Selima Jelili, Zeineb Abbes, Souhail Bannour, Melek Hajri, Houda Ben Yahia, Maissa Touati, Josef Ventura, Sami Ouanes, Ali Mrabet, Asma Bouden
Abstract: Background: Impaired cognition is at the core of schizophrenia and those cognitive deficits could precede the onset of the clinical symptoms of psychosis. Several studies have suggested that individuals at Ultra-High Risk (UHR) of psychosis show similar cognitive impairments. However, previous findings in this field are heterogeneous regarding which cognitive changes are specific to the development of schizophrenia. Our aim was to investigate the neurocognitive performance of adolescents at UHR of psychosis as compared to Help-Seeking Controls. Methods: We studied 33 adolescents consisting of 17 at UHR of psychosis and 16 help-seeking adolescents, meeting the inclusion criteria of a National Research protocol for Early Detection of Psychosis. Six neurocognitive domains were measured with validated instruments: executive functions, processing speed, cognitive flexibility, attention, visual memory, and verbal fluency. Analyses compared cognitive performance between the two groups. Results: The UHR subjects had significantly lower performance than the control group in visual memory (p=0.010) and verbal fluency (p=0.040; p= 0.032; p=0.029). Conclusions: Our findings suggest that visual memory and verbal fluency could serve as specific markers in UHR adolescents. However, experimental tasks challenging these cognitive functions are needed to interpret the predictive value of these findings.
Keywords: early detection, neurocognition, psychosis, schizophrenia