New approaches to understanding hallucinations in Parkinson's disease: phenomenology and possible origins.
Marco Onofrj, Astrid Thomas, Laura Bonanni
Expert Review of Neurotherapeutics December 2007 DOI: 10.1586/14737175.7.12.1731 (opens in new tab)
Study at a glance
AI-extracted from the abstract| Characteristics | Review Peer reviewed |
|---|---|
| Topics | Philosophy of mind |
| Key findings | The authors argue that hallucinations are a hallmark of Parkinson's disease and dementia with Lewy bodies and predict Lewy body deposition, that existing mechanistic models (visual dysfunction, dream overflow, cognitive impairment) each face objections, and that only clozapine has positive evidence-based efficacy ratings, while other drug classes may affect hallucination types differently. |
Abstract
The authors review current literature on hallucinations in Parkinson's disease (PD). Recent neuropathological studies showed that hallucinations occur in synucleinopathies and are a significant predictor of Lewy Body depositions. Therefore, hallucinations are a hallmark of PD and of dementia with Lewy Bodies. Visual hallucinations are mostly complex and kinematic; preserved or disturbed insight on the nature of hallucinations is a major prognostic factor, although eventually all hallucinators will present with reduced insight. Current theories on the origin of hallucinations point to visual dysfunction, dream overflow and cognitive impairment, yet objection can be raised on each one of the putative models of hallucinations. Understanding of the origin of hallucinations is required in order to develop treatments: all treatment evaluations were focused in general on psychosis, and only clozapine obtained positive evidence-based ratings on efficacy. However, it is likely that cholinesterase inhibitors, antipsychotics and anti-5-hydroxytryptamine(3) agents and drugs acting on sleep regulation will have different and perhaps opposite effects on different types of hallucinations, whether they are accompanied by disturbed insight, sleep disorders or other psychotic features. Further studies will try to separate phenomenology and responses to treatment and will investigate the relevance of concomitant sleep disorders and abnormality of frontoparietal networks involved in the attention process.
Comparable studies
Other narrative reviews on philosophy of mind, most cited first.
| Study | Year | Design | Participants |
|---|---|---|---|
| Body Consciousness: A Philosophy of Mindfulness and Somaesthetics | 2008 | Review article | |
| Phenomenology, Structure, and Dynamic of Psychedelic States | 2016 | Review | |
| Classic Hallucinogens and Mystical Experiences: Phenomenology and Neural Correlates. | 2018 | Review | |
| The lived experience of psychosis: a bottom-up review co-written by experts by experience and academics. Individuals with lived experience of psychosis, family members, and carers | 2022 | Co-written bottom-up review | |
| From autopoiesis to neurophenomenology: Francisco Varela's exploration of the biophysics of being. | 2003 | Review |
Citations in the library
Cites 5
- Repeated visual hallucinations in Parkinson's disease as disturbed external/internal perceptions: focused review and a new integrative model. Movement Disorders February 2005
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- Acetylcholine and hallucinations: disease-related compared to drug-induced alterations in human consciousness. Brain and Cognition August 1, 1995
- Chronic behavioral disorders of human REM sleep: a new category of parasomnia. Sleep June 1, 1986