Schizophrenia Bulletin
August 5, 2020
Pantelis Leptourgos, Martin Fortier-Davy, Robin Carhart‐Harris et al.
88 citations
A multidisciplinary working group reviewed evidence on the similarities and differences between hallucinations induced by psychedelics and those occurring in schizophrenia-spectrum disorders, examining data from pharmacology, brain imaging, phenomenology, and anthropology. The authors highlight both shared features and distinct characteristics across these scales, and attempt to integrate findings using computational approaches. They conclude with recommendations for future research, emphasizing the need for further study to clarify the relationship between these types of hallucinations.
Schizophrenia Bulletin
December 18, 2015
Filip Španiel, Jaroslav Tintěra, Jan Rydlo et al.
55 citations
Disturbance of the sense of self may be a core marker of schizophrenia. In patients with first-episode schizophrenia-spectrum disorders compared with healthy controls, self-agency experience was associated with reduced cortical activation in the medial frontal gyrus and posterior cingulate gyrus. The ability to judge whether an action is one's own or another's depends on anti-correlated switching between the default mode and central-executive networks, a mechanism substantially impaired in the patient group during the task.
Journal of Psychopharmacology
June 3, 2019
Yuliya Zaytseva, Jiřı́ Horáček, Jaroslav Hlinka et al.
25 citations
Delta-9-tetrahydrocannabinol, the active compound in cannabis, temporarily alters how brain regions communicate with each other. In 19 occasional cannabis users who underwent two resting-state fMRI scans—one shortly after smoking a cannabis cigarette and one after at least a week without cannabis—a transient connectivity state appeared only during intoxication. This state showed high connectivity within and between auditory and somato-motor cortices, along with anti-correlation with subcortical structures and the cerebellum. Subjective perceptual changes and THC plasma levels were linked to this state, suggesting a neural biomarker of cannabis intoxication.
The Oxford Handbook of Phenomenological Psychopathology
July 4, 2019
Aaron Mishara, Yuliya Zaytseva
4 citations
Hallucinations in schizophrenia may be understood as part of self-disturbances, arising from non-conscious low-level sensory anomalies and a disrupted perception-action cycle, rather than solely from problems of phenomenal consciousness. Historical phenomenological analyses by the Early Heidelberg School (1909–1932), particularly Mayer-Gross, who studied hypnagogic experiences, mescaline-induced model psychoses, and detailed accounts from people with schizophrenia, shaped this view. Debates with contemporaries led to the conclusion that hallucinations in schizophrenia relate to shifts in the organization of consciousness, later influencing Schneider's First Rank Symptoms. The chapter assesses how these early contributions inform current phenomenological understanding of hallucinations.