Deaf hearing: Implicit discrimination of auditory content in a patient with mixed hearing loss

We describe a patient LS, profoundly deaf in both ears from birth, with underdeveloped superior temporal gyri. Without hearing aids, LS displays no ability to detect sounds below a fixed threshold of 60 dBs, which classifies him as clinically deaf. Under these no-hearing-aid conditions, when presented with a forced-choice paradigm in which he is asked to consciously respond, he is unable to make above-chance judgments about the presence or location of sounds. However, he is able to make above-chance judgments about the content of sounds presented to him under forced-choice conditions. We demonstrated that LS has faint sensations from auditory stimuli, but questionable awareness of auditory content. LS thus has a form of type-2 deaf hearing with respect to auditory content. As in the case of a subject with acquired deafness and deaf hearing reported on a previous occasion, LS’s condition of deaf hearing is akin in some respects to type-2 blindsight. As for the case of type 2 blindsight the case indicates that a form of conscious hearing can arise in the absence of a fully developed auditory cortex.     

自传记忆提取的神经机制及其研究方法

自传记忆（autobiographical memory,AM）是个人生活事件的记忆,它在人类认知中建构起自我、情绪、个人意义及其交互作用的主通道。对自传记忆的研究在广度上极大丰富了记忆的研究内容,并成为记忆研究乃至整个认知心理学新的方法论的增长点。利用PET,fMRI和皮层慢电位等手段对自传记忆进行研究,可以加深对自传记忆神经机制的认识。就Conway等提出的SMS模型中,自传记忆提取的神经解剖分布,自传记忆提取偏侧化问题和海马在自传记忆中的作用进行总结和评述,并分析比较了自传记忆脑机制的研究方法     

Neonatal testosterone augmentation increases juvenile play fighting but does not influence the adult dominance relationships of male rats

Neonatal male rats were either injected subcutaneously with testosterone propionate (TP) or oil vehicle. When weaned, each treated pup was paired with an untreated male sibling. The play fighting of TP-and oil-treated rats were compared at the juvenile phase (30–36 days), and in adulthood (84–90 days). In the juvenile phase, the rate of initiating playful attacks was significantly greater for TP-treated rats. Playful defense in response to such attacks did not differ between TP- and oil-treated rats. At the completion of the study, cortical thickness was measured for all the groups of rats. Oil treatment decreased overall cortical thickness relative to untreated pairmates, whereas TP treatment did not. Both oil and TP treatment abolished the asymmetry in hemispheric thickness, which was present in the untreated pairmates. The reversal of at least one of these injectioninduced changes in the cortex by TP provided independent evidence for the effectiveness of the TP treatment. As adults, neither the TP treatment nor the oil treatment influenced which pairmate became dominant. Dominance was judged by which pairmate initiated less playful attacks. Therefore, it is concluded that the early neonatal testosterone surge is not likely to be a factor in influencing the behaviors that lead to adult dominance. In contrast, play fighting is influenced by hormonal events in this early neonatal phase. It thus appears that play fighting and the aggressive systems subserving dominance relationships are differentially controlled. © 1992 Wiley-Liss, Inc.     

A psychophysiological model of emotion space

Despite a wide variety of emotions that can be subjectively experienced, the emotion space has consistently revealed a low dimensionality. The search for corresponding somato-visceral response patterns has been only moderately successful. The authors suggest a solution based on an assumed parallelism between emotion coding and color coding. According to the color detection model proposed by Sokolov and co-workers, neurons responsible for color detection are triggered by a combination of excitations in a limited number of input cells. Similarly, a limited number of input channels may feed complex emotion detectors being located on a hypersphere in a four-dimensional emotion space, the three angles of which correspond to emotional tone, intensity, and saturation, in parallel to hue, lightness, and saturation in color perception. The existence of such a four-dimensional emotion space in the subjective domain is shown by using schematic facial expressions as stimuli. A neurophysiological model is provided in which reticular, hypothalamic, and limbic structures constitute input channels of an emotion detecting system, thus acting as the first layer of emotion predetectors. Hypothalamic neurons with differential sensitivity for various transmitters may elicit a subsequent selective activation in a second layer of predetectors at the thalamic level. The latter are suggested to trigger emotion detectors located in cortical areas, the action of which should be revealed by measures of central nervous system activity. Preliminary results from evoked potential studies show that switching between schematic faces that express different emotions may be used as an objective measure for establishing a psychophysiological emotion space.     

威胁性信息检测的脑机制

快速而准确地检测威胁性信息是进化过程中形成的一种重要能力,是有效应对危险的前提条件,对有机体的生存具有重要价值.威胁性信息的检测由不同的神经通路合作完成.在视觉通道中,皮层通路的精确检测和皮层下通路的快速检测在杏仁核得到整合.杏仁核能接受多感觉通道的信息输入,并接受额叶的调节,是威胁性信息加工中连通自上而下加工和自下而上加工的枢纽.将来的研究需要进一步关注杏仁核的功能以及不同的神经通路如何合作完成威胁性信息的检测.     

Cognition and lobar morphology in full mutation boys with fragile X syndrome

The aims of the present study are twofold: (1) to examine cortical morphology (CM) associated with alterations in cognition in fragile X syndrome (FXS); (2) to characterize the CM profile of FXS versus FXS with an autism diagnosis (FXS + Aut) as a preliminary attempt to further elucidate the behavioral distinctions between the two sub-groups. We used anatomical magnetic resonance imaging surface-based morphometry in 21 male children (FXS N = 11 and age [2.27-13.3] matched controls [C] N = 10). We found (1) increased whole hemispheric and lobar cortical volume, cortical thickness and cortical complexity bilaterally, yet insignificant changes in hemispheric surface area and gyrification index in FXS compared to C; (2) linear regression analyses revealed significant negative correlations between CM and cognition; (3) significant CM differences between FXS and FXS + Aut associated with their distinctive behavioral phenotypes. These findings are critical in understanding the neuropathophysiology of one of the most common intellectual deficiency syndromes associated with altered cognition as they provide human in vivo information about genetic control of CM and cognition.     

内侧前额叶皮质—— “自我”的神经基础

自我神经基础的探讨常基于自我相关加工的研究, 涉及皮质中线结构各个脑区甚至全脑协同作用。内侧前额叶皮质及其次成分在自我相关加工中发挥重要作用：腹内侧前额叶皮质较多支持默认模式下的自我加工、自我信息的觉察和“在线”自我加工, 背内侧前额叶皮质主要参与有意识的自我参照加工、自我信息的评价和“主导的”自我加工。在自我-他人表征中, 自我-他人表征的情感性、认知性和文化性因素均调节内侧前额叶皮质及次成分的活动。未来在动态的时间和人际背景中解析自我加工的神经机制是重要的研究方向。     

Connecting the Many Levels and Facets of Cognitive Aging

Basic cognitive mechanisms, such as the abilities to briefly maintain, focus, and process information, decline with age. Related fields of cognitive aging research have been advancing rapidly, but mostly independently, at the biological, information processing, and behavioral levels. To facilitate integration, this article reviews research on cognitive aging at the different levels, and describes a recent integrative theory postulating that aging-related deficiencies in neurotransmission cause increased noise in information processing and less distinctive cortical representation, which in turn lead to cognitive deficits. Aging-related attenuation of catecholaminergic modulation can be modeled by lowering a neural network parameter to reduce the signal-to-noise ratio of information processing. The performance of such models is consistent with benchmark phenomena observed in humans, ranging from age differences in learning rate, asymptotic performance, and interference susceptibility to intra- and interindividual variability and ability dedifferentiation. Although the details of the conjectured sequence of effects linking neuromodulation to cognitive aging deficits await further empirical validation, cross-level theorizing of the kind illustrated here could foster the coevolution of related fields through cross-level data synthesis and hypothesis testing.     

努力控制及其神经基础

本文对努力控制的概念、发展及其神经基础进行了归纳和总结。我们发现努力控制涉及的脑区主要包括背外侧和腹外侧前额叶,前扣带回,顶上和顶下小叶以及辅助运动皮层等。此外,通过分析对比后发现努力控制与执行功能之间在行为表现和神经基础上有密切关系：两者都与个体的学业成绩、情绪状态和攻击行为等有关;努力控制涉及的脑区有很大部分处于具有执行功能的突显网络和额顶控制网络。这些证据表明两者之间可能有共同的脑结构基础。