Neurocognitive deficits and trajectories in individuals at clinical high risk for psychosis

Objective. This review aims to examine neurocognitive deficits in individuals at clinical high risk (CHR) for psychosis, focusing on comparisons with healthy controls (HCs), differences between CHR individuals who transition to psychosis (CHR-T) and those who do not (CHR-NT), the relationship between cognition, symptoms, and functioning, and longitudinal trajectories of cognitive performance.

Methods. A systematic search of PubMed identified studies published between January 1998 and November 2024. Inclusion criteria required studies to assess neurocognitive performance in CHR individuals using validated criteria, compare CHR individuals to HCs or CHR subgroups (CHR-T/CHR-NT), and evaluate cognitive domains. The findings were analyzed to highlight the most affected cognitive domains and to explore longitudinal patterns of change.

Results. CHR individuals exhibited widespread neurocognitive impairments, with verbal memory, processing speed, and executive functions most consistently affected compared to HCs. CHR-T individuals demonstrated greater baseline deficits and progressive reductions in cognitive performance over time, particularly in verbal memory and processing speed, while CHR-NT showed stability or improvement. Neurocognitive deficits were linked to symptom severity and poorer functional outcomes, with CHR-NT improvements associated with reduced symptoms. Longitudinal analyses highlighted heterogeneous trajectories, underscoring the importance of identifying early cognitive markers of transition risk.

Conclusions. Neurocognitive deficits are central to psychosis risk, with distinct trajectories differentiating CHR-T from CHR-NT individuals. These findings emphasize the need for targeted interventions and integration of neurocognitive assessments in clinical practice to enhance prediction and prevention efforts.