Magnetic-field dependence of nucleation undercoolings in non-magnetic metallic melts

The nucleation undercoolings of non-magnetic metals like paramagnetic aluminium in high magnetic fields were measured by the differential thermal analysis technique. It was shown that the nucleation undercooling of pure aluminium increased with increasing the magnetic field, while its melting temperature was hardly changed. Based on the model of magnetic dipoles at the interface, it is proposed that the magnetic-field-induced interfacial energy mainly contributes to the increase in undercooling. The change in undercooling in the magnetic field is calculated theoretically, which is in comparison with experimental data. Additionally, the inhibition of atom diffusion in the magnetic field plays a role in the change of undercooling.     

Efficacy of neurostimulation to treat symptoms of Mal de Debarquement Syndrome. A preliminary study using repetitive transcranial magnetic stimulation

Mal de debarquement syndrome (MdDS) is a rare and poorly understood condition of perceived continual motion. Using a multiple‐case design (n = 13; 8 f; 63.5 ± 12.6 years), this study investigated the efficacy of eight 20‐min sessions, over 4 weeks, of repetitive transcranial magnetic stimulation (rTMS) of the dorsolateral pre‐frontal cortex. Compared to sham, rTMS demonstrated improvement in balance and confidence in daily living activities. rTMS shows promise for the treatment of MdDS. However, larger trials with longer intervention periods are required.     

品牌消费旅程中消费者的认知心理过程——神经营销学视角

品牌消费旅程通常指的是对于品牌消费服务的多维度(包括认知, 情绪, 感觉, 行为和品牌关系)响应。揭示品牌消费旅程的认知心理过程是目前营销学领域之中研究的重点与热点。在梳理当前神经营销领域内有关功能性核磁共振(fMRI)、事件相关电位(ERP)、事件相关震荡(ERO)的相关研究成果后, 将消费者在品牌消费旅程之中的认知心理进程划分为注意吸引、决策形成、消费体验和品牌忠诚四个阶段, 并系统阐述了每个阶段之中消费者心理进程的神经机制与脑区活动, 进而全面立体地揭示消费心理的全貌。未来研究可以进一步探索不同神经指标在具体营销情境下的表征意义, 并结合超扫描技术进一步解析多个被试间的神经耦合情况。     

大脑电刺激在听觉语言加工研究中的应用

大脑电刺激是历史悠久但近年来才广泛应用在人类被试上的实验技术。通过对颅内刺激位点进行电刺激, 并分析引发的暂时性行为功能变化和记录位点的电位活动, 大脑电刺激技术可以揭示认知加工过程中脑区内的功能作用与脑区间的有效连接。通过对听觉语言加工过程相关的丘脑、听觉皮层、高级语言皮层进行电刺激, 现有研究发现了各个脑区的不同功能特点以及不同脑区间的信息传递机制, 为进一步探索听觉语言加工的神经机制提供了新的视角。     

Kinetic study of hydrogen-induced direct phase transformation in Y2Fe17 magnetic alloy on the basis of Kolmogorov’s model

The kinetics of the hydrogen induced direct phase transformation in Y₂Fe₁₇ magnetic alloy has been analysed within the framework of Kolmogorov’s kinetic model. It is established that the transformation can be classified as a diffusion-controlled transformation, which occurs by a mechanism of nucleation and growth with a decreasing nucleation rate of new phases, namely α-Fe and YH₂. A kinetic equation has been obtained that well describes the isothermal kinetic curves of the phase transformation in Y₂Fe₁₇ as a function of the transformation temperature.     

不同频率经颅交流电刺激在精神疾病中的应用

近年来, 研究者开始将经颅交流电刺激技术应用于精神疾病领域中, 其中, 以γ、α频率最受关注。tACS作用于精神疾病的可能机制包括两个方面, 直接调节异常的大脑神经活动和间接改善患者的认知功能。首先, 使用特定频率的tACS作用目标脑区, 可以调节对应频率的神经振荡和大脑功能连接, 通过作用于疾病相关的异常大脑活动, 直接改善患者的临床症状。其次, 并不针对某种疾病特异受损的大脑活动, 而是用tACS激活与认知功能相关的大脑环路, 广泛地提高患者的注意、记忆等多种认知功能, 进而整体上缓解不良症状。目前, 使用tACS治疗精神疾病这一领域还有一些尚未解决、值得探讨的问题。tACS的作用机制研究、刺激参数和范式改进、技术升级, 可以成为心理学、脑科学以及临床医学的重点研究方向。     

The contribution of functional near-infrared spectroscopy (fNIRS) to the presurgical assessment of language function in children

Before performing neurosurgery, an exhaustive presurgical assessment is required, usually including an investigation of language cerebral lateralization. Among the available procedures, the intracarotid amobarbital test (IAT) was formerly the most widely used. However, this procedure has many limitations: it is invasive and potentially traumatic, especially for children. To overcome these limitations, neuroimaging techniques such as functional magnetic resonance imaging (fMRI) have been used. Again, these methods are difficult to use with children, who must remain motionless during data acquisition. Functional near-infrared spectroscopy (fNIRS) is a noninvasive functional imaging technique that is easily applied to pediatric and cognitively limited patients. It has been used recently in epileptic children for presurgical assessment of expressive and receptive language brain lateralization. The aim of this review is to present the contribution of fNIRS to the presurgical assessment of language function in children with neurological diseases.     

A key role for experimental task performance: effects of math talent, gender and performance on the neural correlates of mental rotation

The neurophysiological mechanisms underlying superior cognitive performance are a research area of high interest. The majority of studies on the brain-performance relationship assessed the effects of capability-related group factors (e.g. talent, gender) on task-related brain activations while only few studies examined the effect of the inherent experimental task performance factor. In this functional MRI study, we combined both approaches and simultaneously assessed the effects of three relatively independent factors on the neurofunctional correlates of mental rotation in same-aged adolescents: math talent (gifted/controls: 17/17), gender (male/female: 16/18) and experimental task performance (median split on accuracy; high/low: 17/17). Better experimental task performance of mathematically gifted vs. control subjects and male vs. female subjects validated the selected paradigm. Activation of the inferior parietal lobule (IPL) was identified as a common effect of mathematical giftedness, gender and experimental task performance. However, multiple linear regression analyses (stepwise) indicated experimental task performance as the only predictor of parietal activations. In conclusion, increased activation of the IPL represents a positive neural correlate of mental rotation performance, irrespective of but consistent with the obtained neurocognitive and behavioral effects of math talent and gender. As experimental performance may strongly affect task-related activations this factor needs to be considered in capability-related group comparison studies on the brain-performance relationship.     

Reducing self‐control depletion effects through enhanced sensitivity to implementation: Evidence from fMRI and behavioral studies

Research suggests self-control relies on a limited set of resources that can be diminished by use. Recent theories posit that there are two stages of self-control: recognizing the need for control and implementing controlled responses. We conducted a functional magnetic resonance imaging experiment and an intervention experiment to investigate whether one or both stages were affected by the prior exercise of self-control. Results from both experiments indicated that only the implementation stage was affected. Further, we demonstrate that self-control can be increased by an intervention designed to boost implementation, as opposed to the recognition of the need to control one's responses.