Neuroscience
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The chronic neuropathic pain-associated psychiatric disorders have seriously disturbed the quality of patients' life, such as depression and anxiety. Neuroinflammation in the hippocampus plays an important role in the neuropathic pain-associated depressive and anxiety disorders, but the underlying mechanism has not been thoroughly elucidated to date. The Nod-like receptor protein (NLRP)-1 inflammasome, which controls the production of pro-inflammatory cytokines, was broadly involved in the neuroinflammation-related diseases. ⋯ Functional inhibition of PKR suppressed the NLRP1 inflammasome activation and effectively attenuated the CCI-induced depression-like behaviors. These results indicate that the hippocampal PKR/NLRP1 inflammasome pathway play an important role in the development of the depressive behaviors after chronic neuropathic pain. Thus, interrupting this pathway might provide a novel therapeutic strategy for neuropathic pain-associated depressive disorders.
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How is motor learning affected by aging? Although several experimental paradigms have been used to address this question, there has been limited focus on the early phase of motor learning, which involves motor exploration and the need to coordinate multiple degrees of freedom in the body. Here, we examined motor learning in a body-machine interface where we measured both age-related differences in task performance as well as the coordination strategies underlying this performance. Participants (N = 65; age range 18-72 years) wore wireless inertial measurement units on the upper body, and learned to control a cursor on a screen, which was controlled by motions of the trunk. ⋯ However, we also found that these changes were associated with limited exploration in older adults. Moreover, when considering data across a majority of the lifespan (including children), longer movement times were associated with greater inefficiency of the coordination pattern, producing more task-irrelevant motion. These results suggest exploration behaviors during motor learning are affected with aging, and highlight the need for different practice strategies with aging.
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To foster performance across all levels of sports practice, physical training has been integrated with various mental training practices. Recently, an integrative approach to neurocognitive enhancement tried to combine the strengths of mental practices (i.e. mindfulness) and of training with neurofeedback devices. Based on previous validation studies showing the effect of a combined mindfulness-neurofeedback program on neurocognitive efficiency and stress/anxiety levels, we aimed at testing the feasibility and potential of that intensive combined program for improving psychological well-being and attention regulation in sport contexts. 50 participants (sportspeople and volunteers not regularly involved in sports) were divided into groups undergoing experimental and active control training programs. ⋯ We have also observed a general reduction of perceived stress and increased ability to keep a non-evaluative stance. Findings extend available observations on cognitive and neural effects of combined mindfulness-neurofeedback practice by showing that it is possible to observe training effects even after a limited period of practice among sportspeople. Such early training effects might mirror optimized implicit learning curves due to peculiar sensitivity to bodily signals and awareness.
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Spatially separated brain areas interact with each other to form networks with coordinated activities, supporting various brain functions. Interaction structures among brain areas have been widely investigated through pairwise measures. However, interactions among multiple (e.g., triple and quadruple) areas cannot be reduced to pairwise interactions. ⋯ We found that HOI strength in the macroscopic functional networks was very weak for all tasks, suggesting that major brain activities do not rely on HOIs on the macroscopic level at the timescale of hundreds of milliseconds. These weak HOIs during tasks were further investigated with a neural network model activated by external inputs, which suggested that weak pairwise interactions among brain areas organized the system without involving HOIs. Taken together, these results demonstrated the dominance of pairwise interactions in organizing coordinated activities among different brain areas to support various brain functions.
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High voltage-activated (HVA) Ca2+ (CaV) channels are oligomeric complexes formed by an ion-conducting main subunit (Cavα1) and at least two auxiliary subunits (Cavβ and CaVα2δ). It has been reported that the expression of CaVα2δ1 increases in the dorsal root ganglia (DRGs) of animals with mechanical allodynia, and that the transcription factor Sp1 regulates the expression of the auxiliary subunit. Hence, the main aim of this work was to investigate the role of Sp1 as a molecular determinant of the exacerbated expression of CaVα2δ-1 in the nerve ligation-induced model of mechanical allodynia. ⋯ Interestingly, intrathecal administration of the Sp1 inhibitor mithramycin A (Mth) prevented allodynia and decreased the expression of Sp1 and CaVα2δ-1. Likewise, electrophysiological recordings showed that incubation with Mth decreased Ca2+ current density in the DRG neurons, acting mostly on HVA channels. These results suggest that L5/L6 SNL produces mechanical allodynia and increases the expression of the transcription factor Sp1 and the subunit CaVα2δ-1 in the DRGs, while Mth decreases mechanical allodynia and Ca2+ currents through HVA channels in sensory neurons by reducing the functional expression of the CaVα2δ-1 subunit.