No association between cortical dopamine D2 receptor availability and cognition in antipsychotic-naive first-episode psychosis

• Main Authors: Maria Lee, Helena Fatouros-Bergman, Pontus Plavén-Sigray, Pauliina Ikonen Victorsson, Carl M. Sellgren, Sophie Erhardt, Lena Flyckt, Lars Farde, Simon Cervenka
• Format: Article
• Language: English
• Published: Nature Publishing Group 2021-09-01
• Series: npj Schizophrenia
• Online Access: https://doi.org/10.1038/s41537-021-00176-x

Abstract Cognitive impairment is an important predictor of disability in schizophrenia. Dopamine neurotransmission in cortical brain regions has been suggested to be of importance for higher-order cognitive processes. The aim of this study was to examine the relationship between extrastriatal dopamine D2-R availability and cognitive function, using positron emission tomography and the high-affinity D2-R radioligand [11C]FLB 457, in an antipsychotic-naive sample of 18 first-episode psychosis patients and 16 control subjects. We observed no significant associations between D2-R binding in the dorsolateral prefrontal cortex or hippocampus (β = 0.013–0.074, partial r = −0.037–0.273, p = 0.131–0.841). Instead, using Bayesian statistics, we found moderate support for the null hypothesis of no relationship (BFH0:H1 = 3.3–8.2). Theoretically, our findings may suggest a lack of detrimental effects of D2-R antagonist drugs on cognition in schizophrenia patients, in line with clinical observations.