IntroductionLimited clinical relevance of attenuated psychotic symptoms before the turn from early to late adolescence, i.e., age 15/16, was reported.ObjectiveThis emphasizes the potentially important role of neurodevelopmental aspects in the early detection of psychoses.AimsWe examined the age effect on prevalence and clinical relevance of 14 cognitive and perceptive basic symptoms (BS) included in risk criteria of psychosis in a random representative 8–40-year-old community sample (n = 689).MethodsParticipants underwent clinical interviews for BS, psychosocial functioning and current mental disorder on the telephone.ResultsBS were reported by 18% of participants, mainly cognitive BS (15%). Age seemed to affect perceptive and cognitive BS differently, indicating an age threshold for perceptive BS in late adolescence (around age 18) and for cognitive BS in young adulthood (early twenties) – with higher prevalence, but a lesser association with functional deficits and the presence of mental disorder in the below-threshold groups. Thereby, effects of the interaction between age and BS on functioning and mental disorder were commonly stronger than individual effects of age and BS.ConclusionDifferential age effects of perceptual and cognitive BS seem to follow normal brain maturation processes, in which they might occur as infrequent and temporary nonpathological disturbances. Their persistence or occurrence after the conclusion of main brain maturation processes, however, might signify aberrant maturation processes. Thus, BS might provide important insight into the pathogenesis of psychosis and into potential neuroprotective targets.Disclosure of interestThe authors have not supplied their declaration of competing interest.