Neuroscience
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Identifying printed words and pictures concurrently is ubiquitous in daily tasks, and so it is important to consider the extent to which reading words and naming pictures may share a cognitive-neurophysiological functional architecture. Two functional magnetic resonance imaging (fMRI) experiments examined whether reading along the left ventral occipitotemporal region (vOT; often referred to as a visual word form area, VWFA) has activation that is overlapping with referent pictures (i.e., both conditions significant and shared, or with one significantly more dominant) or unique (i.e., one condition significant, the other not), and whether picture naming along the right lateral occipital complex (LOC) has overlapping or unique activation relative to referent words. ⋯ Experiment 2 controlled for visual complexity by superimposing the words and pictures and instructing participants to either name the word or the picture, and showed primarily shared activation in the VWFA and LOC regions for both word reading and picture naming, with some dominant activation for pictures in the LOC. Overall, these results highlight the importance of including exception words to force lexical reading when comparing to picture naming, and the significant shared activation in VWFA and LOC serves to challenge specialized models of reading or picture naming.
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Central poststroke pain (CPSP) is a neuropathic pain syndrome that usually occurs after cerebrovascular accidents. Currently, the pathogenesis of CPSP is not fully understood. Purinergic P2X4 receptor (P2X4R) is implicated in neuropathic pain including CPSP. ⋯ This mechanism was associated with P2X4R expression and involved the endogenous opioid system. Human patients with CPSP showed decreased plasma levels of miR-133b-3p compared with those of control participants. Logistic regression analysis of our patient cohort showed that determining plasma levels of miR-133b-3p may be useful for CPSP diagnosis and treatment.
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Presbycusis, or age-related hearing loss (ARHL), is primarily associated with sensory or transduction nerve cell degeneration in the peripheral and/or central auditory systems. During aging, the auditory system shows mitochondrial dysfunction and increased inflammatory responses. Mitochondrial dysfunction promotes leakage of mitochondrial DNA (mtDNA) into the cytosol, which activates the cyclic GMP-AMP synthase (cGAS)-stimulator of interferon genes (STING) pathway to induce type I interferon and inflammatory responses. ⋯ The results showed that cGAS-positive immunoreactive cells were observed in the cochlea, inferior colliculus, and auditory cortex. Levels of cytosolic mtDNA, cGAS, STING, phosphorylated interferon regulatory factor 3, and cytokines were significantly increased in the cochlea, inferior colliculus, and auditory cortex of 6-, 9-, and 12-month-old mice compared with 3-month-old mice. These findings suggested that cytosolic mtDNA may play an important role in the pathogenesis of ARHL by activating cGAS-STING-mediated type I interferon and inflammatory responses.