Search

Aberrant neuronal coding of reward processing has been linked to psychosis. It remains unresolved how treatment with a partial dopamine agonist affects reward processing, and whether treatment affects reward processing differently in patients responding and not responding to treatment. Here, 33 antipsychotic-naïve psychosis patients and 33 matched healthy controls underwent functional magnetic resonance imaging before and after patients received aripiprazole monotherapy for six weeks. Processing of motivational salient events and negative outcome evaluation (NOE) was examined using a monetary incentive delay task. Psychopathology was assessed with the Positive and Negative Syndrome Scale, and responders were identified by having ≥30% reduction in positive symptoms (N=21). At baseline, patients displayed an increased NOE signal in the caudate and dorsolateral prefrontal cortex compared to healthy controls. In the caudate, the NOE signal was normalized at follow-up, and normalization was driven by responders. In responders only, there was a significant improvement in the motivational salience signal in the caudate at follow-up. Motivational salience and NOE signals in the caudate may be associated with a dopaminergic mechanism in patients characterized as responders which may not be the case in non-responders. Likewise, non-dopaminergic mechanism may underly abnormal NOE processing in dorsolateral prefrontal cortex.

Background Aberrant anticipation of motivational salient events and processing of outcome evaluation in striatal and prefrontal regions have been suggested to underlie psychosis. Altered glutamate levels have likewise been linked to schizophrenia. Glutamatergic abnormalities may affect the processing of motivational salience and outcome evaluation. It remains unresolved, whether glutamatergic dysfunction is associated with the coding of motivational salience and outcome evaluation in antipsychotic-naïve patients with first-episode psychosis. Methods Fifty-one antipsychotic-naïve patients with first-episode psychosis (22 ± 5.2 years, female/male: 31/20) and 52 healthy controls (HC) matched on age, sex, and parental education underwent functional magnetic resonance imaging and magnetic resonance spectroscopy (3T) in one session. Brain responses to motivational salience and negative outcome evaluation (NOE) were examined using a monetary incentive delay task. Glutamate levels were estimated in the left thalamus and anterior cingulate cortex using LCModel. Results Patients displayed a positive signal change to NOE in the caudate (p = 0.001) and dorsolateral prefrontal cortex (DLPFC; p = 0.003) compared to HC. No group difference was observed in motivational salience or in levels of glutamate. There was a different association between NOE signal in the caudate and DLPFC and thalamic glutamate levels in patients and HC due to a negative correlation in patients (caudate: p = 0.004, DLPFC: p = 0.005) that was not seen in HC. Conclusions Our findings confirm prior findings of abnormal outcome evaluation as a part of the pathophysiology of schizophrenia. The results also suggest a possible link between thalamic glutamate and NOE signaling in patients with first-episode psychosis.

В настоящем обзоре представлен анализ данных литературы, посвященных исследованиям нейросети салиенса, динамике формирования нейросети в процессе онтогенеза головного мозга, дисрегуляции салиенса при нейродегенеративных и нейропсихических расстройствах. Рассмотрена роль дофаминергического дисбаланса в формировании аберрантного салиенса при шизофрении. Отдельное внимание уделено исследованиям значения мотивационного салиенса, и системы вознаграждения в патогенезе аддиктивных расстройств., This review presents an analysis of the literature on studies of the salience neural network, the dynamics of neural network formation during ontogenesis of the brain, and salience dysregulation in neurodegenerative and neuropsychiatric disorders. The role of dopaminergic imbalance in the formation of aberrant salience in schizophrenia is considered. Particular attention is paid to the studies of the significance of motivational salience and reward system in the pathogenesis of addictive disorders.

В настоящем обзоре представлен анализ данных литературы, посвященных исследованиям нейросети салиенса, динамике формирования нейросети в процессе онтогенеза головного мозга, дисрегуляции салиенса при нейродегенеративных и нейропсихических расстройствах. Рассмотрена роль дофаминергического дисбаланса в формировании аберрантного салиенса при шизофрении. Отдельное внимание уделено исследованиям значения мотивационного салиенса, и системы вознаграждения в патогенезе аддиктивных расстройств., This review presents an analysis of the literature on studies of the salience neural network, the dynamics of neural network formation during ontogenesis of the brain, and salience dysregulation in neurodegenerative and neuropsychiatric disorders. The role of dopaminergic imbalance in the formation of aberrant salience in schizophrenia is considered. Particular attention is paid to the studies of the significance of motivational salience and reward system in the pathogenesis of addictive disorders.

This article gives a brief overview of a study conducted on motivation for learning as an important element of social and economic sciences in the context of the sphere of security and defense. The research is an important scientific work of the author and was developed in the period 2012-2018. At present, its results have been approved, considered appropriate and acceptable, and are applied at the National Military University in Bulgaria.

This article gives a brief overview of a study conducted on motivation for learning as an important element of social and economic sciences in the context of the sphere of security and defense. The research is an important scientific work of the author and was developed in the period 2012-2018. At present, its results have been approved, considered appropriate and acceptable, and are applied at the National Military University in Bulgaria.