Neuroscience
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Pragmatic competence demands linguistic, but also communicative, social and cognitive competence. Successful use of language in social interaction requires mutual understanding of the speaker's intentions; without it, a conversation cannot proceed. The term speech act refers to what a speaker intends to accomplish when saying something. ⋯ The recognition of speech acts resulted in greater activation of frontal regions, precuneus and posterior cingulate gyrus. From all cognitive and behavioral measures obtained, only the scores in mental flexibility predicted the change in blood oxygen level dependent (BOLD) signal in the precuneus. These results, support the idea that speech act recognition requires the inference of intention, executive functions, including memory and entails the activation of areas of social cognition that participate in several brain networks i.e., the Intention Processing, the Default Mode and Theory of Mind networks, and areas involved in planning and guiding behavior.
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Little is known about how the aberrant structural and functional connectivity relates to the rapid ejaculation. Data of diffusion tensor imaging and resting state functional magnetic resonance imaging were acquired from 32 PE patients and 38 healthy controls (HCs). Firstly, we investigated the structural connectivity (SC) disruptions of PE patients using the method of graph theoretical analysis. ⋯ FC analysis revealed that PE patients had decreased FC values in the default mode network, visual recognition network and subcortical network, as well as increased FC values in the attention network. Moreover, correlation analysis revealed that the nodal strength of right superior frontal gyrus (dorsolateral) was negatively associated with the intra-vaginal ejaculation latency, while FC values between the left middle frontal gyrus and middle occipital gyrus were positively related to the total scores of the premature ejaculation diagnostic tool (PEDT). Our results indicated that PE might be associated with the abnormal SC of areas in the prefrontal-amygdala pathway and aberrant FC in certain functional brain networks, especially in default mode network.
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Selective serotonin reuptake inhibitor (SSRI) antidepressants are widely prescribed to pregnant women suffering with depression, although the long-term impact of these medications on exposed offspring are poorly understood. Perinatal SSRI exposure alters human offspring's neurodevelopment and increases risk for psychiatric illness in later life. Rodent studies suggest that perinatal SSRI-induced behavioral abnormalities are driven by changes in the serotonin system as well as epigenetic and transcriptomic changes in the developing hippocampus. ⋯ To determine translational implications of this work, we examined expression of BAI3 and related molecules in hippocampus and prefrontal cortex from patients that suffered with depression or schizophrenia relative to healthy control subjects. We found sex- and region-specific changes in mRNA expression of BAI3 and its ligands C1QL2 and C1QL3 in men and women with a history of psychiatric disorders compared to healthy controls. Together these results suggest that abnormal BAI3 signaling may contribute to molecular mechanisms that drive adverse effects of perinatal SSRI exposure, and show evidence for alterations of BAI3 signaling in the hippocampus of patients that suffer depression and schizophrenia.
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Voltage-gated Ca2+ (CaV) channels regulate multiple cell processes, including neurotransmitter release, and have been associated with several pathological conditions, such as neuropathic pain. Cdk5, a neuron-specific kinase, may phosphorylate CaV channels, altering their functional expression. During peripheral nerve injury, upregulation of CaV channels and Cdk5 in the dorsal root ganglia (DRG) and the spinal cord, has been correlated with allodynia. ⋯ Likewise, the Cdk5 inhibitor olomoucine affected the rapid and the slow C components of the cAP recorded in the dorsal roots. Patch-clamp recordings revealed an increase in T- and N-type currents recorded in the soma of acute isolated L3-4 sensory neurons after L5-6 SNL, which was prevented by olomoucine. These findings suggest changes in CaV channels location and function in L3-4 afferent fibers associated with Cdk5-mediated phosphorylation after L5-6 SNL, which may contribute to nerve injury-induced allodynia.
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Sleep deprivation critically affects vigilant attention. Previous neuroimaging studies have revealed altered inter-regional functional connectivity after sleep deprivation, which may disrupt topological properties of brain functional networks. However, little is known about alterations in the topology of intrinsic connectivity and its involvement in attention performance after sleep deprivation. ⋯ At the nodal level, the altered regions were selectively distributed in frontoparietal networks, sensorimotor networks, temporal regions, and salience networks. More specifically, the altered clustering coefficient in the posterior superior temporal sulcus (pSTS) and insula, and altered local efficiency in pSTS were further associated with PVT performance after TSD. Our results suggest that the topological properties of brain functional networks are disrupted, and aberrant topology of temporal networks and salience networks may act as neural signatures underlying the vigilant attention impairments after TSD.