Neuroscience
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Olfactory dysfunction is an early sign of such neurodegenerative diseases as Parkinson's (PD) and Alzheimer's (AD), and is often present in Mild Cognitive Impairment (MCI), a precursor of AD. Understanding neuro-temporal relationships, i.e., functional connectivity, between olfactory eloquent structures in such disorders, could shed light on their basic pathophysiology. To this end, we employed region-based analyses using resting-state functional magnetic resonance imaging (rs-fMRI) obtained from cognitively normal (CN), MCI, and PD patients with cognitive impairment (PD-CogImp). ⋯ Regardless of study group, males showed significantly higher connectivity than females in connections involving the orbitofrontal cortex. The logistic regression model trained using the top discriminatory features revealed that caudate was the most involved olfaction-related brain structure (accuracy = 0.88, Area under the Receiver operator characteristic curve of 0.90). In aggregate, our study demonstrates that resting functional connectivity among olfactory eloquent structures has potential value in better understanding the pathophysiology of several neurodegenerative diseases.
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Alzheimer's disease (AD) is the most common form of neurodegeneration which currently has no effective treatment. Ferroptosis is a new style of programmed cell death and is widely implicated in the pathogenesis and progression of AD. Decursin has been shown widely neuroprotective effects but poorly understood about the underlying mechanisms between decursin and ferroptosis in AD. ⋯ Taken together, our data for the first time suggest that decursin could ameliorate neurotoxicity induced by glutamate by attenuating ferroptosis via alleviating cellular iron levels by up-regulating FTH1 expression which is attributing to its promotion of Nrf2 translocation into the nucleus in SH-SY5Y neuroblastoma cells. Hence, decursin might be a novel and promising therapeutic option for AD. In addition, our study also provided some new clues to potential target for the intervention and therapy of AD.
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Constipation frequently occurs in patients with Parkinson's disease (PD) and may be related to cognitive and emotional disorders. The aim of this study is to investigate the clinical and brain functional characteristics of patients with PD presenting with constipation. ⋯ Constipation in patients with PD is closely related to emotional and cognitive impairments, abnormal activity and FC of brain regions such as the right insula and bilateral OFC may play an important role in this.
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Anhedonia is one of the core features of the negative symptoms of schizophrenia and can be extremely burdensome. Our study applied resting-state functional magnetic resonance imaging (fMRI)-based support vector regression (SVR) to predict anhedonia in patients with first-episode schizophrenia (FES) and analysed the correlation between the wavelet-based amplitude low-frequency fluctuation (wavelet-ALFF) of the main brain region and anhedonia. We recruited 31 patients with FES and 33 healthy controls (HCs) from the Affiliated Brain Hospital of Guangzhou Medical University. ⋯ The SVR analysis showed that wavelet-ALFF, based primarily on the right putamen (r = 0.40, P<0.05) and right superior occipital gyrus (r = -0.39, P<0.05), was effective in predicting consummatory pleasure scores with an accuracy of 56.43 %. Our study shows that abnormal spontaneous neural activity in FES may be related to the state of consummatory anhedonia in FES. Wavelet-ALFF changes in the right putamen and superior occipital gyrus may be a biological feature of FES with anhedonia and could serve as a potential biological marker of FES with anhedonia.
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In daily life, individuals pay attention to emotional facial expressions and dynamically choose how to shift their attention, i.e. either overtly (with eye-movements) or covertly (without eye-movements). However, research on attention to emotional faces has mostly been conducted in controlled laboratory settings, in which people were instructed where to look. The current preregistered study co-registered EEG and eye-tracking to investigate differences in emotion-driven attention between instructed and uninstructed natural attention shifts in 48 adults. ⋯ In three counterbalanced blocks participants were instructed to either move their eyes overtly to the peripheral face, keep fixating the center and therefore covertly shift their attention, or freely look wherever they would like to look. We found that emotional content had stronger effects on the amplitude of the Early Posterior Negativity when participants shifted attention naturally, and that natural shifts of attention differed from instructed shifts in both saccade behavior and neural mechanisms. In summary, our results emphasize the importance of investigating modulation of attention using paradigms that allow participants to allocate their attention naturally.