Psychosis-like experiences and cognition in young adults: an observational and Mendelian randomisation study

Background: Psychosis-like experiences (PLEs) are common and associated with mental health problems and poorer cognitive function. There is limited longitudinal research examining associations between cognition and PLEs in early adulthood. Aims: We investigated the association of PLEs with different domains of cognitive function, using cross-sectional and longitudinal observational, and Mendelian randomisation (MR) analyses. Method: Participants from the Avon Longitudinal Study of Parents and Children (ALSPAC) completed tasks of working memory at age 18 and 24, and tasks of response inhibition and facial emotion recognition at age 24. Semi-structured interviews at age 18 and 24 established presence of PLEs (none vs. suspected/definite). Cross-sectional and prospective regression analysis tested associations between PLEs and cognition (N=3,087 imputed sample). MR examined causal pathways between schizophrenia liability and cognition. Results: The fully adjusted models indicated that PLEs were associated with poorer working memory performance (cross-sectional analyses: b=-0.18, 95% CI -0.27 to -0.08, p<0.001; prospective analyses: b=-0.18, 95% CI -0.31 to -0.06, p<0.01). A similar pattern of results was found for PLEs and response inhibition (cross-sectional analyses: b=7.29, 95% CI 0.96 to 13.62, p=0.02; prospective analyses: b=10.29, 95% CI 1.78 to 18.97, p=0.02). We did not find evidence to suggest an association between PLEs and facial emotion recognition. MR analyses were underpowered and did not support observational results. Conclusions: In young adults, PLEs are associated with poorer concurrent and future working memory and response inhibition. Better powered genetically informed studies are needed to determine if these associations are causal.