Psychophysics of Kinesthesis

A horizontal straight-arm movement was used to determine the relationship between the physical stimulus continuum and the psychological continuum of kinesthetic extent of arm movement. A power function with an exponent of 1.075 best described this relationship. In addition, to classify extent of movement as belonging to either a prothetic or metathetic continuum, the category scale was derived. According to the functional criteria described by Stevens (1957), extent of movement was subserved by a metathetic process which would indicate that, for the present task, judgments were made through the use of positional cues rather than amplitude cues.     

The structure of “communities” and communications in the new millennium

The three lineages of information,—the genetic, the cultural and artifactual—will increasingly merge their constituent information contents through advances in biotechnology and information technology. This will redefine what constitutes “social” and what constitutes “community.” A community's members communicate with their “significant others” and change their internal information states (and their internal and external behaviors). Under conditions of merging, information exchanges occur across all the three lineages. In this sense, the concept of significant other,—that is, a communicating entity—, is now spread from human communities to encompass also the biological and the artifactual. A seamless merging between the three realms now occurs affecting their respective internal information stores. The resulting image of interactions that now arises is of multiple oceans of communities, operating at different levels, the genetic, the cultural and the artifactual. There are exchanges across the different levels, up and down and sideways, as information is translated from one realm to the other. These dynamics result in changes in the evolutionary characteristics of each lineage and sub‐lineage, including the internal perceptions from within a lineage, namely in the language of evolutionary epistemology, its “meanings” and “hypotheses” on the world. A future sociology must necessarily take into account these factors and incorporate the dynamics of all three realms.     

Impact of negative affectively charged stimuli and response style on cognitive-control-related neural activation: An ERP study

The canonical AX-CPT task measures two forms of cognitive control: sustained goal-oriented control (“proactive” control) and transient changes in cognitive control following unexpected events (“reactive” control). We modified this task by adding negative and neutral International Affective Picture System (IAPS) pictures to assess the effects of negative emotion on these two forms of cognitive control. Proactive and reactive control styles were assessed based on measures of behavior and electrophysiology, including the N2 event-related potential component and source space activation (Low Resolution Tomography [LORETA]). We found slower reaction-times and greater DLPFC activation for negative relative to neutral stimuli. Additionally, we found that a proactive style of responding was related to less prefrontal activation (interpreted to reflect increased efficiency of processing) during actively maintained previously cued information and that a reactive style of responding was related to less prefrontal activation (interpreted to reflect increased efficiency of processing) during just-in-time environmentally triggered information. This pattern of results was evident in relatively neutral contexts, but in the face of negative emotion, these associations were not found, suggesting potential response style-by-emotion interaction effects on prefrontal neural activation.     

Birth of an Abstraction: A Dynamical Systems Account of the Discovery of an Elsewhere Principle in a Category Learning Task

Human participants and recurrent (“connectionist”) neural networks were both trained on a categorization system abstractly similar to natural language systems involving irregular (“strong”) classes and a default class. Both the humans and the networks exhibited staged learning and a generalization pattern reminiscent of the Elsewhere Condition (Kiparsky, 1973). Previous connectionist accounts of related phenomena have often been vague about the nature of the networks’ encoding systems. We analyzed our network using dynamical systems theory, revealing topological and geometric properties that can be directly compared with the mechanisms of non‐connectionist, rule‐based accounts. The results reveal that the networks “contain” structures related to mechanisms posited by rule‐based models, partly vindicating the insights of these models. On the other hand, they support the one mechanism (OM), as opposed to the more than one mechanism (MOM), view of symbolic abstraction by showing how the appearance of MOM behavior can arise emergently from one underlying set of principles. The key new contribution of this study is to show that dynamical systems theory can allow us to explicitly characterize the relationship between the two perspectives in implemented models.     

Pathways to flourishing among pharmacy students: The role of study demands and lecturer support

This study investigated possible pathways to flourishing among pharmacy students attending a South African university (N = 799; females = 81.6%; Afrikaans-speakers = 84.7%, mean age = 20.42 years, SD = 2.25 years). The students completed the Mental Health Continuum – Short Form (MHC-SF) and an Overload and Lecturer Support Survey. Of the 779 pharmacy students, 40.3% self-reported as flourishing, with high mean scores on workload and lecturer support. The level of emotional well-being of year group 2 was the highest. Following structural equation modelling, overload and lecturer support explained between 18% and 31% of the variance in the flourishing of the different year groups. From the second to the third year, the predictive value of overload and lecturer support for flourishing decreased by 8.8%. Lecturer support and low overload appear to play a positive role in the flourishing of higher education students.     

视觉词汇加工的动态神经网络及其形成

揭示大脑加工的神经网络机制成为认知神经科学研究的最新取向.本研究以视觉词汇加工脑区(VWFA)的神经功能作为切入点,探讨视觉词汇加工神经网络的动态机制及其形成.研究一考察VWFA在刺激驱动和任务调节下的动态激活,及其与语音、语义脑区所组成神经网络的动态机制.研究二通过跨文化对比以及儿童阅读发展研究,阐明语言经验对视觉词汇加工网络的塑造作用.研究三对比功能网络、静息网络以及白质纤维束联结,探讨视觉词汇加工网络的动态联结及其形成.研究结果有助于建构视觉词汇加工的神经生理模型,为基于脑科学的阅读教学和阅读障碍矫治奠定理论基础,为认知神经科学研究提供了新的思路.     

伤害回避的脑机制及其生物基础

伤害回避是指个体对厌恶刺激信号做出强烈的反应,并学会被动地回避惩罚的一种倾向,这一倾向使得个体反复思考未来的结局,并谨慎小心地对待不确定情景中的事件,进而更有可能诱发情感障碍。伤害回避涉及的神经网络包括三个子网络,即额顶叶-前扣带皮层的连接、皮层-杏仁核的连接和白质通道的结构性连接,这三个子网络分别与羞怯感-易疲劳性、预期担心以及不确定环境中的害怕情绪有关。而其生物基础则包括单一基因多态性和基因多态间的交互作用。今后的研究应该集中在深化伤害回避神经网络与生物基础间的联合机制、研究三种及以上基因多态间的交互作用、考察其他因素对基因效应的调节作用、注重伤害回避四种亚型相关神经网络之间的连接、探讨5-HT4等其他几种5-羟色胺受体多态性与伤害回避的关系以及分析伤害回避内部机制在抗抑郁治疗中的作用等方面。     

Artificial intelligence for the measurement of vocal stereotypy

Both researchers and practitioners often rely on direct observation to measure and monitor behavior. When these behaviors are too complex or numerous to be measured in vivo, relying on direct observation using human observers increases the amount of resources required to conduct research and to monitor the effects of interventions in practice. To address this issue, we conducted a proof of concept examining whether artificial intelligence could measure vocal stereotypy in individuals with autism. More specifically, we used an artificial neural network with over 1,500 minutes of audio data from 8 different individuals to train and test models to measure vocal stereotypy. Our results showed that the artificial neural network performed adequately (i.e., session-by-session correlation near or above .80 with a human observer) in measuring engagement in vocal stereotypy for 6 of 8 participants. Additional research is needed to further improve the generalizability of the approach.     

言语想象的神经机制

言语想象不仅在大脑预处理机制方面起到重要的作用,还是目前脑机接口领域研究的热点。与正常言语产生过程相比,言语想象的理论模型、激活脑区、神经传导路径等均与其有较多相似之处。而言语障碍群体的言语想象、想象有意义的词语和句子时的脑神经机制与正常言语产生存在差异。鉴于人类言语系统的复杂性,言语想象的神经机制研究还面临一系列挑战,未来研究可在言语想象质量评价工具及神经解码范式、脑控制回路、激活通路、言语障碍群体的言语想象机制、词语和句子想象的脑神经信号等方面进一步探索,为有效提高脑机接口的识别率提供依据,为言语障碍群体的沟通提供便利。     

增塑剂DEHP的神经和行为发育毒性

增塑剂邻苯二甲酸二乙基己酯(Di-(2-ethylhexyl) phthalate,DEHP)是一种具有拟雌激素和抗雄激素活性的环境内分泌干扰物,人类和野生动物可通过不同途径终生暴露于DEHP.母体摄入的DEHP可通过胎盘和乳汁转入子代体内并进入脑组织.围生期DEHP暴露性别特异性地改变子代大鼠下丘脑视前区芳香酶活性而影响雌激素合成,并通过改变雌激素受体活性干扰雌激素对脑发育的调节作用.DEHP及其代谢产物可以影响神经细胞的增殖分化和突触形成,干扰性激素调控发育过程中的下丘脑氨基酸递质系统对促性腺激素释放激素分泌的刺激作用,影响中脑多巴胺递质系统发育而诱导自发性多动症.DEHP对脑发育的作用最终影响动物的早期行为、学习记忆和情感等行为发育.