Diagnostic and Differential Challenges of Psychoses in Adolescence: A Cognitive Perspective

Introduction: Adolescence is a period of high neuropsychological plasticity and vulnerability for the onset of psychotic symptoms. Diagnostic criteria validated in adults do not always capture the complex developmental dynamic and the overlap with anxiety, mood, and trauma, which can lead to diagnostic errors and inadequate interventions. Aim: The study aims to investigate how to diagnose and differentiate the challenges of psychoses in adolescence. Methodology: An integrative narrative review on PubMed/MEDLINE and SciELO of studies published between 2020 and June 2025, focusing on childhood/adolescent psychosis, clinical high risk (CHR), phenomenological semiology, and differential diagnoses (substances, autoimmune/neurological conditions, dissociative states). Systematic reviews, meta-analyses, cohort studies, and clinical guidelines were included, prioritising Brazilian evidence when available. Results: Recent evidence points to heterogeneity and dimensional continuity of psychotic experiences, CHR conversion rates of 20–30% in 2–3 years, a high prevalence of negative symptoms and cognitive deficits with functional impact, a marked influence of sociocultural determinants and traumas, and the relevance of screening for mimics such as high-potency cannabis use and anti-NMDAR encephalitis. Useful clinical subtypes for adolescence are described: anxiolytic-apoplectic, subacute, dysmorphophobic, and functional/bipolar psychoses. The evaluation must be multidimensional, including neurocognitive examinations, substance use screening, investigation of medical comorbidities, and the use of specific scales, such as the Scale of Prodromal Symptoms (SOPS) and the Comprehensive Assessment of At-Risk Mental States (CAARMS), which are widely used in early intervention centres. Discussion: Diagnostic approaches centred on development and the self, with a phenomenological listening and longitudinal follow-up, can increase diagnostic accuracy and avoid early stigmatisation. Implications for public policies, multi-professional management, and future research are discussed. Conclusion: The integration of detailed phenomenological assessment, longitudinal monitoring, and targeted screening for mimicking and risk factors allows for increased diagnostic precision in adolescents, the anticipation of therapeutic interventions, and the reduction of functional damage. This approach contributes to more individualised clinical decisions, a decrease in early stigmatisation, and the optimisation of public policies and early intervention programs, promoting more effective, humanised, and culturally sensitive mental healthcare for adolescents.