On the Closure Properties of the Class of Full G-models of a Deductive System

In this paper we consider the structure of the class FGModS of full generalized models of a deductive system S from a universal-algebraic point of view, and the structure of the set of all the full generalized models of S on a fixed algebra A from the lattice-theoretical point of view; this set is represented by the lattice FACS_s A of all algebraic closed-set systems C on A such that (A, C) ε FGModS. We relate some properties of these structures with tipically logical properties of the sentential logic S. The main algebraic properties we consider are the closure of FGModS under substructures and under reduced products, and the property that for any A the lattice FACS_s A is a complete sublattice of the lattice of all algebraic closed-set systems over A. The logical properties are the existence of a fully adequate Gentzen system for S, the Local Deduction Theorem and the Deduction Theorem for S. Some of the results are established for arbitrary deductive systems, while some are found to hold only for deductive systems in more restricted classes like the protoalgebraic or the weakly algebraizable ones. The paper ends with a section on examples and counterexamples. Dedicated to the memory of Willem Johannes Blok     

Social anxiety and problematic cannabis use: evaluating the moderating role of stress reactivity and perceived coping

Despite epidemiological reports indicating an association between social anxiety disorder (SAD) and cannabis use disorders (CUD), there is a paucity of research exploring the nature of this relationship. The present investigation examined potential moderators of this relationship that are consistent with a tension-reduction model of addiction. Specifically, physiological reactivity to stress and perceived coping with stress were evaluated as moderators of the relation between symptoms of SAD and CUD. Physiological (SCR) and subjective (perceived coping) responses to unpredictable white noise bursts were collected from non-clinical participants (n=123). Lifetime symptoms of CUD and anxiety disorders were assessed using a structured diagnostic interview. CUD symptomatology was associated with symptoms of SAD but not with symptoms of any other anxiety disorder. Only perceived coping to unpredictable stimuli moderated the relationship between SAD and CUD symptoms. Findings are discussed in the context of tension-reduction models of co-occurring social anxiety and problematic cannabis use.     

How color enhances visual memory for natural scenes

We offer a framework for understanding how color operates to improve visual memory for images of the natural environment, and we present an extensive data set that quantifies the contribution of color in the encoding and recognition phases. Using a continuous recognition task with colored and monochrome gray-scale images of natural scenes at short exposure durations, we found that color enhances recognition memory by conferring an advantage during encoding and by strengthening the encoding-specificity effect. Furthermore, because the pattern of performance was similar at all exposure durations, and because form and color are processed in different areas of cortex, the results imply that color must be bound as an integral part of the representation at the earliest stages of processing.     

Role of muscarinic M1 receptors in inhibitory avoidance and contextual fear conditioning

The objective of the present study was to observe the effects of pre-training or post-training administration of dicyclomine, a M1 muscarinic antagonist, on inhibitory avoidance (IA) and contextual fear conditioning (CFC) and to investigate if the effects observed with the pre-training administration of dicyclomine are state-dependent. For each behavioral procedure (IA and CFC) groups of Wistar male rats were treated with saline or dicyclomine either 30 min before training (pre-training), immediately after training or 30 min before training/30 min before test (pre-training/pre-test). The animals were tested 24 h after training. The acquisition of IA and CFC was impaired by pre-training administration of dicyclomine. The consolidation of both tasks was not affected by dicyclomine given immediately after training. Pre-training/pre-test administration of dicyclomine impaired both tasks, an effect similar to that observed in the group which only received pre-training administration. Pre-test treatment induced dissociation between both tasks, impairing CFC retrieval, without interfering with the animals avoidance response. These results show that the dicyclomine did not affect IA and CFC consolidation, suggesting specific involvement of M1 muscarinic receptor only in acquisition these tasks, and these effects was not state-dependent. However, it is possible that the retrieval of these tasks may be mediated, at least in part, by different neurochemical mechanisms and may be dissociated by dicyclomine.     

Sex differences in regret: all for love or some for lust?

Few sex differences in regret or counterfactual thinking are evident in past research. The authors discovered a sex difference in regret that is both domain-specific (i.e., unique to romantic relationships) and interpretable within a convergence of theories of evolution and regulatory focus. Three studies showed that within romantic relationships, men emphasize regrets of inaction over action (which correspond to promotion vs. prevention goals, respectively), whereas women report regrets of inaction and action with equivalent frequency. Sex differences were not evident in other interpersonal regrets (friendship, parental, sibling interactions) and were not moderated by relationship status. Although the sex difference was evident in regrets centering on both sexual and nonsexual relationship aspects, it was substantially larger for sexual regrets. These findings underscore the utility of applying an evolutionary perspective to better understand goal-regulating, cognitive processes.     

Narrow-band 1, 2, 3, 4, 8, 16, 24, 32, 48, 64, and 96 cycles/360 degrees angular frequency filters

We measured human frequency response functions for eleven angular frequency filters using a forced-choice procedure in a supra-threshold summation paradigm. Each of the eleven functions of 17 experimental conditions was measured 4-9 times among 12 observers. Results show that, for the arbitrarily selected filter phases, maximum summation effect occurred at test frequency for all filters. These results lead to the conclusion that there are narrow-band angular frequency filters operating in human visual system mostly through summation surrounded by inhibition at the specific test frequency ranges. Our previous suggestion (Simas and Santos, 2002), arguing that summation for the higher angular frequency filters should occur if background angular frequency contrast were set to a maximum of 5 times the test frequency threshold, was supported.