Learning Orthographic Structure With Sequential Generative Neural Networks

Learning the structure of event sequences is a ubiquitous problem in cognition and particularly in language. One possible solution is to learn a probabilistic generative model of sequences that allows making predictions about upcoming events. Though appealing from a neurobiological standpoint, this approach is typically not pursued in connectionist modeling. Here, we investigated a sequential version of the restricted Boltzmann machine (RBM), a stochastic recurrent neural network that extracts high‐order structure from sensory data through unsupervised generative learning and can encode contextual information in the form of internal, distributed representations. We assessed whether this type of network can extract the orthographic structure of English monosyllables by learning a generative model of the letter sequences forming a word training corpus. We show that the network learned an accurate probabilistic model of English graphotactics, which can be used to make predictions about the letter following a given context as well as to autonomously generate high‐quality pseudowords. The model was compared to an extended version of simple recurrent networks, augmented with a stochastic process that allows autonomous generation of sequences, and to non‐connectionist probabilistic models (n‐grams and hidden Markov models). We conclude that sequential RBMs and stochastic simple recurrent networks are promising candidates for modeling cognition in the temporal domain.     

The influence of affective factors on time perception

Several studies have suggested that both affective valence and arousal affect the perception of time. However, in previous experiments, the two affective dimensions have not been systematically controlled. In this study, standardized photographic slides rated for emotional valence and arousal were projected to two groups of subjects for 2, 4, and 6 sec. One group of subjects estimated the projection duration on an analog scale, whereas the second group of subjects reproduced the intervals by pushing a button. Heart rate and skin conductance responses were also recorded during stimulus presentation as indices of attention and arousal. Time estimation results showed neither a main effect of valence nor a main effect of arousal. A highly significant valence × arousal interaction affected duration judgments. For low-arousal stimuli, the duration of negative slides was judged relatively shorter than the duration of positive slides. For high-arousal stimuli, the duration of negative slides was judged longer than the duration of positive slides. The same interaction pattern was observed across judgment modalities. These results are interpreted in terms of a model of action tendency, in which the level of arousal controls two different motivational mechanisms, one emotional and the other attentional.     

Les “règles de la discussion légitime” dans la logique de Port-Royal

In the XVIIth century the conflict which opposed the jansenists to the jesuits involved the problem of the due process in theological matter. The jesuits heralded the thesis that the infallibility of the Church has to be extended from dogmatics (quaestio iuris) to the historical facts (quaestio facti). On the opposite side Arnauld maintained that such an opinion was monstruous: also in religious matters the fact has to be proved according to the principles of a due process, and not by authority. In this article the thesis pleaded by the jansenists is considered in connection with the model of argumentative procedure offered by the Port-Royal logic.The Logique ou Art de penser (1622) by Antoine Arnauld and Pierre Nicole seems to have rediscovered the classical principles of the theory of argumentation: from the burden of proof to the idea of probable truth. But really a new model of adversary-system has been introduced into the modern mind, which is very different in concept from the topical tradition. The basic metaphor of combat, implying that the truth will prevail in the fight, is compatible with the epistemological premises of the modern logic (as the separation between fact and value). Therefore the problem of the fact-finding seems to be attracted into the area of the logic of information, and not of the theory of argumentation.

     

Arithmetic,set theory,reduction and explanation

Philosophers of science since Nagel have been interested in the links between intertheoretic reduction and explanation, understanding and other forms of epistemic progress. Although intertheoretic reduction is widely agreed to occur in pure mathematics as well as empirical science, the relationship between reduction and explanation in the mathematical setting has rarely been investigated in a similarly serious way. This paper examines an important and well-known case: the reduction of arithmetic to set theory. I claim that the reduction is unexplanatory. In defense of this claim, I offer some evidence from mathematical practice, and I respond to contrary suggestions due to Steinhart, Maddy, Kitcher and Quine. I then show how, even if set-theoretic reductions are generally not explanatory, set theory can nevertheless serve as a legitimate and successful foundation for mathematics. Finally, some implications of my thesis for philosophy of mathematics and philosophy of science are discussed. In particular, I suggest that some reductions in mathematics are probably explanatory, and I propose that differing standards of theory acceptance might account for the apparent lack of unexplanatory reductions in the empirical sciences.     

最佳状态的政治:推动想象的诸理由

1968年常被说成改变了我们对什么是政治的感觉.对于巴黎和西方数不清的其它城市里成千上万的年轻示威者来说,政治突然从马克斯·韦伯所喜爱的那种比喻,即在硬木板上缓慢地打孔,变成了像对这样一种能力的再投资,即使人的生命可与感知现实的束缚相抗争:"成为现实主义者,就是要求不可能之物",这是另一个流行的口号.从那时起直至现在40年间,总的来说,也许除了1989年11月的柏林墙倒塌以外,政治往往是在缓慢地打孔,而不是处在想象的潮起浪涌之中.然而,尽管政治的确是一个不断出现在我们话语当中的对象,我们却很少稍事停留,对它加以定义.这正是我在这篇文章里想做的事:在对社会性(the social)的某种理解的基础上,我将首先尝试尽力完成为政治提供一个定义这项任务.然后,我将按照四种能够使其得以阐明的哲学范式,即商谈(dis-course)、判断(judgmerit)、承认(recognition)和赠予(gift),对政治的某些构成性要素(constitutive moment)进行观察.最后,我将回到政治对想象的关系这个问题上来,把它从作为1968年的一个起点的那种直接的简化(short-circuit),重新塑造为一种反思性的结构关系.     

A microswitch‐based program for promoting initial ambulation responses: An evaluation with two girls with multiple disabilities

We assessed the use of a microswitch‐based program for promoting ambulation responses by two children with multiple disabilities. The goals of the study were to: (a) evaluate the importance of the contingency between the target behavior (forward step) and the programmed consequence (preferred stimuli), (b) measure effects of the intervention on indices of happiness, and (c) assess the social validation of the procedure using 20 physiotherapists as external raters. The intervention involved the automatic delivery of preferred stimuli contingent on forward steps. Results showed that both participants improved their performance (forward steps and indices of happiness) during contingent reinforcement phases compared to baseline and noncontingent reinforcement phases. Moreover, physiotherapists rated the intervention as socially valid.     

Compassion at the mirror: Exposure to a mirror increases the efficacy of a self-compassion manipulation in enhancing soothing positive affect and heart rate variability

We tested whether a mirror could enhance the efficacy of a self-compassion manipulation in increasing soothing positive affect and heart rate variability (HRV). Eighty-six participants generated four phrases they would use to soothe and encourage their best friend. Second, they described an episode where they criticized themselves and were assigned to one of three conditions: (a) repeat the four phrases to themselves while looking at the mirror; (b) repeat the four phrases to themselves without the mirror; (c) look at themselves in the mirror without repeating the phrases. Participants in condition (a) reported higher levels of ‘soothing’ positive affect and HRV compared to participants in conditions (b) and (c). The effect of the ‘phrases at the mirror’ manipulation on soothing affect was mediated by increased common humanity. The mirror enhances the efficacy of this self-compassion manipulation in activating the soothing affect system connected with parasympathetic nervous system activity.