The neural underpinnings of processing concrete and abstract semantics remain poorly understood. Previous fMRI studies have shown that multimodal and amodal neural networks respond differentially to different semantic types; importantly, abstract semantics activates more left-lateralized networks, as opposed to more bilateral activity for concrete words. Due to the lack of temporal resolution, these fMRI results do not allow to easily separate language- and task-specific brain responses and to disentangle early processing stages from later post-comprehension phenomena.
View Article and Find Full Text PDFWorking memory (WM) is the cognitive ability to store and manipulate information necessary for ongoing tasks. Although frontoparietal areas are involved in the retention of visually presented information, oscillatory neural activity differs for temporal and spatial WM processing. In this study, we corroborated previous findings describing the modulation of neural oscillations and expanded our investigation to the network organization underlying the cognitive processing of temporal and spatial information.
View Article and Find Full Text PDFTissue regeneration requires coordination between resident stem cells and local niche cells. Here we identify that senescent cells are integral components of the skeletal muscle regenerative niche that repress regeneration at all stages of life. The technical limitation of senescent-cell scarcity was overcome by combining single-cell transcriptomics and a senescent-cell enrichment sorting protocol.
View Article and Find Full Text PDFCellular senescence is a stable type of cell cycle arrest triggered by different stresses. As such, senescence drives age-related diseases and curbs cellular replicative potential. Here, we show that 3-deazaadenosine (3DA), an S-adenosyl homocysteinase (AHCY) inhibitor, alleviates replicative and oncogene-induced senescence.
View Article and Find Full Text PDFCellular senescence is a state of irreversible cell cycle arrest that often emerges after tissue damage and in age-related diseases. Through the production of a multicomponent secretory phenotype (SASP), senescent cells can impact the regeneration and function of tissues. However, the effects of senescent cells and their SASP are very heterogeneous and depend on the tissue environment and type as well as the duration of injury, the degree of persistence of senescent cells and the organism's age.
View Article and Find Full Text PDFFront Neural Circuits
January 2022
According to mechanistic theories of working memory (WM), information is retained as stimulus-dependent persistent spiking activity of cortical neural networks. Yet, how this activity is related to changes in the oscillatory profile observed during WM tasks remains a largely open issue. We explore joint effects of input gamma-band oscillations and noise on the dynamics of several firing rate models of WM.
View Article and Find Full Text PDFIt remains challenging to generate reproducible, high-quality cDNA libraries from RNA derived from rare cell populations. Here, we describe a protocol for high-throughput RNA-seq library preparation, including isolation of 200 skeletal muscle stem cells from mouse tibialis anterior muscle by fluorescence-activated cell sorting and cDNA preparation. We also describe RNA extraction and cDNA preparation from differentiating mouse embryonic stem cells.
View Article and Find Full Text PDFBoth human and animal studies have demonstrated remarkable findings of experience-induced plasticity in the cortex. Here, we investigated whether the widely used monetary incentive delay (MID) task changes the neural processing of incentive cues that code expected monetary outcomes. We used a novel auditory version of the MID task, where participants responded to acoustic cues that coded expected monetary losses.
View Article and Find Full Text PDFNumerous cognitive studies have demonstrated experience-induced plasticity in the primary sensory cortex, indicating that repeated decisions could modulate sensory processing. In this context, we investigated whether an auditory version of the monetary incentive delay (MID) task could change the neural processing of the incentive cues that code expected monetary outcomes. To study sensory plasticity, we presented the incentive cues as deviants during oddball sessions recorded before and after training in the two MID task sessions.
View Article and Find Full Text PDFThe maintenance of adult stem cells in their normal quiescent state depends on intrinsic factors and extrinsic signals originating from their microenvironment (also known as the stem cell niche). In skeletal muscle, its stem cells (satellite cells) lose their regenerative potential with aging, and this has been attributed, at least in part, to both age-associated changes in the satellite cells as in the niche cells, which include resident fibro-adipogenic progenitors (FAPs), macrophages, and endothelial cells, among others. To understand the regenerative decline of skeletal muscle with aging, there is a need for methods to specifically isolate stem and niche cells from resting muscle.
View Article and Find Full Text PDFDopamine (DA) neurons in the ventral tegmental area (VTA) are thought to encode reward prediction errors (RPE) by comparing actual and expected rewards. In recent years, much work has been done to identify how the brain uses and computes this signal. While several lines of evidence suggest the interplay of the DA and the inhibitory interneurons in the VTA implements the RPE computation, it still remains unclear how the DA neurons learn key quantities, for example the amplitude and the timing of primary rewards during conditioning tasks.
View Article and Find Full Text PDFAlthough the first experiments on alpha-neurofeedback date back nearly six decades ago, when Joseph Kamiya reported successful operant conditioning of alpha-rhythm in humans, the effectiveness of this paradigm in various experimental and clinical settings is still a matter of debate. Here, we investigated the changes in EEG patterns during a continuously administered neurofeedback of P4 alpha activity. Two days of neurofeedback training were sufficient for a significant increase in the alpha power to occur.
View Article and Find Full Text PDFHumans often adjust their opinions to the perceived opinions of others. Neural responses to a perceived match or mismatch between individual and group opinions have been investigated previously, but some findings are inconsistent. In this study, we used magnetoencephalographic source imaging to investigate further neural responses to the perceived opinions of others.
View Article and Find Full Text PDFWhile variability of the motor responses to transcranial magnetic stimulation (TMS) is widely acknowledged, little is known about its central origin. One plausible explanation for such variability may relate to different neuronal states defining the reactivity of the cortex to TMS. In this study intrinsic spatio-temporal neuronal dynamics were estimated with Long-Range Temporal Correlations (LRTC) in order to predict the inter-individual differences in the strength of intra-cortical facilitation (ICF) and short-interval intracortical inhibition (SICI) produced by paired-pulse TMS (ppTMS) of the left primary motor cortex.
View Article and Find Full Text PDFIntroduction: Amyotrophic lateral sclerosis (ALS) is a motor neuron disease with a gender bias towards major prevalence in male individuals. Several data suggest the involvement of oxidative stress and mitochondrial dysfunction in its pathogenesis, though differences between genders have not been evaluated. For this reason, we analysed features of mitochondrial oxidative metabolism, as well as mitochondrial chain complex enzyme activities and protein expression, lipid profile, and protein oxidative stress markers, in the Cu,Zn superoxide dismutase with the G93A mutation (hSOD1-G93A)- transgenic mice and Neuro2A(N2A) cells overexpressing hSOD1-G93A.
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