Abstract
Increasing evidence indicates that psychosis spectrum disorders are neurodevelopmental disorders linked to early life. Motor impairments are proposed as a key early marker of risk for psychosis spectrum disorders. Here, we explored the association between childhood impaired motor development and psychotic experiences (PE) in adolescents. Participants were 658 adolescents from a cohort oversampled on their self-reported emotional and behavioral problems. Parents reported retrospectively on childhood motor development, including onset of walking, aptitude in ballgames, balance, and smoothness of movement. Adolescents completed the Prodromal Questionnaire (PQ-16) to assess PE at two time points (mean age 14.73 at first measurement and 17.78 at follow-up). Multiple linear regression analyses were performed to assess associations between childhood impaired motor development and adolescent PE. Childhood impaired motor development was associated with higher levels of adolescent PE (β = 0.23, 95% CI 0.08; 0.38) at age 17, but not at age 15. In addition, motor impairments were associated with an increase in PE between the two time points. This association was especially apparent in hallucinatory experiences (β = 0.26, 95% CI 0.13; 0.39), but not in delusional experiences. Childhood impaired motor development may signal an increased risk for adolescent PE, emphasizing the need for precise assessment tools and further research into these associations. This study supports the notion of psychosis spectrum disorders as neurodevelopmental in nature and highlights the role of early risk markers in identifying these disorders.