EFFECTS OF PROBLEM DIFFICULTY AND REINFORCER QUALITY ON TIME ALLOCATED TO CONCURRENT ARITHMETIC PROBLEMS

Students with learning difficulties participated in two studies that analyzed the effects of problem difficulty and reinforcer quality upon time allocated to two sets of arithmetic problems reinforced according to a concurrent variable-interval 30-s variable-interval 120-s schedule. In Study 1, high- and low-difficulty arithmetic problems were systematically combined with rich and lean concurrent schedules (nickels used as reinforcers) across conditions using a single-subject design. The pairing of the high-difficulty problems with the richer schedule failed to offset time allocated to that alternative. Study 2 investigated the interactive effects of problem difficulty and reinforcer quality (nickels vs. program money) upon time allocation to arithmetic problems maintained by the concurrent schedules of reinforcement. Unlike problem difficulty, the pairing of the lesser quality reinforcer (program money) with the richer schedule reduced the time allocated to that alternative. The magnitude of this effect was greatest when combined with the low-difficulty problems. These studies have important implications for a matching law analysis of asymmetrical reinforcement variables that influence time allocation.     

Undecidability,incompleteness and Arnol'd problems

We present some recent technical results of us on the incompleteness of classical analysis and then discuss our work on the Arnol'd decision problems for the stability of fixed points of dynamical systems.Partially supported by FAPESP and CNP_q (Brazil, Philosophy Section).     

Cut-Free Tableau Calculi for some Intuitionistic Modal Logics

In this paper we provide cut-free tableau calculi for the intuitionistic modal logics IK, ID, IT, i.e. the intuitionistic analogues of the classical modal systems K, D and T. Further, we analyse the necessity of duplicating formulas to which rules are applied. In order to develop these calculi we extend to the modal case some ideas presented by Miglioli, Moscato and Ornaghi for intuitionistic logic. Specifically, we enlarge the language with the new signs Fc and CR near to the usual signs T and F. In this work we establish the soundness and completeness theorems for these calculi with respect to the Kripke semantics proposed by Fischer Servi.     

Improvisation: The Astonishing Bridge to Our Inner Music

Musical improvisation is the expressive capacity of a performer fostered by access to their own “productive” (creative) or “reproductive” (mnestic) tonal imagery: a field of consciousness that includes experiences, images that are internal, combined, distorted, associated, or in competition between themselves. In the highly original form of life that is jazz, narrating means directing time: a time of epiphanies and introversions, of intuitions and revelations, of syncopated rhythms and aesthetic insights, which appear and disappear on the edges of interference between consciousness and the unconscious. The performing urgency of gestures, voices, and sounds, although arranged in the same scene, highlights the difference in individual time. In this intense activity of opposition and resolution the experience becomes an unstable territory that rests on the capacity of the body to remember, decide, anticipate, and invent. The ego reveals itself to be an emerging representation of our nerve structures and, even if conscious organization continues to be attributed to it, its role is not at all crucial. Unity, if anything, means coordination. The conscious ego is the expression of the body. In its ultimate form its unity is a biological problem.     

Serial dependence in position occurs at the time of perception

Observers perceive objects in the world as stable over space and time, even though the visual experience of those objects is often discontinuous and distorted due to masking, occlusion, camouflage, or noise. How are we able to easily and quickly achieve stable perception in spite of this constantly changing visual input? It was previously shown that observers experience serial dependence in the perception of features and objects, an effect that extends up to 15 seconds back in time. Here, we asked whether the visual system utilizes an object’s prior physical location to inform future position assignments in order to maximize location stability of an object over time. To test this, we presented subjects with small targets at random angular locations relative to central fixation in the peripheral visual field. Subjects reported the perceived location of the target on each trial by adjusting a cursor’s position to match its location. Subjects made consistent errors when reporting the perceived position of the target on the current trial, mislocalizing it toward the position of the target in the preceding two trials (Experiment 1). This pull in position perception occurred even when a response was not required on the previous trial (Experiment 2). In addition, we show that serial dependence in perceived position occurs immediately after stimulus presentation, and it is a fast stabilization mechanism that does not require a delay (Experiment 3). This indicates that serial dependence occurs for position representations and facilitates the stable perception of objects in space. Taken together with previous work, our results show that serial dependence occurs at many stages of visual processing, from initial position assignment to object categorization.     

Spiritual development: understanding and importance in schools: an analysis based on statements made by school directors from Valparaíso,Chile

Chile’s General Law of Education states that one of the purposes of education is the spiritual development of all its schooled population. Furthermore, guidelines in Chile’s education system place school directors as key players in student’s learning. This article presents the results of a research involving school directors from Valparaíso, Chile. The aim of this research was to identify how directors of secular and religious schools understand their students’ spiritual development. We studied this aspect in particular through semi-structured interviews conducted with 20 participants. Results show that directors understand spirituality as a typically human ability that can be strengthened in schools and, thus, they believe it to be highly important in schools. In addition, they see a strong relation between spiritual development and ethical and moral development. This study also shows differences in how secular and religious schools’ directors understand this relation. This opens the way for more in-depth analysis regarding spiritual development in Chile’s education system, especially considering that directors generally believe it to be a part of a holistic and quality education.     

Intracellular calcium chelation and pharmacological SERCA inhibition of Ca2+ pump in the insular cortex differentially affect taste aversive memory formation and retrieval

Variation in intracellular calcium concentration regulates the induction of long-term synaptic plasticity and is associated with a variety of memory/retrieval and learning paradigms. Accordingly, impaired calcium mobilization from internal deposits affects synaptic plasticity and cognition in the aged brain. During taste memory formation several proteins are modulated directly or indirectly by calcium, and recent evidence suggests the importance of calcium buffering and the role of intracellular calcium deposits during cognitive processes. Thus, the main goal of this research was to study the consequence of hampering changes in cytoplasmic calcium and inhibiting SERCA activity by BAPTA-AM and thapsigargin treatments, respectively, in the insular cortex during different stages of taste memory formation. Using conditioned taste aversion (CTA), we found differential effects of BAPTA-AM and thapsigargin infusions before and after gustatory stimulation, as well as during taste aversive memory consolidation; BAPTA-AM, but not thapsigargin, attenuates acquisition and/or consolidation of CTA, but neither compound affects taste aversive memory retrieval. These results point to the importance of intracellular calcium dynamics in the insular cortex during different stages of taste aversive memory formation.     

An introduction to the 2011 National Multicultural Conference & Summit keynote addresses

This article provides and introduction to the 2011 National Multicultural Conference & Summit Keynote Addresses. The authors explain that they chose to focus on the tension and possibilities within multicultural psychology at the seventh biennial National Multicultural Conference & Summit (NMCS), which was held on January 27-28, 2011, at The Westin-Seattle Hotel. During the 2-day conference, nearly 900 attendees engaged with one another and heard from experts in the field as we focused on the theme, "Unification through Diversity: Bridging Psychological Science & Practice in the Public Interest. Two key sets of presentations are highlighted.     

Short-term effects of a multi-disciplinary cardiac rehabilitation programme on psychological well-being, exercise capacity and weight in a sample of obese in-patients with coronary heart disease: a practice-level study

Given that many patients referred to cardiac rehabilitation (CR) are obese, diet therapy, exercise training, nutritional and psychological counselling for both obesity and psychological distress should be included as important components in all CR programmes. In this practice-level, observational study we evaluated the short-term within-group effects of a four-week multi-factorial inpatient CR programme specifically addressed to weight loss, fitness improvement and psychological health increase on 176 obese in-patients with coronary heart disease (CHD). Outcome measures were exercise capacity measured with estimated metabolic equivalents (METs), body mass index (BMI) and psychological well-being (PGWBI). Results show statistically significant improvements in all the PGWBI sub-scales and total score, except in general health (p = 0.393). No moderation effects were found for BMI class, age, diabetes and ejection fraction (EF). METs significantly increased by 30.3% (p < 0.001) and BMI decreased by 1.37 points (p < 0.001). Significant correlations were found between BMI and weight reductions with PGWBI anxiety and total score improvements. This multi-disciplinary CR programme including diet therapy, exercise training and psychological counselling provides indication for short-term within-group effectiveness on functional exercise capacity, BMI and PGWBI in a sample of obese in-patients with CHD. However, controlled studies are needed to corroborate the results we found.     

Preference for unreliable reinforcement in children with mental retardation: the role of conditioned reinforcement

We examined the effects of conditioned reinforcement on children's choice between reliable (100%) and unreliable (50%) reinforcement under various stimulus conditions in a concurrent-chains procedure. The study was conducted across three experiments. Experiments 1 and 2 were conducted under conditions similar to basic laboratory work and consisted of participants selecting from one of two black boxes (placed on a table) that were correlated with different reinforcement schedules. In Experiment 3, we assessed a participant's preference for unreliable reinforcement during conditions in which the target responses were aggression and mands. Results of the three experiments showed that the participants preferred unreliable reinforcement under certain conditions. Findings are discussed regarding the role of specific stimuli (i.e., items correlated with a reinforcement schedule, adult reactions) as conditioned reinforcers and how they may influence children's preference for a response (e.g., aggression, self-injury) that produces reinforcement on a leaner schedule than a socially desirable response (e.g., mands).