trRosetta structure prediction network to predict starting residue-residue distance maps, which, as expected, are quite featureless. We then carry out Monte Carlo sampling in amino acid sequence space, optimizing the contrast (Kullback-Leibler divergence) between the inter-residue distance distributions predicted by the network and background distributions averaged over all proteins. Optimization from different random starting points resulted in novel proteins spanning a wide range of sequences and predicted structures. We obtained synthetic genes encoding 129 of the network-'hallucinated' sequences, and expressed and purified the proteins in Escherichia coli; 27 of the proteins yielded monodisperse species with circular dichroism spectra consistent with the hallucinated structures. We determined the three-dimensional structures of three of the hallucinated proteins, two by X-ray crystallography and one by NMR, and these closely matched the hallucinated models. Thus, deep networks trained to predict native protein structures from their sequences can be inverted to design new proteins, and such networks and methods should contribute alongside traditional physics-based models to the de novo design of proteins with new functions.
Topics: Amino Acid Sequence; Crystallography, X-Ray; Hallucinations; Humans; Neural Networks, Computer; Protein Conformation; Proteins
PubMed: 34853475
DOI: 10.1038/s41586-021-04184-w -
Ugeskrift For Laeger Feb 2023Patients with late-onset schizophrenia form a subgroup of schizophrenia that to some extent differs from the typical Gestalt of schizophrenia. Therefore, some of these... (Review)
Review
Patients with late-onset schizophrenia form a subgroup of schizophrenia that to some extent differs from the typical Gestalt of schizophrenia. Therefore, some of these patients may be overlooked in the clinic. This review describes the characteristics of the late-onset subgroup: Overweight of women, higher education, has been or is still married, and with more children than patients with early onset schizophrenia. The symptomatology of the subgroup is characterised by persecutory delusions and auditory hallucination. Knowledge of this subgroup of patients may lead to attention in the clinic and hopefully have therapeutic value in the recovery process for the patients.
Topics: Child; Humans; Female; Schizophrenia; Delusions; Hallucinations; Schizophrenic Psychology; Ambulatory Care Facilities
PubMed: 36892229
DOI: No ID Found -
Psychopathology 2015Ketamine, the NMDA glutamate receptor antagonist drug, is increasingly employed as an experimental model of psychosis in healthy volunteers. At subanesthetic doses, it...
BACKGROUND
Ketamine, the NMDA glutamate receptor antagonist drug, is increasingly employed as an experimental model of psychosis in healthy volunteers. At subanesthetic doses, it safely and reversibly causes delusion-like ideas, amotivation and perceptual disruptions reminiscent of the aberrant salience experiences that characterize first-episode psychosis. However, auditory verbal hallucinations, a hallmark symptom of schizophrenia, have not been reported consistently in healthy volunteers even at high doses of ketamine.
SAMPLING AND METHODS
Here we present data from a set of healthy participants who received moderately dosed, placebo-controlled ketamine infusions in the reduced stimulation environment of the magnetic resonance imaging (MRI) scanner. We highlight the phenomenological experiences of 3 participants who experienced particularly vivid hallucinations.
RESULTS
Participants in this series reported auditory verbal and musical hallucinations at a ketamine dose that does not induce auditory hallucination outside of the scanner.
CONCLUSIONS
We interpret the observation of ketamine-induced auditory verbal hallucinations in the context of the reduced perceptual environment of the MRI scanner and offer an explanation grounded in predictive coding models of perception and psychosis - the brain fills in expected perceptual inputs, and it does so more in situations of altered perceptual input. The altered perceptual input of the MRI scanner creates a mismatch between top-down perceptual expectations and the heightened bottom-up signals induced by ketamine. Such circumstances induce aberrant percepts, including musical and auditory verbal hallucinations. We suggest that these circumstances might represent a useful experimental model of auditory verbal hallucinations and highlight the impact of ambient sensory stimuli on psychopathology.
Topics: Adult; Delusions; Dose-Response Relationship, Drug; Female; Frontal Lobe; Hallucinations; Humans; Ketamine; Magnetic Resonance Imaging; Male; Perception; Psychotic Disorders; Young Adult
PubMed: 26361209
DOI: 10.1159/000438675 -
Schizophrenia Bulletin Dec 2020
Topics: Adult; Antipsychotic Agents; Delusions; Hallucinations; Humans; Male; Olanzapine; Psychotic Disorders
PubMed: 31355406
DOI: 10.1093/schbul/sbz083 -
Journal of Mental Health (Abingdon,... Jun 2013For 25 years, the international Hearing Voices Movement and the U.K. Hearing Voices Network have campaigned to improve the lives of people who hear voices. In doing so,...
BACKGROUND
For 25 years, the international Hearing Voices Movement and the U.K. Hearing Voices Network have campaigned to improve the lives of people who hear voices. In doing so, they have introduced a new term into the mental health lexicon: "the voice-hearer."
AIMS
This article offers a "thick description" of the figure of "the voice-hearer."
METHOD
A selection of prominent texts (life narratives, research papers, videos and blogs), the majority produced by people active in the Hearing Voices or consumer/survivor/ex-patient movements, were analysed from an interdisciplinary medical humanities perspective.
RESULTS
"The voice-hearer" (i) asserts voice-hearing as a meaningful experience, (ii) challenges psychiatric authority and (iii) builds identity through sharing life narrative. While technically accurate, the definition of "the voice-hearer" as simply "a person who has experienced voice-hearing or auditory verbal hallucinations" fails to acknowledge that this is a complex, politically resonant and value-laden identity.
CONCLUSIONS
The figure of "the voice-hearer" comes into being through a specific set of narrative practices as an "expert by experience" who challenges the authority and diagnostic categories of mainstream psychiatry, especially the category of "schizophrenia."
Topics: Hallucinations; History, 20th Century; Humans; Mentally Ill Persons; Schizophrenia
PubMed: 23691942
DOI: 10.3109/09638237.2013.799267