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91.
Normal aging is associated with cognitive decline and underlying brain dysfunction. Previous studies concentrated less on brain network changes at a systems level. Our goal was to examine these age-related changes of fMRI-derived activation with a common network parcellation of the human brain function, offering a systems-neuroscience perspective of healthy aging. We conducted a series of meta-analyses on a total of 114 studies that included 2035 older adults and 1845 young adults. Voxels showing significant age-related changes in activation were then overlaid onto seven commonly referenced neuronal networks. Older adults present moderate cognitive decline in behavioral performance during fMRI scanning, and hypo-activate the visual network and hyper-activate both the frontoparietal control and default mode networks. The degree of increased activation in frontoparietal network was associated with behavioral performance in older adults. Age-related changes in activation present different network patterns across cognitive domains. The systems neuroscience approach used here may be useful for elucidating the underlying network mechanisms of various brain plasticity processes during healthy aging. 相似文献
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《The journal of sexual medicine》2015,12(4):946-955
IntroductionDespite the high prevalence of hypoactive sexual desire disorder (HSDD), especially among women, this sexual disorder remains poorly understood. Among the multiple factors possibly involved in HSDD, particularities in the cognitive evaluations of social stimuli need to be better characterized. Especially, beauty and attractiveness judgments, two dimensions of interpersonal perception that are related but differ on their underlying motivational aspects, may vary according to the level of sexual desire.AimThe main goal of this study was to investigate whether women with and without HSDD differ in their evaluations of beauty and attractiveness of men's faces and voices.MethodsYoung women from the general population (controls, n = 16) and with HSDD (patients, n = 16) took part in the study. They were presented with a series of neutral/nonerotic voices and faces of young men from the GEneva Faces And Voices database.Main Outcome MeasuresRatings of beauty (i.e., assessments of aesthetic pleasure) and of attractiveness (i.e., assessments of the personal propensity to feel attracted to someone) and the frequency to which the participants pressed a key to see or listen to each stimulus again were the main outcome measures.ResultsRatings of attractiveness were lower than ratings of beauty in both groups of women. The dissociation between beauty and attractiveness was larger in women with HSDD than in control participants. Patients gave lower attractiveness ratings than the controls and replayed the stimuli significantly less often.ConclusionThese results suggest that women with HSDD are characterized by specific alterations of the motivational component of men's perception, very early in the process of interpersonal relationships. Our findings have significant implications, both in better understanding the specific cognitive processes underlying hypoactive sexual desire and more largely the evaluative processes involved in human mate choice. Ferdenzi C, Delplanque S, Vorontsova-Wenger O, Pool E, Bianchi-Demicheli F, and Sander D. Perception of men's beauty and attractiveness by women with low sexual desire. J Sex Med 2015;12:946–955. 相似文献
94.
Restricted and repetitive behaviors (RRBs) constitute a core symptom of autism spectrum disorder (ASD). The Repetitive Behavior Scale-Revised (RBS-R) is a widely used questionnaire administered by parents or caregivers to assess RRBs in individuals with ASD. This study evaluated the psychometric properties of the RBS-R Japanese Version (RBS-R-J). The ASD and non-ASD groups comprised 274 and 36 participants, respectively. We examined corrected item-total correlation, Cronbach's alpha, and RBS-R-J scores of different diagnostic groups, as well as correlations between RBS-R-J scores and intelligence quotient (IQ), autistic symptoms, adaptive/maladaptive functioning, aberrant behaviors, and sensory processing. All items showed moderate corrected item-total correlations. Cronbach's alpha coefficient was .93. We found significant differences in the mean RBS-R-J scores of the low-functioning ASD group and the intellectual disabilities group, and of low-functioning and high-functioning ASD groups. RBS-R-J scores negatively correlated with IQ and scores on the Sensory Profile (Japanese version) and Adaptive Behavior Composite of the Maladaptive Behavior Index of the Vineland Adaptive Behavior Scales-Second Edition (VABS-II; Japanese version), but positively correlated with scores on the peak and current symptoms subscales of the Pervasive Developmental Disorders Autism Society Japan Rating Scale, the VABS-II, and the Aberrant Behavior Checklist-Community (Japanese version). From these results, we conclude that RBS-R-J showed good reliability, diagnostic validity, and convergent validity, indicating that it is a reliable, valid instrument for use among ASD individuals in clinical and research settings. 相似文献
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The discovery and validation of biomarkers in neurological and neurodegenerative diseases is an important challenge for early diagnosis of disease and for the development of therapeutics. Epilepsy is often a consequence of brain insults such as traumatic brain injury or stroke, but as yet no biomarker exists to predict the development of epilepsy in patients at risk. Given the complexity of epilepsy, it is unlikely that a single biomarker is sufficient for this purpose, but a combinatorial approach may be needed to overcome the challenge of individual variability and disease heterogeneity. The goal of the present prospective study in the lithium–pilocarpine model of epilepsy in rats was to determine the discriminative utility of combinations of phenotypic biomarkers by examining their ability to predict epilepsy. For this purpose, we used a recent model refinement that allows comparing rats that will or will not develop spontaneous recurrent seizures (SRS) after pilocarpine-induced status epilepticus (SE). Potential biomarkers included in our study were seizure threshold and seizure severity in response to timed i.v. infusion of pentylenetetrazole (PTZ) and behavioral alterations determined by a battery of tests during the three weeks following SE. Three months after SE, video/EEG monitoring was used to determine which rats had developed SRS. To determine whether a biomarker or combination of biomarkers performed better than chance at predicting epilepsy after SE, derived data underwent receiver operating characteristic (ROC) curve analyses. When comparing rats with and without SRS and sham controls, the best intergroup discrimination was obtained by combining all measurements, resulting in a ROC area under curve (AUC) of 0.9592 (P < 0.01), indicating an almost perfect discrimination or accuracy to predict development of SRS. These data indicate that a combinatorial biomarker approach may overcome the challenge of individual variability in the prediction of epilepsy. 相似文献
97.
The analgesic effects of gastrodin (GAS), an active component derived from the Chinese herb Tian ma (Gastrodia elata Blume), on chronic inflammatory pain of mice and the involved molecular mechanisms were investigated. GAS significantly attenuated mice chronic inflammatory pain induced by hindpaw injection of complete Freund's adjuvant (CFA) and the accompanying anxiety-like behaviors. GAS administration reduced CFA-induced up-regulation of GluR1-containing α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid (AMPA) receptors, GluN2A- and GluN2B-containing N-methyl-d-aspartate (NMDA) receptors, and Ca2 +/calmodulin-dependent protein kinase II-alpha (CaMKII-α) in the anterior cingulate cortex (ACC). The GluN2A and GluN2B subunits of NMDA receptors, the GluR1 type of AMPA receptor, and CaMKII-α are key molecules responsible for neuroplasticity involved in chronic pain and the accompanying anxiety. Moreover, GAS administration reduced the activation of astrocyte and microglia and the induction of TNF-α and IL-6 in the ACC of the CFA-injected mice. Therefore, GAS administration relieved chronic pain, exerted anxiolytic effects by regulating neuroplasticity molecules, and attenuated the inflammatory response by reducing the induction of TNF-α and IL-6 in the ACC of the CFA-injected mice. 相似文献
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《The journal of sexual medicine》2022,19(6):1035-1048
BackgroundRecently, the variability and heterogeneity of gender presentations in transgender youths have gained significant attention worldwide. Alongside this, specialized gender services have reported an increase in referrals of youths reporting non-binary identities. In Italy, studies investigating gender identity and expression in gender non-conforming youths are lacking, as are data regarding the non-binary population.AimThe present study aimed at dimensionally exploring how transgender and non-binary Italian adolescents identify and express their gender.OutcomesGender expression in trans binary youths and non-binary youths.MethodsThe Gender Diversity Questionnaire (GDQ; Twist & de Graaf, 2019) was used to investigate gender identity, gender fluidity, and gender expression in a sample of 125 adolescent patients from the Gender Identity Development Service (SAIFIP) in Rome and the Gender Incongruence Unit of the Careggi Hospital in Florence, between April 2019–June 2021.ResultsThe majority of participants (74.4%) identified as trans* binary and the remaining (25.6%) participants identified as non-binary. Trans binary participants reported a stable gender identity, whereas non-binary participants reported a more fluid gender identity across time and contexts. Almost all participants rated external appearance as important to their gender expression, yet trans binary participants attributed more importance to the body in this respect. Body discomfort and pubertal stage emerged as the most influential factors in participants’ experiences of gender. Participants who were assigned male at birth expressed significantly more desire for puberty blockers, whereas those who were assigned female at birth had a stronger desire to engage in breast/chest surgery. Non-binary participants sought different medical interventions relative to trans binary participants.Clinical ImplicationsThese results may be useful for clinicians working with transgender youths as they provide awareness regarding the features of young people who identify within and outside of binary constructions of gender.Strengths & LimitationsThis study provides useful data in gaining insight into understanding the variety of experiences and challenges of gender non-conforming youths. However as the sample was recruited from specialized services, it may not represent the entire gender non-conforming population in Italy.ConclusionThe results describe the range of gender identities and expressions among gender non-conforming youths attending gender specialized services in Italy, thereby improving our understanding of the variety of identities experienced and the specific medical needs of both trans binary and non-binary adolescents.Mirabella M, Piras I, Fortunato A, et al. Gender Identity and Non-Binary Presentations in Adolescents Attending Two Specialized Services in Italy. J Sex Med 2022;19:1035–1048. 相似文献