Neuro-cognitive mechanisms of decision making in joint action: a human-robot interaction study

In this paper we present a model for action preparation and decision making in cooperative tasks that is inspired by recent experimental findings about the neuro-cognitive mechanisms supporting joint action in humans. It implements the coordination of actions and goals among the partners as a dynamic process that integrates contextual cues, shared task knowledge and predicted outcome of others’ motor behavior. The control architecture is formalized by a system of coupled dynamic neural fields representing a distributed network of local but connected neural populations. Different pools of neurons encode task-relevant information about action means, task goals and context in the form of self-sustained activation patterns. These patterns are triggered by input from connected populations and evolve continuously in time under the influence of recurrent interactions. The dynamic model of joint action is evaluated in a task in which a robot and a human jointly construct a toy object. We show that the highly context sensitive mapping from action observation onto appropriate complementary actions allows coping with dynamically changing joint action situations.     

Do proposed facial expressions of contempt, shame, embarrassment, and compassion communicate the predicted emotion?

Shame, embarrassment, compassion, and contempt have been considered candidates for the status of basic emotions on the grounds that each has a recognisable facial expression. In two studies (N=88, N=60) on recognition of these four facial expressions, observers showed moderate agreement on the predicted emotion when assessed with forced choice (58%; 42%), but low agreement when assessed with free labelling (18%; 16%). Thus, even though some observers endorsed the predicted emotion when it was presented in a list, over 80% spontaneously interpreted these faces in a way other than the predicted emotion.     

Acoustic correlates of emotional dimensions in laughter: arousal, dominance, and valence

Although laughter plays an essential part in emotional vocal communication, little is known about the acoustical correlates that encode different emotional dimensions. In this study we examined the acoustical structure of laughter sounds differing along four emotional dimensions: arousal, dominance, sender's valence, and receiver-directed valence. Correlation of 43 acoustic parameters with individual emotional dimensions revealed that each emotional dimension was associated with a number of vocal cues. Common patterns of cues were found with emotional expression in speech, supporting the hypothesis of a common underlying mechanism for the vocal expression of emotions.     

Motor execution affects action prediction

Previous studies provided evidence of the claim that the prediction of occluded action involves real-time simulation. We report two experiments that aimed to study how real-time simulation is affected by simultaneous action execution under conditions of full, partial or no overlap between observed and executed actions. This overlap was analysed by comparing the body sides and the movement kinematics involved in the observed and the executed action. While performing actions, participants observed point-light (PL) actions that were interrupted by an occluder, followed by a test pose. The task was to judge whether the test pose depicted a continuation of the occluded action in the same depth angle. Using a paradigm proposed by Graf et al., we independently manipulated the duration of the occluder and the temporal advance of the test pose relative to occlusion onset (occluder time and pose time, respectively). This paradigm allows the assessment of real-time simulation, based on prediction performance across different occluder time/pose time combinations (i.e., improved task performance with decreasing time distance between occluder time and pose time is taken to reflect real-time simulation). The PL actor could be perceived as from the front or back, as indicated by task instructions. In Experiment 1 (front view instructions), evidence of action simulation was obtained for partial overlap (i.e., observed and performed action corresponded either in body side or movement kinematics), but not for full or no overlap conditions. The same pattern was obtained in Experiment 2 (back view instructions), ruling out a spatial compatibility explanation for the real-time pattern observed. Our results suggest that motor processes affect action prediction and real-time simulation. The strength of their impact varies as a function of the overlap between observed and executed actions.     

Does a sensory processing deficit explain counting accuracy on rapid visual sequencing tasks in adults with and without dyslexia?

The experiments conducted aimed to investigate whether reduced accuracy when counting stimuli presented in rapid temporal sequence in adults with dyslexia could be explained by a sensory processing deficit, a general slowing in processing speed or difficulties shifting attention between stimuli. To achieve these aims, the influence of the inter-stimulus interval (ISI), stimulus duration, and sequence length were evaluated in two experiments. In the first that used skilled readers only, significantly more errors were found with presentation of long sequences when the ISI or stimulus durations were short. Experiment 2 used a wider range of ISIs and stimulus durations. Compared to skilled readers, a group with dyslexia had reduced accuracy on two-stimulus sequences when the ISI was short, but not when the ISI was long. Although reduced accuracy was found on all short and long sequences by the group with dyslexia, when performance on two-stimulus sequences was used as an index of sensory processing efficiency and controlled, group differences were found with presentation of stimuli of short duration only. We concluded that continuous, repetitive stimulation to the same visual area can produce a capacity limitation on rapid counting tasks in all readers when the ISIs or stimulus durations are short. While reduced accuracy on rapid sequential counting tasks can be explained by a sensory processing deficit when the stimulus duration is long, slower processing speed in the group with dyslexia explains the greater inaccuracy found as sequence length is increased when the stimulus duration is short.     

统计学习与双语认知的关系

统计学习是提取环境输入潜在规则的一种认知机制,其与语言的关联已得到证实。双语认知是学界关注的热点之一。统计学习与双语认知的关系如何?文章先介绍统计学习认知机制及其与语言的关系,然后从“统计学习能力可否预测二语学习表现”、“统计学习训练能否促进二语学习”和“双语经验能否提高统计学习能力”三个维度述评相关文献,并指出未来可从输入特征、个体差异和神经科学角度进一步探讨统计学习与双语认知的关系。     

马克思主义的人道主义

我们可以毫不犹豫地说,我们的时代是各种人道主义相互对垒的时代。打着人道主义招牌的派别不仅多如牛毛,而且竞争激烈,甚至相互论战。在我们的时代,由于个人的生活问题占着日益重要的地位,政治斗争往往表现为指责对方不讲人道主义或者反对人道主义。但这种指责丝毫不能证明自己是真正的人道主义者,也不能避免自己被别人指责为不讲人道主义。人道主义之所以大受欢迎以及它的种种派别之争无非说明了以下的事实:今天,人的生活遭受到空前的威胁,因此人至少需要听到一些安慰的话语,听到一些祈求人类幸福的话语。因此,谈到人和人的幸福(尤其在宣传中),任     

整块并行分布处理与认知科学的计算主义基础

60年代后期,心灵哲学家(或译心智哲学家)之间曾有一场大争论,关涉哥德尔定理的不可判定命题是否为下述结论提供了很好的理由的问题:人脑在计算上天生地强于任何从原则上说可以构造出来的机械的(即非人类的)计算自动机。应予注意的是:这场争论产生于这样的时刻,当时人们公认计算自动机的具体例证是冯·诺意曼型的串行的,顺序操作的数字计算机。如今,W.D.希利斯(Hillis)已经发明一种具有完全相异结构的计算自动机,即所谓的“连接机”