Ivan Koychev

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A number of compounds aimed at improving cognition in schizophrenia have failed to demonstrate efficacy in Phase 2 clinical trials. Translational studies using biomarkers in surrogate populations, such as schizotypy, could be used to assess the efficacy of novel compounds. In this study, we aimed to validate the sensitivity and inter-site reliability of(More)
We aimed to clarify the importance of early visual processing deficits for the formation of cognitive deficits in the schizophrenia spectrum. We carried out an event-related potential (ERP) study using a computerised delayed matching to sample working memory (WM) task on a sample of volunteers with high and low scores on the Schizotypal Personality(More)
INTRODUCTION: Schizophrenia is currently diagnosed on the basis of patient reports and clinical observations. A diagnosis based on aetiology is inherently more reliable due to being closer to the disease process than the overt clinical manifestations. Accordingly, recent research in schizophrenia has focused on the development of biomarkers in a bit to(More)
The increasing demand to develop more efficient compounds to treat cognitive impairments in schizophrenia has led to the development of experimental model systems. One such model system combines the study of surrogate populations expressing high levels of schizotypy with oculomotor biomarkers. We aimed (1) to replicate oculomotor deficits in a psychometric(More)
BACKGROUND Combining PET amyloid-β (Aβ) and tau imaging may be critical for tracking disease progression in Alzheimer's disease (AD). OBJECTIVE We sought to characterize the relationship between Aβ and tau ligands as well as with other measures of pathology. METHODS We conducted a multi-center observational study in early AD (MMSE >20) participants aged(More)
BACKGROUND Sodium nitroprusside (SNP) has been reported to rapidly reduce psychotic symptoms in patients with schizophrenia. This has the potential to revolutionize treatment for schizophrenia. In this study, we tested the hypothesis that SNP leads to a reduction in psychotic symptoms and an improvement in spatial working memory (SWM) performance in(More)
The development of drugs to improve cognition in patients with schizophrenia is a major unmet clinical need. A number of promising compounds failed in recent clinical trials, a pattern linked to poor translation between preclinical and clinical stages of drug development. Seeking proof of efficacy in early Phase 1 studies in surrogate patient populations(More)
Antipsychotic drugs are the mainstay of treatment for schizophrenia but they have little effect on core negative symptoms or cognitive impairment. To meet the deficiencies of current treatments, novel potential compounds are emerging from preclinical research but translation to clinical success has been poor. This article evaluates the possibility that(More)
Neural oscillatory deficits have been proposed to be a core feature of schizophrenia spectrum disorders. In this study we aimed to confirm this by examining early evoked oscillatory patterns in the EEG theta, beta and gamma bands in individuals with high schizotypal personality trait scores. We carried out an event-related experiment using a computerised(More)