面部表情的类别知觉及其个体差异

面部表情类别知觉效应是指连续变化的表情在人脑中按照类别表征, 且不同类别的表情之间存在明显的类别界线。介绍了面部表情类别知觉效应的行为和脑电研究范式及基础研究, 综述了攻击性、抑郁症、精神分裂症、社交焦虑等对面部表情类别知觉的影响, 以及面部表情类别知觉的发展研究。综述表明, 类别知觉研究能够揭示不同人群表情知觉类别界线及其偏移情况, 有助于解释相应的社会行为。未来研究应注重对面部表情类别知觉效应的个体差异和神经生理机制的探索。     

Modeling the categorical perception of speech sounds: A step toward biological plausibility

Our native language has a lifelong effect on how we perceive speech sounds. Behaviorally, this is manifested as categorical perception, but the neural mechanisms underlying this phenomenon are still unknown. Here, we constructed a computational model of categorical perception, following principles consistent with infant speech learning. A self-organizing network was exposed to a statistical distribution of speech input presented as neural activity patterns of the auditory periphery, resembling the way sound arrives to the human brain. In the resulting neural map, categorical perception emerges from most single neurons of the model being maximally activated by prototypical speech sounds, while the largest variability in activity is produced at category boundaries. Consequently, regions in the vicinity of prototypes become perceptually compressed, and regions at category boundaries become expanded. Thus, the present study offers a unifying framework for explaining the neural basis of the warping of perceptual space associated with categorical perception.     

偏侧化颜色范畴知觉不依赖于语言?

本研究探讨了偏左脑颜色范畴知觉依赖于语言还是范畴。三组被试分别完成无干扰、语言加工干扰和范畴加工干扰视觉搜索任务。结果发现：无干扰组、语言加工干扰组和范畴加工干扰组的视觉搜索任务中分别出现了偏左脑颜色范畴知觉、左脑劣势颜色范畴知觉和无偏侧化颜色范畴知觉。此结果表明,偏左脑颜色范畴知觉可能主要是语言范畴作为一种范畴对颜色知觉的影响效应,但语言范畴的语言属性也会对颜色知觉产生影响。     

Central visual persistences: I. Visual and kinesthetic interactions

Phenomena associated with 'central visual persistences' (CPs) are new to both medical and psychological literature. Five subjects have reported similar CPs: positive afterimages following brief fixation of high-contrast objects or drawings and eye closure. CPs duplicate shapes and colors of single objects, lasting for about 15 s. Unlike retinal afterimages, CPs do not move with the eyes but are stable in extrapersonal space during head or body rotations. CPs may reflect sustained neural activity in neurons of association cortex, which mediate object perception. A remarkable finding is that CPs can be moved in any direction by the (unseen) hand holding the original seen object. Moreover, a CP once formed will 'jump' into an extended hand and 'stick' in that hand as it moves about. The apparent size of a CP of a single object is determined by the size of the gap between finger and thumb, even when no object is touched. These CPs can be either magnified or minified via the grip of the extended hand. The felt orientation of the hand-held object will also determine the orientation of the CP seen in that hand. Thus, kinesthetic signals from hand and arm movements can determine perceived location, size, and orientation of CPs. A neural model based on physiological studies of premotor, temporal, parietal, and prefrontal cortices is proposed to account for these novel phenomena.     

Categorical perception of morphed objects using a free-naming experiment

Morphed figures entail a dominant and nondominant interpretation. Testing perception of morphed objects using forced-choice methods demonstrates that morphed figures are perceived as their dominant interpretation (“categorical perception”, or CP). Using a more natural free-naming response could reveal whether CP is an effect independent of method. In Experiment 1, therefore, series of morphed figures were tested for CP using free naming. Half of the morph series were identified as CP patterns. In Experiment 2, we used forced choice to investigate CP, resulting in an increase of number of CP series compared to free naming. The overlap between CP series of Experiments 1 and 2 was small, however. Experiment 3 revealed that higher perceptual similarity between the extremes of the series was strongly related to CP for the free-naming method, in contrast to the forced-choice method. We conclude that the observation of CP depends on the intactness of the intrinsic object structure caused by the morphing procedure.     

语言对知觉的影响—— 来自颜色范畴知觉研究的证据

介绍了近年来语言和颜色范畴知觉关系研究的新进展, 特别是颜色范畴知觉效应的偏侧化、婴幼儿颜色范畴知觉的特点等。同时指出了今后需要进一步研究的问题, 如颜色范畴知觉效应偏侧化与语言的关系、右脑语言优势者颜色范畴知觉的特点、颜色加工脑区和语言加工脑区之间的关系以及婴幼儿颜色范畴知觉特点的追踪研究等。     

颜色类别知觉效应的机制：语言的作用

颜色类别知觉效应(Category Perception, CP效应)表明, 在颜色之间物理差异距离相等的前提下, 个体区分不同类别的颜色比区分同一类别的颜色更快、更准确。这一效应产生的机制成为普遍进化理论和Sapir-Whorf假设之间争论的重要证据。支持CP效应由语言驱动的学者提出了CP效应单侧化、受语言即时任务影响、跨语言研究和神经生理机制等证据, 以表明语言在CP效应中起决定性的作用; 支持CP效应具有普遍性的学者以CP效应双侧化、婴儿的CP效应、跨语言的反证等证据提出了质疑。近年来, 出现了第三种观点, 认为在颜色CP效应中语言驱动机制和普遍机制并存, 这种理论是普遍进化理论和Whorf假设的折衷观点。从支持CP效应由语言驱动的证据、支持CP效应独立于语言的证据以及支持两种机制并存的观点等三个方面入手, 可分析颜色CP效应的产生机制及语言在其中所起的作用, 未来研究可从概念系统渗入知觉系统的角度进行拓展。     

汉语语音范畴性知觉及其发展

范畴性是言语知觉的一个显著特征,长期以来一直受到研究者的普遍关注。但汉语不同语音特征的范畴性知觉特点及其发展模式迄今为止还很少有研究涉及。本研究利用语音合成的方法分别改变辅音的送气/不送气特征和声调的基频曲线,生成语音刺激连续体,采用范畴性知觉的经典研究范式探讨了汉语正常成人被试嗓音启动时间（Voice onset time,VOT）和声调范畴性知觉的特点及不同年龄儿童的发展模式。研究结果表明：（1）成人被试对VOT和声调的知觉是范畴性的;（2）对于汉语声调特征,6岁儿童已经具有类似成人的范畴性知觉能力;而在VOT这一维度上,范畴知觉能力随着年龄发展不断精细化,但7岁儿童也尚未达到成年人的敏感程度,说明汉语VOT和声调这两个不同的语音特征经历了不同的发展模式。     

A global workspace model for phenomenal and access consciousness

Both the global workspace theory and Block’s distinction between phenomenal and access consciousness, are central in the current debates about consciousness and the neural correlates of consciousness. In this article, a unifying global workspace model for phenomenal and access consciousness is proposed. In the model, recurrent neural interactions take place in distinct yet interacting access and phenomenal brain loops. The effectiveness of feedback signaling onto sensory cortical maps is emphasized for the neural correlates of phenomenal consciousness. Two forms of top-down attention, attention for perception and attention for access, play differential roles for phenomenal and access consciousness. The model is implemented in a neural network form, with the simulation of single and multiple visual object processing, and of the attentional blink.     

右视野颜色范畴知觉是长期习得语言范畴还是即时分类颜色的结果?

本研究探讨了右视野颜色范畴知觉是由长期习得语言范畴还是即时分类颜色引起的。实验1让被试先将深绿、浅绿、浅蓝和深蓝四种颜色分为四种范畴,再接受视觉搜索任务。结果发现,视觉搜索任务中出现了与颜色分类相应的右视野颜色范畴知觉,且这一效应在任务的早段就表现出来,提示右视野颜色范畴知觉并非由分类颜色所引起。实验2让被试将四种渐进的蓝色分为两种范畴,并在之前与后接受视觉搜索任务。结果表明,分类后的视觉搜索中并未出现右视野颜色范畴知觉。先前研究表明,习得语言范畴使四种颜色为两种范畴后,颜色辨别会出现右视野范畴效应。因此,这一结果提示右视野颜色范畴知觉并非由分类颜色,而是由习得语言范畴所引起的。总体上,本研究提示右视野颜色范畴知觉是由长期习得语言范畴,而非即时分类颜色引起的,进一步揭示了语言与颜色知觉的关系。     

Symmetry perception in humans and macaques

The human ability to detect symmetry has been a topic of interest to psychologists and philosophers since the 19th century, yet surprisingly little is known about the neural basis of symmetry perception. In a recent fMRI study, Sasaki and colleagues begin to remedy this situation. By identifying the neural structures that respond to symmetry in both humans and macaques, the authors lay the groundwork for understanding the neural mechanisms underlying symmetry perception.     

An oscillatory correlation model of visual motion analysis

We describe and evaluate a model of motion perception based on the integration of information from two parallel pathways: a motion pathway and a luminance pathway. The motion pathway has two stages. The first stage measures and pools local motion across the input animation sequence and assigns reliability indices to these pooled measurements. The second stage groups locations on the basis of these measurements. In the luminance pathway, the input scene is segmented into regions on the basis of similarities in luminance. In a subsequent integration stage, motion and luminance segments are combined to obtain the final estimates of object motion. The neural network architecture we employ is based on LEGION (locally excitatory globally inhibitory oscillator networks), a scheme for feature binding and region labeling based on oscillatory correlation. Many aspects of the model are implemented at the neural network level, whereas others are implemented at a more abstract level. We apply this model to the computation of moving, uniformly illuminated, two-dimensional surfaces that are either opaque or transparent. Model performance replicates a number of distinctive features of human motion perception.     

Thresholds for color discrimination in English and Korean speakers

Categorical perception (CP) is said to occur when a continuum of equally spaced physical changes is perceived as unequally spaced as a function of category membership (Harnad, S. (Ed.) (1987). Psychophysical and cognitive aspects of categorical perception: A critical overview. Cambridge: Cambridge University Press). A common suggestion is that CP for color arises because perception is qualitatively distorted when we learn to categorize a dimension. Contrary to this view, we here report that English speakers show no evidence of lowered discrimination thresholds at the boundaries between blue and green categories even though CP is found at these boundaries in a supra-threshold task. Furthermore, there is no evidence of different discrimination thresholds between individuals from two language groups (English and Korean) who use different color terminology in the blue-green region and have different supra-threshold boundaries. Our participants’ just noticeable difference (JND) thresholds suggest that they retain a smooth continuum of perceptual space that is not warped by stretching at category boundaries or by within-category compression. At least for the domain of color, categorical perception appears to be a categorical, but not a perceptual phenomenon.     

The effect of Stroop interference on the categorical perception of color

In two experiments, we examined the effects of Stroop interference on the categorical perception (CP; better cross-category than within-category discrimination) of color. Using a successive two-alternative forced choice recognition paradigm (deciding which of two stimuli was identical to a previously presented target), which combined to-be-remembered colors with congruent and incongruent Stroop words, we found that congruent color words facilitated CP, whereas incongruent color words reduced CP. However, this was the case only when Stroop interference was presented together with the target color, but not when Stroop stimuli were introduced at the test stage. This suggests that target name, but not test name generation, affects CP. Target name generation may be important for CP because it acts as a category prime, which, in turn, facilitates cross-category discrimination.     

汉语元音对声调感知边界的影响

本项研究基于现代汉语普通话声调感知具有范畴性这一结论(Wang, 1976), 以普通话中6个单元音(/a//?//F//i//u//y/, 即拼音a、o、e、i、u、ü)阴平(T1)到阳平(T2)调的连续统(continuum)为实验语料, 用专业语音学软件Praat合成连续统语音样本, 对20名平均年龄为22.90岁的普通话母语者进行声调感知实验, 即让被试对所听刺激进行T1或T2的二选一鉴别测试(identification test), 从而探究单元音的内在音高(intrinsic pitch)与声调感知边界(boundary)的关系。本文借鉴Wang (1976)和Peng等(2010)对元音/i/声调连续统的合成方法, 使声调感知研究拓展到普通话中除/i/之外的其他5个单元音, 对以上两项研究起到一定的对照作用。研究发现, 元音会对T1到T2的声调范畴感知边界位置产生影响, 低元音/a/的内在音高较低, 其边界位置亦始终低于其他元音, 且具有显著性差异, 实验结果证明, 内在音高会对感知边界产生影响, 从而支持了Ohala和Eukel (1976)的“舌位拉伸”假说。     

On feeling in control: a biological theory for individual differences in control perception

This review aims to create a cross-disciplinary framework for understanding the perception of control. Although, the personality trait locus of control, the most common measure of control perception, has traditionally been regarded as a product of social learning, it may have biological antecedents as well. It is suggested that control perception follows from the brain's capacity for self regulation, leading to flexible and goal directed behaviours. To this account, a model is presented which spans several levels of analyses. On a behavioural level, control perception may be a corollary of emotion regulation, executive functions, and social cognition. On a neural level, these self-regulatory functions are substantiated in part by the dorsolateral and ventral prefrontal cortex and the anterior cingulate cortex. In addition, a possible role of subcortical-cortical dopamine pathways underlying control perception is discussed.     

Categorical perception occurs in newly learned faces, other-race faces, and inverted faces

On the basis of findings that categorical perception (CP) is possible in complex visual stimuli such as faces, the present study tested for CP on continua between unfamiliar face pairs. Results indicate that CP can be observed for unfamiliar faces, in both familiar (same-race) and unfamiliar (other-race) groups. In addition, significant CP effects were observed in inverted faces. Finally, half-continua were tested where midpoint stimuli became endpoints. This was done to ensure that stimulus artifacts did not account for the observed CP effects. Consistent with the perceptual rescaling associated with CP, half-continua showed a rescaled CP effect. We argue that these CP effects are based on the rapid acquisition of perceptual equivalence classes.