Neurocognitive deficits in participants at clinical high-risk for psychosis: relationships to clinical symptoms and functioning

Background: Neurocognitive impairments are a core feature of schizophrenia (ScZ) contributing to ongoing psychopathology and poor psychosocial functioning. These deficits have been consistently observed before illness onset in individuals at clinical high risk for psychosis (CHR) suggesting that they may be an endophenotype of the disorder. Traditional CHR studies have recruited exclusively using clinical pathways however, it has been recently reported that the majority of individuals who present with a first episode of psychosis have not been seen by specialised prodromal services suggesting that these studies only capture a subgroup of CHR individuals (Ajnakina et al., 2017). Few studies have included CHR individuals recruited from community pathways who may differ from those recruited clinically in the degree of neurocognitive impairment and clinical trajectory. Neurocognitive functioning in CHR individuals may also be influenced by the high prevalence of comorbid non-psychotic disorders experienced by the population. So far, few studies have addressed this question which may provide valuable information to improve functional and clinical outcome in those at-risk. Aim 1: To explore the degree of neurocognitive impairment in CHR-participants recruited from the general population and identify their relationship with positive symptom severity and functioning. Aim 2: To investigate the influence of comorbid non-psychotic disorders on neurocognitive functioning in CHR-participants by identifying the degree of neurocognitive impairment in a CHR-negative group who scored below the CHR threshold but are characterised by non-psychotic disorders Aim 3: To explore the association between baseline neurocognitive functioning and clinical outcome at 12 months. Methods: The Youth Mental Health and Resilience Study (You-R) recruited CHR- and CHR-negative participants from the general population using a unique web-based screening tool. At baseline neuropsychological tests togethe