Schizophr Bull
January 26, 2012
Oliver Howes, Paul Shotbolt, Michael Bloomfield et al.
94 citations
Auditory hallucinations in healthy individuals are associated with altered dopamine function in the brain. Using [18F]-DOPA PET imaging, the study found that healthy people who experience auditory hallucinations show differences in dopaminergic activity compared to those who do not, suggesting that dopamine dysfunction may be a trait marker along the psychosis spectrum. The findings indicate that even in the absence of a clinical diagnosis, hallucination proneness is linked to measurable neurochemical variations.
Schizophrenia
April 23, 2022
Mascha M.J. Linszen, Janna De Boer, Maya Schutte et al.
55 citations
Hallucinations occur in 6-15% of the general population, but their detailed characteristics are poorly understood. In a large online survey of 10,448 participants aged 14-88, auditory hallucinations were most common in the past month (29.5%), followed by visual (21.5%), tactile (19.9%), and olfactory (17.3%); nearly half (47.6%) experienced hallucinations in two or more senses. Many participants rated their hallucinations as severe due to negative content (16.0-31.6%), distress (10.5-16.8%), or dysfunction (12.7-17.3%). Decreased insight occurred in 10.2-11.4%, hypnagogia in 9.0-10.6%, and bereavement hallucinations in 2.8%. Delusions were rare (7.0%) but significantly associated with recent hallucinations. The findings indicate a wide variety of hallucination phenomenology in the general population and support a phenomenological continuum.
Neuroscience and Biobehavioral Reviews
September 1, 2024
Jesca E De Jager, Rutger Boesjes, Gijs H J Roelandt et al.
13 citations
Electroconvulsive shocks (ECS) and ketamine are fast-acting antidepressant treatments whose shared neurobiological mechanisms are explored in this systematic review of animal models of depression. Both interventions consistently increase hippocampal neurogenesis and brain-derived neurotrophic factor (BDNF) levels. They also positively affect glutamatergic neurotransmission, astrocyte and neuronal morphology, synaptic density, vasculature, and functional plasticity. Restoration of neuroplasticity may be a common mechanism underlying their antidepressant efficacy. Fewer studies have examined these processes after ECS. Understanding these shared fundamental mechanisms could help develop novel therapeutic approaches for severe depression.
Schizophrenia Bulletin
February 24, 2023
Salma M Khaled, Sanne G Brederoo, Arij Yehya et al.
8 citations
Hallucinations in nonclinical populations are shaped by culture. Comparing Dutch and Qatari adults (2,999 each) on the Questionnaire for Psychotic Experiences, tactile and olfactory hallucinations occurred at similar lifetime rates in both countries. Auditory and visual hallucinations were twice as common in the Dutch sample, and Dutch participants reported younger ages of onset for auditory and tactile hallucinations. Although Qatari participants reported fewer auditory and visual hallucinations overall, those who experienced them had higher mean scores for past-week hallucinations, more impact on daily functioning, and more frequent commanding voices. The findings suggest hallucinations in the Qatari sample carried greater clinical relevance, with implications for early screening and prevention.
Frontiers in Psychiatry
January 1, 2022
Arij Yehya, Salma M Khaled, Iris E C Sommer et al.
4 citations
Psychotic-like experiences (hallucinations or delusions below the threshold of a disorder) are common in the general population. In interviews with 12 female undergraduate students in Qatar, these experiences were prevalent. Students' descriptions showed that culture and religion shaped the types of hallucinations and some delusions they reported. Many students normalized their experiences and linked them to real-life events, possibly as a defense against the stigma of mental illness and being labeled abnormal.
JMIR Ment Health
June 16, 2026
Lorenzo Ghelfi, Jack Healy, Francesco Piacenza et al.
A scoping review of 10 studies found that artificial intelligence methods, including machine learning and digital phenotyping via smartphones and wearables, show promise for detecting relapse in psychotic disorders but have significant limitations. The sensitivity of AI models ranged from 0.25 to 0.77 and specificity from 0.06 to 0.88, with area under the curve between 0.63 and 0.78. Models were heterogeneous and most findings were not replicated. The review concludes that while personalized approaches with individual-level modeling are promising, larger studies and methods such as large language models are needed before AI can be used in real-world clinical practice.
Schizophrenia Bulletin
March 22, 2023
Eric J Tan, Iris E C Sommer, Lena Palaniyappan
This special issue examines the role of language in psychosis, exploring the connections between formal thought disorder and conceptual disorganization, along with speech and language markers and their neural underpinnings. It also discusses the use of computational methods to analyze language in psychosis and the potential of speech and language data for digital phenotyping in psychiatry.