Dynamic perception in chess

The present study examines the dynamic aspects of perceptual processes in expert chess players. This topic is approached in terms of the anticipation processes carried out by experienced players during the encoding of chess positions. The aim of the first experiment, which used a short-term comparison task, was to stress the role of anticipation, which allows expert players to focus their attention on the area of the studied position where they expect the likely standard move to occur. The second experiment used a long-term recognition task. The results showed that expert players made many false recognitions on the new positions that could be expected from the positions presented in the preliminary study phase. Taken together, the results of the two experiments highlight the anticipatory component of expert perception.     

“Metaphysics Without Ethics is Blind”: The Legacy of Hilary Putnam

Two convictions underlie the following article. The first is that Hilary Putnam has been one of the greatest thinkers of our time, a philosopher who was able to propose groundbreaking ideas in virtually every area of philosophy. As the reader will see, the topics he tackled in his writings included questions of philosophy of science, philosophy of language, philosophy of mathematics and logic, philosophy of mind, metaethics, the fact-value dichotomy, the interpretation of Wittgenstein’s later thought, the question of relativism, the analysis of rationality, the analysis of religious experience, the character of Jewish philosophy, the interpretation of pragmatism, the elucidation of the concept of truth, the question of realism, the relationship between mind and the world. The second is that the changes some of his positions underwent, far from being a point of weakness—as some critics have sometimes felt compelled to claim—reveal the freshness and genuineness of Putnam’s way of philosophising and at the same time the essence of philosophical discussion itself.     

The fate of unattended stimuli and emotional habituation: Behavioral interference and cortical changes

The interference produced by the viewing of emotional distractors has been interpreted as evidence that emotional cues are processed in a fairly mandatory fashion, and that they divert attention from the primary ongoing task. However, few studies have examined how behavioral emotional interference varies with repeated presentation of the same emotional distractors. In two experiments, while participants were engaged in a parity judgment task, we investigated the effects of repetition of task-irrelevant emotional pictures, as reflected in both behavioral interference (Experiments 1 and 2) and neural activity (Experiment 2). Both experiments showed that the slowing of reaction times that was observed when viewing emotional, compared to neutral, scenes disappeared after only a few repetitions, suggesting diminished attention allocation to repeated emotional pictures. Conversely, in Experiment 2, neural correlates of picture processing revealed that the late positive potential (LPP) amplitude continued to be enhanced for emotional, compared to neutral, distractors despite picture repetition and the presence of a concurrent task. Altogether, these findings suggest that while evaluative processes are mandatory, and continue to engage cortico-limbic appetitive and defensive systems even after massive repetition, as suggested by the affective modulation of the LPP, attentional processes are not necessary after several repetitions of the same stimulus, as indicated by the rapid decline of behavioral emotional interference.     

Redundant visual signals boost saccade execution

The redundant signal effect (RSE) refers to the fact that human beings react more quickly to a pair of stimuli than to only one stimulus. In previous studies of the RSE in the oculomotor system, bimodal signals have been used as the goal of the saccade. In consistency with studies using manual response times (RTs), saccadic RTs have been shown to be shorter for redundant multimodal stimuli than for single unimodal stimuli. In the present experiments, we extended these findings by demonstrating an RSE in the saccadic system elicited only by unimodal visual stimuli. In addition, we found that shorter saccadic RTs were accompanied by an increased saccadic peak velocity. The present results are of relevance for neurophysiological models of saccade execution, since the boost of saccades was elicited by two visual transients (acting as a “go” signal) that were presented not at the goal of the saccade but at various other locations.     

Concurrent avoidance of shocks by pigeons pecking a key

Three pigeons were studied on concurrent, unsignaled, avoidance schedules in a two-key procedure. Shock-shock intervals were two seconds in both schedules. The response-shock interval on one key was always 22 seconds, while the response-shock interval associated with the other key was varied from 7 to 52 seconds in different experimental conditions. Response rates on the key associated with the varied schedule tended to decrease when the response-shock interval length was increased. Responding on the key associated with the constant schedule was not systematically affected.     

Influence of Expertise on the Intentional Transfer of Motor Skill

Intentional transfer of expert knowledge is an important issue in cognitive science and motor skills. How subjects deliberately transfer expertise in karate when learning a closely related motor skill (tai chi) was examined in this study. Subjects (N = 20) learned a videotaped sequence of self-defense movements, evaluated their learning, and then performed the sequence. Self-regulation of learning is believed to be central to effective transfer. The measures of self-regulation were accuracy of self-evaluation, video use, and approach to learning. Results showed that unlike novices, experts used self-regulation, learning strategies, and the video player in more complex ways in self-regulation. Experts, as compared with novices, demonstrated their greater knowledge through the higher quality of their performance and their better comprehension of movement meaning; but both groups recalled an equal number of moments, suggesting that both experts and novices transferred general knowledge about learning.