经颅直流电刺激在抑郁症治疗中的应用

已有的神经影像学研究成果揭示, 抑郁症发作的重要原因之一是大脑前额叶皮层结构和功能受损。经颅直流电刺激(tDCS)作为一种无创脑刺激, 选取前额叶皮层作为刺激区域, 通过调节皮层兴奋性来治疗抑郁症, 能够有效缓解抑郁症状和改善受损的认知功能, 疗效明显且持久稳定。针对tDCS在抑郁症治疗研究中的问题, 未来可从有效性、个体差异以及预防干预等六个方面进一步研究, 以期tDCS作为一种具有潜力的治疗手段, 在临床上有更为广泛地应用。     

Frontal cortex functioning in the infant broader autism phenotype

Atypical attention has been proposed as a marker of the broader autism phenotype. In the present study we investigated this and the related process of inhibitory control at the youngest possible age through the study of infant siblings of children with an autism spectrum disorder (Sibs-ASD). Both attention and inhibition have been related to the frontal cortex of the brain. Nine- to ten-month-old Sibs-ASD and low-risk control infants completed the Freeze-Frame task, in which infants are encouraged to inhibit looks to peripherally presented distractors whilst looking at a central animation. The attractiveness of the central stimulus is varied in order to investigate the selectivity of infants’ responses. In line with previous studies, it was found that a subset of Sibs-ASD infants had difficulty disengaging attention from a central stimulus in order to orient to a peripheral stimulus. The Sibs-ASD group also showed less Selective Inhibition than controls. However, Sibs-ASD infants did demonstrate Selective Inhibitory Learning. These results provide preliminary evidence for atypical frontal cortex functioning in the infant broader autism phenotype.     

Developmental changes in dopamine neurotransmission in adolescence: Behavioral implications and issues in assessment

Adolescence is characterized by increased risk-taking, novelty-seeking, and locomotor activity, all of which suggest a heightened appetitive drive. The neurotransmitter dopamine is typically associated with behavioral activation and heightened forms of appetitive behavior in mammalian species, and this pattern of activation has been described in terms of a neurobehavioral system that underlies incentive-motivated behavior. Adolescence may be a time of elevated activity within this system. This review provides a summary of changes within cortical and subcortical dopaminergic systems that may account for changes in cognition and affect that characterize adolescent behavior. Because there is a dearth of information regarding neurochemical changes in human adolescents, models for assessing links between neurochemical activity and behavior in human adolescents will be described using molecular genetic techniques. Furthermore, we will suggest how these techniques can be combined with other methods such as pharmacology to measure the impact of dopamine activity on behavior and how this relation changes through the lifespan.     

Syntactic reconstruction and reanalysis,semantic dead ends,and prefrontal cortex

The left inferior frontal gyrus (LIFG) is crucially has been found to be involved in syntactic processing of various kinds. This study investigates the cortical effects of two types of syntactic processes: (i) Reconstruction in ellipsis (recovery of left-out material given by context, More people have been to Paris than […] to Oslo), using pseudo-elliptical structures (‘dead ends’) as control (More people have been to Paris than I have). (ii) Reanalysis in the face of structural ambiguity in syntactic ‘garden paths’, where the parser initially assigns an incorrect structure and is forced to reanalyze. Reanalysis and reconstruction require additional syntactic processing and were predicted to increase activation in areas otherwise involved in structural computation: LIFG (BA 44, 45), premotor BA 6, and posterior temporal BA 21, 22. This was borne out. The results showed an interaction effect of the types of construction in all three areas reflecting syntactic processing.     

语义启动效应的脑机制研究综述

文章主要介绍了语义启动的过程及其脑机制的研究进展。启动效应是内隐记忆的研究焦点,而语义启动是通过刺激的语义特征来研究启动效应的。语义启动的脑机制研究一般是通过脑损伤、脑成像和ERPs等方法实现的。研究表明,大脑的广泛区域都参与着语义启动过程,尤其是脑前区和大脑的左半球。     

早期听觉剥夺后的大脑可塑性：来自先天性听力障碍群体的证据

皮层功能的正常发展依赖于充分的外部感觉信息的输入。先天性听力障碍群体由于经历早期听觉剥夺, 皮层功能往往出现异常。具体表现为初级听皮层功能退化, 初级、次级听皮层的功能连接变弱, 次级听皮层出现跨通道功能重组; 在后天听力重建后听皮层功能重组仍然存在, 言语加工需要更多高级认知资源的补偿。已有研究在探讨听力重建后皮层的长期可塑性机制、复杂声学环境下言语加工机制、汉语言加工独特性等方面尚不深入, 值得进一步研究。     

语言理解中语义整合的神经机制

语义整合是语言阅读理解中非常重要的环节。随着认知神经科学技术的广泛应用,当前关于语义整合的研究取得了长足进步,各种模型层出不穷。但是不同模型对于语义整合的功能定位及其内在机制却存在较大的争议。本文首先介绍当前关于语义整合的主要模型,然后对当前不同理论模型之间关于语义整合的界定,以及语义整合的功能定位是在额下回还是颞叶的争论进行了分析。我们认为,关于语义整合的实质、语义整合的功能网络将是未来研究的主要方向,相关的研究对于语言理解理论的发展将具有重要的启示。     

SIMPLIFYING HEURISTICS VERSUS CAREFUL THINKING: SCIENTIFIC ANALYSIS OF MILLENNIAL SPIRITUAL ISSUES

There is ample evidence that humans (and other primates) possess a knowledge instinct—a biologically driven impulse to make coherent sense of the world at the highest level possible. Yet behavioral decision‐making data suggest a contrary biological drive to minimize cognitive effort by solving problems using simplifying heuristics. Individuals differ, and the same person varies over time, in the strength of the knowledge instinct. Neuroimaging studies suggest which brain regions might mediate the balance between knowledge expansion and heuristic simplification. One region implicated in primary emotional experience is more activated in individuals who use primitive heuristics, whereas two areas of the cortex are more activated in individuals with a strong knowledge drive: one region implicated in detecting risk or conflict and another implicated in generating creative ideas. Knowledge maximization and effort minimization are both evolutionary adaptations, and both are valuable in different contexts. Effort minimization helps us make minor and routine decisions efficiently, whereas knowledge maximization connects us to the beautiful, to the sublime, and to our highest aspirations. We relate the opposition between the knowledge instinct and heuristics to the biblical story of the fall, and argue that the causal scientific worldview is mathematically equivalent to teleological arguments from final causes. Elements of a scientific program are formulated to address unresolved issues.