Neuroscience
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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.
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Respiratory muscle paralysis due to trauma or neurodegenerative diseases can have devastating consequences. Only a few studies have investigated the reconstruction of motor function in denervated diaphragms caused by such conditions. Here, we studied the efficacy of transplanting E14 embryonic spinal motor neurons (SMNs) into peripheral nerve grafts for functionally reconstructing a denervated diaphragm in a rat model. ⋯ The SMNs transplanted into the peripheral nerve grafts formed a structure similar to the spinal cord, and the neuromuscular junction of the denervated diaphragm was reinnervated. These findings suggest the establishment of an ectopic motor neuron pool in the peripheral nerve graft. Free peripheral intra-nerve SMN transplantation in combination with NMES, which can be applied for diaphragmatic pacing, offers novel insights into the development of neuroregenerative therapies for treating life-threatening and intractable respiratory muscle paralysis caused by severe nerve damage and degenerative diseases.
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Parkinson's disease (PD) is the second-most prevalent neurodegenerative disease worldwide, which worsens with advancing age. It is a common movement disorder and is often associated with several vascular diseases with decreased stroke frequency. Circulating platelets substantially regulate vascular complications, including stroke, and share striking similarities with PD neurons. ⋯ Phase-contrast and confocal microscopic studies further verified the results from the above experiments. Our findings showed that 6-OHDA treatment significantly inhibited thrombin (a platelet agonist)-induced functions, including adhesion, activation, aggregation, secretion, and clot retraction in human-washed platelets. In summary, this research provides pioneering evidence that 6-OHDA induces abnormal platelet functions, shedding light on the previously unexplored processes by which 6-OHDA affects platelet activity.
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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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Ketamine is a widely used clinical drug that has several functional and clinical applications, including its use as an anaesthetic, analgesic, anti-depressive, anti-suicidal agent, among others. Among its diverse behavioral effects, it influences short-term memory and induces psychedelic effects. At the neural level across different brain areas, it modulates neural firing rates, neural tuning, brain oscillations, and modularity, while promoting hypersynchrony and random connectivity between neurons. ⋯ This model has potential implications for focused modulation of cortical networks in clinical settings. Finally, we identify current gaps in research and suggest directions for future studies, particularly emphasizing the need for more animal experiments to establish a platform for effective translation and synergistic therapies combining ketamine with other protocols such as training and adaptation. In summary, investigating ketamine's broader systemic effects, not only provides deeper insight into cognitive functions and consciousness but also paves the way to advance therapies for neuropsychiatric disorders.