Consequence Mining

The standard semantic definition of consequence with respect to a selected set X of symbols, in terms of truth preservation under replacement (Bolzano) or reinterpretation (Tarski) of symbols outside X, yields a function mapping X to a consequence relation \(\Rightarrow_X\). We investigate a function going in the other direction, thus extracting the constants of a given consequence relation, and we show that this function (a) retrieves the usual logical constants from the usual logical consequence relations, and (b) is an inverse to—more precisely, forms a Galois connection with—the Bolzano–Tarski function.     

Just ignore or counterattack? On the effects of different strategies for dealing with political attacks

During political races, candidates have to decide how to deal with the negative remarks from opposing candidates: just ignore or counterattack? In two studies, we investigated some of the consequences of this choice. In Study 1, participants were presented with a political candidate who systematically attacked his opponent and with the reactions of the attacked candidate: across conditions, the attacked candidate only focused on his political program or counterattacked. Results showed an overt condemnation of the choice to counterattack but a higher spontaneous conformity toward the candidate who counterattacked. Study 2 replicated and extended these results indicating that the gender of the attacked candidate did not affect the results. Moreover, Study 2 showed that conformity toward the attacked candidate was positively related to the predicted chances of winning the election. Results are discussed in relation to their theoretical and applied implications. Copyright © 2012 John Wiley & Sons, Ltd.     

TRACX: a recognition-based connectionist framework for sequence segmentation and chunk extraction

Individuals of all ages extract structure from the sequences of patterns they encounter in their environment, an ability that is at the very heart of cognition. Exactly what underlies this ability has been the subject of much debate over the years. A novel mechanism, implicit chunk recognition (ICR), is proposed for sequence segmentation and chunk extraction. The mechanism relies on the recognition of previously encountered subsequences (chunks) in the input rather than on the prediction of upcoming items in the input sequence. A connectionist autoassociator model of ICR, truncated recursive autoassociative chunk extractor (TRACX), is presented in which chunks are extracted by means of truncated recursion. The performance and robustness of the model is demonstrated in a series of 9 simulations of empirical data, covering a wide range of phenomena from the infant statistical learning and adult implicit learning literatures, as well as 2 simulations demonstrating the model's ability to generalize to new input and to develop internal representations whose structure reflects that of the items in the input sequence. TRACX outperforms PARSER (Perruchet & Vintner, 1998) and the simple recurrent network (SRN, Cleeremans & McClelland, 1991) in matching human sequence segmentation on existing data. A new study is presented exploring 8-month-olds' use of backward transitional probabilities to segment auditory sequences.     

Integration of visual information for saccade production

To foveate a visual target, subjects usually execute a primary hypometric saccade (S1) bringing the target in perifoveal vision, followed by a corrective saccade (S2) or by more than one S2. It is still debated to what extent these S2 are pre-programmed or dependent only on post-saccadic retinal error. To answer this question, we used a visually-triggered saccade task in which target position and target visibility were manipulated. In one-third of the trials, the target was slightly displaced at S1 onset (so-called double step paradigm) and was maintained until the end of S1, until the start of the first S2 or until the end of the trial. Experiments took place in two visual environments: in the dark and in a dimly lit room with a visible random square background. The results showed that S2 were less accurate for shortest target durations. The duration of post-saccadic visual integration thus appears as the main factor responsible for corrective saccade accuracy. We also found that the visual context modulates primary saccade accuracy, especially for the most hypometric subjects. These findings suggest that the saccadic system is sensitive to the visual properties of the environment and uses different strategies to maintain final gaze accuracy.     

Medically Defining,Screening, and Treating Conduct Disorder: A French Controversy

For several decades, the use of psychotropic medication has either been regarded as a medical issue or an example of the medicalization of social problems. As the publication in 2005 of a knowledge synthesis on conduct disorder in children and adolescents and the reply of the «Pas de zéro de conduite» collaboration (literally: No F for Conduct) was a highly important event in the French mental health scene, it deserves a thorough discussion. In the hope of improving the practices and policies targeting children and their families, it is essential to gain a better understanding of the bones of contention between the proponents and opponents of a medical or rather biosocial model. To achieve this, we first analyze how this model assigns a central role to certain disorders defined and diagnosed based on constellations of symptoms. We then identify five dimensions which seem to hold center stage in the controversy: genetic susceptibility, neurocognitive deficits and temperament, the familial and social environment seen as a reservoir of stressors, large-scale screening for disorders using simple instruments and multi-modal treatments, including psychotropic medication. We take an interest in the French debate as this allows us to stand back from the models prevailing in North America. It also underscores the importance of multidisciplinary thinking and social sciences when elaborating clinical or political mental health guidelines.     

Decay uncovered in nonverbal short-term memory

Decay theory posits that memory traces gradually fade away over the passage of time unless they are actively rehearsed. Much recent work exploring verbal short-term memory has challenged this theory, but there does appear to be evidence for trace decay in nonverbal auditory short-term memory. Numerous discrimination studies have reported a performance decline as the interval separating two tones is increased, consistent with a decay process. However, most of this tone comparison research can be explained in other ways, without reference to decay, and these alternative accounts were tested in the present study. In Experiment 1, signals were employed toward the end of extended retention intervals to ensure that listeners were alert to the presence and frequency content of the memoranda. In Experiment 2, a mask stimulus was employed in an attempt to distinguish between a highly detailed sensory trace and a longer-lasting short-term memory, and the distinctiveness of the stimuli was varied. Despite these precautions, slow-acting trace decay was observed. It therefore appears that the mere passage of time can lead to forgetting in some forms of short-term memory.