Evidence map›Paper›PMID 42351388›Full record

ArticleJournal of Parkinson's disease2026

Deficits in episodic memory and executive functions in relation to CB1 receptor availability in Parkinson's disease.

Riikka M Ajalin, Haidar Al-Abdulrasul, Jouni M Tuisku, Mira Karrasch, Jussi Hirvonen, Anna K Kirjavainen, Henrik Zetterberg, Juha O Rinne, Anna E Brück

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Article in Journal of Parkinson's disease, 2026. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Not yet cited in PubMed.

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1 · What the graph read from it

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2 · The registry

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3 · Its place in the literature

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4 · The record

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5 · Who and what money

Authors and funding

9 authors.

Riikka M AjalinTurku PET Centre, University of Turku and Turku University Hospital, Turku, Finland.ORCID 0000-0001-9116-7516
Haidar Al-AbdulrasulTurku PET Centre, University of Turku and Turku University Hospital, Turku, Finland.
Jouni M TuiskuTurku PET Centre, University of Turku and Turku University Hospital, Turku, Finland.
Mira KarraschDepartment of Psychology, Åbo Akademi University, Turku, Finland.
Jussi HirvonenTurku PET Centre, University of Turku and Turku University Hospital, Turku, Finland.
Anna K KirjavainenTurku PET Centre, University of Turku and Turku University Hospital, Turku, Finland.
Henrik ZetterbergDepartment of Psychiatry and Neurochemistry, Institute of Neuroscience and Physiology, The Sahlgrenska Academy at the University of Gothenburg, Mölndal, Sweden.
Juha O RinneTurku PET Centre, University of Turku and Turku University Hospital, Turku, Finland.
Anna E BrückTurku PET Centre, University of Turku and Turku University Hospital, Turku, Finland.

Funding

No grant is acknowledged in the PubMed record.

6 · The paper itself

Abstract

BackgroundThe endocannabinoid system (ECS) is important for several neurophysiological functions, including the regulation of emotions and cognitive processes. The most abundant brain cannabinoid receptor is cannabinoid receptor type 1 (CB1R). Several preclinical studies in Parkinson's disease (PD) models suggest that modulating CB1R may impact cognitive processing. However, there are very limited studies of the relation between CB1R and cognitive processing in PD patients.ObjectiveTo explore the relationship between CB1R availability and cognitive dysfunction in PD with [18F]FMPEP-d2 positron emission tomography (PET).MethodsA total of 23 individuals with PD underwent [18F]FMPEP-d2 PET to measure cerebral CB1R availability. Cognitive symptoms were evaluated using a standardized neuropsychological test battery covering various cognitive domains, such as episodic and working memory, executive functioning, language function, visuospatial function and attention, and were correlated with CB1R availability using voxel-wise regression analysis corrected for multiple comparisons using false discovery rate (FDR) at p < 0.01.ResultsPD patients with poorer performance in episodic memory tests showed lower CB1R availability, particularly in the cingulate, temporal, and visual cortices, and thalami. Also, PD patients with poorer executive functioning showed lower CB1R availability predominantly in the insulae, caudate nuclei, thalami, brainstem, and temporal cortices. No relationship was found between CB1R availability and language function, visuospatial function, or working memory capacity.ConclusionsDecreased CB1R availability in PD patients is correlated with episodic memory impairment and executive dysfunction, suggesting that the ECS has a role in the pathophysiology of cognitive symptoms in PD.Plain language summary titleProblems with Episodic Memory or Executive Functions are Related to Disturbances in Endocannabinoid System Functioning in Parkinson's Disease.

Indexed as

Cognitive DysfunctionExecutive FunctionMemory DisordersMemory, EpisodicParkinson DiseaseReceptor, Cannabinoid, CB1AgedFemaleHumansMaleMiddle AgedNeuropsychological TestsPositron-Emission TomographyReceptor, Cannabinoid, CB1CB1Rcognitionendocannabinoid systemimagingnon-motor symptomsparkinson's diseasepathophysiology

Identifiers

PMID42351388
PMCPMC13435193

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Read under generation 80e0d062 · epoch 390. Bibliography from PubMed, PubMed Central and OpenAlex; grants from NIH RePORTER; trial links from ClinicalTrials.gov; estimates, votes and beliefs from the OpenQuestion graph.