Control and synchronization of laser bursting and its implications in neuroscience

We present experimental and numerical evidence of control and synchronization of burst events in modulated CO₂ lasers. Bursts appear randomly in each laser as trains of large amplitude spikes intercalated by a small amplitude chaotic regime. Experimental data and model display the frequency locking of bursts in a suitable interval of coupling strengths. The analogy with neuronal bursting will also be discussed in view of the role of bursting synchronization in cognitive functions.     

New knowledge for old credences: Asymmetric information search about in-group and out-group members

Three experiments examined how people gather information on in-group and out-group members. Previous studies have revealed that category-based expectancies bias the hypothesis-testing process towards confirmation through the use of asymmetric-confirming questions (which are queries where the replies supporting the prior expectancies are more informative than those falsifying them). However, to date there is no empirical investigation of the use of such a question-asking strategy in an intergroup context. In the present studies, participants were asked to produce (Study 1) or to choose (Studies 2 and 3) questions in order to investigate the presence of various traits in an in-group or an out-group member. Traits were manipulated by valence and typicality. The results revealed that category-based expectancies do not always lead to asymmetric-confirming testing: whereas participants tended to ask questions that confirmed positive in-group and negative out-group stereotypical attributes, they used a more symmetric strategy when testing for the presence of negative in-group or positive out-group traits. Moreover, Study 3 also revealed a moderation effect of in-group identification. The findings point to the role played by motivational factors associated with preserving a positive social identity. Possible consequences of these hypothesis-testing processes in preserving a positive social identity for intergroup relations are discussed.     

Rapid and persistent suppression of feeding behavior induced by sensitization training in Aplysia

In Aplysia, noxious stimuli induce sensitization of defensive responses. However, it remains largely unknown whether such stimuli also alter nondefensive behaviors. In this study, we examined the effects of noxious stimuli on feeding. Strong electric shocks, capable of inducing sensitization, also led to the suppression of feeding. The use of multiple training protocols revealed that the time course of the suppression of feeding was analogous to that of sensitization. In addition, the suppression of feeding was present only at the time points in which sensitization was expressed. These results suggest that, in Aplysia, noxious stimuli may produce concurrent changes in neural circuits controlling both defensive and nondefensive behaviors.     

Shame in Relation to the Body,Sex, and Death: A Clinical Exploration of the Psychotic Levels of Shame

This paper explores the topic of shame in relation to the body, viewing it as the expression of a basic conflict that threatens to obstruct the growth of personality by breaking up the body-mind relationship. The paper presents the psychoanalysis of a psychotic patient whose paranoid shame was associated with the delusion of being noticed. During this analysis, the patient's bodily manifestations and hatred were acknowledged as related to his getting closer to an authentic existence of his own. Particular emphasis is given to the analyst's involvement in the analytic process, in the form of both bodily countertransference and dream activation. The containment and working-through of concrete aspects of hatred and death anxiety, together with the analysand's recognizing the value of sensory perception of his own body, fostered an abatement of symptoms, including his tendency to flee and to attempt to burst the confines of his body. The activation of a connection with the body seems a prerequisite to the development of abstract thinking. The paper describes similar dynamics in two vignettes of less dramatic clinical cases.     

Analytic Calculi for Circular Concepts by Finite Revision

The paper introduces Hilbert– and Gentzen-style calculi which correspond to systems ${\mathsf{C}_{n}}$ from Gupta and Belnap [3]. Systems ${\mathsf{C}_{n}}$ were shown to be sound and complete with respect to the semantics of finite revision. Here, it is shown that Gentzen-style systems ${\mathsf{GC}_{n}}$ admit a syntactic proof of cut elimination. As a consequence, it follows that they are consistent.     

Modification of EEG power spectra and EEG connectivity in autobiographical memory: a sLORETA study

The aim of the present study was to explore the modifications of scalp EEG power spectra and EEG connectivity during the autobiographical memory test (AM-T) and during the retrieval of an autobiographical event (the high school final examination, Task 2). Seventeen healthy volunteers were enrolled (9 women and 8 men, mean age 23.4 ± 2.8 years, range 19–30). EEG was recorded at baseline and while performing the autobiographical memory (AM) tasks, by means of 19 surface electrodes and a nasopharyngeal electrode. EEG analysis was conducted by means of the standardized LOw Resolution Electric Tomography (sLORETA) software. Power spectra and lagged EEG coherence were compared between EEG acquired during the memory tasks and baseline recording. The frequency bands considered were as follows: delta (0.5–4 Hz); theta (4.5–7.5 Hz); alpha (8–12.5 Hz); beta1 (13–17.5 Hz); beta2 (18–30 Hz); gamma (30.5–60 Hz). During AM-T, we observed a significant delta power increase in left frontal and midline cortices (T = 3.554; p < 0.05) and increased EEG connectivity in delta band in prefrontal, temporal, parietal, and occipital areas, and for gamma bands in the left temporo-parietal regions (T = 4.154; p < 0.05). In Task 2, we measured an increased power in the gamma band located in the left posterior midline areas (T = 3.960; p < 0.05) and a significant increase in delta band connectivity in the prefrontal, temporal, parietal, and occipital areas, and in the gamma band involving right temporo-parietal areas (T = 4.579; p < 0.05). These results indicate that AM retrieval engages in a complex network which is mediated by both low- (delta) and high-frequency (gamma) EEG bands.     

How does our search engine “see” the world? The case of amodal completion

This article illustrates a dissociation between the perceived attributes of an object and the ability of those attributes to guide the deployment of attention in visual search. Orientation is an attribute that guides search. Thus, a vertical line will “pop out” amid horizontal distractors. Amodal completion can create perceptually convincing oriented stimuli when two elements appear to form a complete object partially hidden behind an occluder. Previous work (e.g., Rensink &; Enns, Vision Research, 38, 2489–2505, 1998) has shown a preattentive role for amodal completion in search tasks. Here, we show that orientation based on perceptually compelling amodal completion may fail to guide attention. The broader conclusion is that introspection is a poor guide to the capabilities of our internal search engine.     

PRIMITIVE MENTAL STATES AND THE BODY: A PERSONAL VIEW OF ARMANDO B. FERRARI'S CONCRETE ORIGINAL OBJECT

The author explores some psychoanalytic hypotheses about primitive mental states and their implications for a direct focus on body experience in clinical work. Some aspects of current clinical research about the patient's difficulty in achieving awareness of his emotional life as it emerges from object relations are presented, and this problem is viewed in connection with the relation of the analysand to his own body and to his capacity to pass through the different levels of mental elaboration, from motor discharge to abstraction. Ferrari's theories on the body—mind relationship are discussed and compared with the work of other authors. Ferrari calls the body the Concrete Original Object to indicate that it is the first source, differing from person to person, from which mental phenomena are generated and against which they are constantly measured. A clinical case serves as an illustration of the importance of the perception of the body for the birth of genuine, non-imitative mental activity.