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排序方式: 共有2712条查询结果,搜索用时 15 毫秒
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Hajrunisa Cubro Karl A. Nath Sonja Suvakov Oscar Garcia-Valencia Santosh Parashuram Wendy M. White Tracey L. Weissgerber Meryl C. Nath Natasa M. Milic Fernando Sontag Livius V. d’Uscio Yi Zhu James L. Kirkland Tamar Tchkonia Mariam P. Alexander Reade A. Quinton Zvonimir S. Katusic Joseph P. Grande Vesna D. Garovic 《Kidney international》2021,99(3):646-656
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Martine M. Groefsema Gabry W. Mies Janna Cousijn Rutger C. M. E. Engels Guillaume Sescousse Maartje Luijten 《The European journal of neuroscience》2020,51(6):1491-1503
Alcohol is mainly consumed in social settings, in which people often adapt their drinking behaviour to that of others, also called imitation of drinking. Yet, it remains unclear what drives this drinking in a social setting. In this study, we expected to see stronger brain and behavioural responses to social compared to non‐social alcohol cues, and these responses to be associated with drinking in a social setting. The sample consisted of 153 beer‐drinking males, aged 18–25 years. Brain responses to social alcohol cues were measured during an alcohol cue‐exposure task performed in an fMRI scanner. Behavioural responses to social alcohol cues were measured using a stimulus‐response compatibility task, providing an index of approach bias towards these cues. Drinking in a social setting was measured in a laboratory mimicking a bar environment. Specific brain responses to social alcohol cues were observed in the bilateral superior temporal sulcus and the left inferior parietal lobe. There was no approach bias towards social alcohol cues specifically; however, we did find an approach bias towards alcohol (versus soda) cues in general. Brain responses and approach bias towards social alcohol cues were unrelated and not associated with actual drinking. Thus, we found no support for a relation between drinking in a social setting on the one hand, and brain cue‐reactivity or behavioural approach biases to social alcohol cues on the other hand. This suggests that, in contrast to our hypothesis, drinking in a social setting may not be driven by brain or behavioural responses to social alcohol cues. 相似文献
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《Archives of Cardiovascular Diseases》2020,113(4):263-275
The difficult balance between thrombosis and bleeding after transcatheter aortic valve replacement. TAVR: transcatheter aortic valve replacement. 相似文献
6.
Sinéad Lydon Phil Reed Teresa Mulhern Brian M. Hughes Matthew S. Goodwin 《Developmental neurorehabilitation》2016,19(6):335-355
Objective: The prevalence of abnormal behavioural responses to a variety of stimuli among individuals with autism has led researchers to examine whether physiological reactivity (PR) is typical in this population. This article reviewed studies assessing PR to sensory, social and emotional, and stressor stimuli in individuals with autism. Methods: Systematic searches of electronic databases identified 57 studies that met our inclusion criteria. Studies were analysed to determine: (a) participant characteristics; (b) physiological measures used; (c) PR to sensory, social and emotional or stressor stimuli; (d) the relation between PR and behavioural or psychological variables and (e) baseline physiological activity. A novel measure of methodological quality suitable for use with non-randomized, non-interventional, psychophysiological studies was also developed and applied. Results: Individuals with autism were found to respond differently than typically developing controls in 78.6%, 66.7% and 71.4% of sensory, social and emotional, and stressor stimulus classes, respectively. However, this extant literature is characterized by variable and inconsistent findings, which do not appear to be accounted for by varying methodological quality, making it difficult to determine what specific factors differentiate individuals with autism who present with atypical PR from those who do not. Conclusions: Despite this uncertainty, individual differences in PR are clearly present in autism, suggesting additional research is needed to determine the variables relating to PR among those with ASD and to examine the possible existence of physiological subtype responders in the population. 相似文献
7.
Jeroen C. W. Siero Megan K. Strother Carlos C. Faraco Hans Hoogduin Jeroen Hendrikse Manus J. Donahue 《NMR in biomedicine》2015,28(11):1518-1525
Normocapnic hyperoxic and hypercapnic hyperoxic gas challenges are increasingly being used in cerebrovascular reactivity (CVR) and calibrated functional MRI experiments. The longitudinal arterial blood water relaxation time (T1a) change with hyperoxia will influence signal quantification through mechanisms relating to elevated partial pressure of plasma‐dissolved O2 (pO2) and increased oxygen bound to hemoglobin in arteries (Ya) and veins (Yv). The dependence of T1a on Ya and Yv has been elegantly characterized ex vivo; however, the combined influence of pO2, Ya and Yv on T1a in vivo under normal ventilation has not been reported. Here, T1a is calculated during hyperoxia in vivo by a heuristic approach that evaluates T1‐dependent arterial spin labeling (ASL) signal changes to varying gas stimuli. Healthy volunteers (n = 14; age, 31.5 ± 7.2 years) were scanned using pseudo‐continuous ASL in combination with room air (RA; 21% O2/79% N2), hypercapnic normoxic (HN; 5% CO2/21% O2/74% N2) and hypercapnic hyperoxic (HH; 5% CO2/95% O2) gas administration. HH T1a was calculated by requiring that the HN and HH cerebral blood flow (CBF) change be identical. The HH protocol was then repeated in patients (n = 10; age, 61.4 ± 13.3 years) with intracranial stenosis to assess whether an HH T1a decrease prohibited ASL from being performed in subjects with known delayed blood arrival times. Arterial blood T1a decreased from 1.65 s at baseline to 1.49 ± 0.07 s during HH. In patients, CBF values in the affected flow territory for the HH condition were increased relative to baseline CBF values and were within the physiological range (RA CBF = 36.6 ± 8.2 mL/100 g/min; HH CBF = 45.2 ± 13.9 mL/100 g/min). It can be concluded that hyperoxic (95% O2) 3‐T arterial blood T1aHH = 1.49 ± 0.07 s relative to a normoxic T1a of 1.65 s. Copyright © 2015 John Wiley & Sons, Ltd. 相似文献
8.
Ronny Redlich Ilona Schneider Nicole Kerkenberg Nils Opel Jonas Bauhaus Verena Enneking Jonathan Repple Elisabeth J. Leehr Dominik Grotegerd Claas Khler Katharina Frster Katharina Dohm Susanne Meinert Tim Hahn Harald Kugel Kathrin Schwarte Christiane Schettler Katharina Domschke Volker Arolt Walter Heindel Bernhard T. Baune Weiqi Zhang Christa Hohoff Udo Dannlowski 《Human brain mapping》2020,41(3):594-604
Epigenetic alterations of the brain‐derived neurotrophic factor (BDNF) gene have been associated with psychiatric disorders in humans and with differences in amygdala BDNF mRNA levels in rodents. This human study aimed to investigate the relationship between the functional BDNF‐Val66Met polymorphism, its surrounding DNA methylation in BDNF exon IX, amygdala reactivity to emotional faces, and personality traits. Healthy controls (HC, n = 189) underwent functional MRI during an emotional face‐matching task. Harm avoidance, novelty seeking and reward dependence were measured using the Tridimensional Personality Questionnaire (TPQ). Individual BDNF methylation profiles were ascertained and associated with several BDNF single nucleotide polymorphisms surrounding the BDNF‐Val66Met, amygdala reactivity, novelty seeking and harm avoidance. Higher BDNF methylation was associated with higher amygdala reactivity (x = 34, y = 0, z = ?26, t(166) = 3.00, TFCE = 42.39, p(FWE) = .045), whereby the BDNF‐Val66Met genotype per se did not show any significant association with brain function. Furthermore, novelty seeking was negatively associated with BDNF methylation (r = ?.19, p = .015) and amygdala reactivity (r = ?.17, p = .028), while harm avoidance showed a trend for a positive association with BDNF methylation (r = .14, p = .066). The study provides first insights into the relationship among BDNF methylation, BDNF genotype, amygdala reactivity and personality traits in humans, highlighting the multidimensional relations among genetics, epigenetics, and neuronal functions. The present study suggests a possible involvement of epigenetic BDNF modifications in psychiatric disorders and related brain functions, whereby high BDNF methylation might reduce BDNF mRNA expression and upregulate amygdala reactivity. 相似文献
9.
《Brain stimulation》2021,14(2):304-315
BackgroundSingle-pulse transcranial magnetic stimulation (TMS) elicits an evoked electroencephalography (EEG) potential (TMS-evoked potential, TEP), which is interpreted as direct evidence of cortical reactivity to TMS. Thus, combining TMS with EEG can be used to investigate the mechanism underlying brain network engagement in TMS treatment paradigms. However, controversy remains regarding whether TEP is a genuine marker of TMS-induced cortical reactivity or if it is confounded by responses to peripheral somatosensory and auditory inputs. Resolving this controversy is of great significance for the field and will validate TMS as a tool to probe networks of interest in cognitive and clinical neuroscience.ObjectiveHere, we delineated the cortical origin of TEP by spatially and temporally localizing successive TEP components, and modulating them with transcranial direct current stimulation (tDCS) to investigate cortical reactivity elicited by single-pulse TMS and its causal relationship with cortical excitability.MethodsWe recruited 18 healthy participants in a double-blind, cross-over, sham-controlled design. We collected motor-evoked potentials (MEPs) and TEPs elicited by suprathreshold single-pulse TMS targeting the left primary motor cortex (M1). To causally test cortical and corticospinal excitability, we applied tDCS to the left M1.ResultsWe found that the earliest TEP component (P25) was localized to the left M1. The following TEP components (N45 and P60) were largely localized to the primary somatosensory cortex, which may reflect afferent input by hand-muscle twitches. The later TEP components (N100, P180, and N280) were largely localized to the auditory cortex. As hypothesized, tDCS selectively modulated cortical and corticospinal excitability by modulating the pre-stimulus mu-rhythm oscillatory power.ConclusionTogether, our findings provide causal evidence that the early TEP components reflect cortical reactivity to TMS. 相似文献
10.
To understand the influence of social relationships on cardiovascular responses to stress, the present study investigated perceived affectionate support as a mediating variable explaining the association between specific attachment bonds (i.e., mother, father, partner, best friend) and cardiovascular reactivity (CVR). Utilizing a standardized stress testing protocol, 138 young adults completed measures of attachment and social support, with continuous cardiovascular measurements obtained using the Finometer Pro hemodynamic monitor. Results showed that the association between anxious and avoidant attachment and reactivity were mediated by perceived affectionate support; insecure attachment was linked to lower levels of perceived social support, which in turn was associated with lower CVR. For anxious attachment, this was noted only for mothers (SBP: B = −0.94, 95% CI [−1.94, −0.20]; DBP: B = −0.57, [−1.27, −0.10]), fathers (SBP: B = −0.72, [−1.42, −0.17]; DBP: B = −0.48, [−1.01, −0.13]), and best friends (SBP: B = −0.64, [−1.23, −0.18]; DBP: B = −0.40, [−0.81, −0.12]). For avoidant attachment, it was evident only for fathers (SBP: B = −0.70, [−1.33, −0.17]; DBP: B = −0.48, [−0.92, −0.15]) and partners (SBP: B = −0.78, [−1.64, −0.09]; DBP: B = −0.53, [−1.10, −0.11]). These findings suggest that insecure attachment is associated with lower levels of reactivity, which have been linked to negative health outcomes such as poor self-reported health, depression, and obesity. Overall, this research expands on the support and relationship science literature by incorporating under-researched aspects of social relationships (i.e., specific attachment styles) and focusing on the mechanisms by which they are associated with physiological stress responses. 相似文献