Associative interference with taste aversions after contextual discrimination learning

In two experiments, rats were first given discriminative training with two distinctive contexts, such that a flavor was paired with lithium chloride (LiCl) in one context, alternating with presentations of the flavor alone in another context. Contextual control of the fluid ingestion was observed in that rats reduced the fluid intake in the LiCl-paired context but drank the solution in the context never paired with lithium. Having learned this discrimination, the rats were now given a second flavor in their home cage before being injected with LiCl and transferred to the previously lithium-paired context. In Experiment 1, the acquisition of an aversion to the novel flavor was blocked when this flavor and the contextual cues are conditioned as a compound. In Experiment 2, the blocking effect and the conditional control over fluid consumption were abolished when the associative strength of the LiCl-paired context had been extinguished by exposing the animals to water in the contexts after discriminative training. These results are interpreted as evidence that context dependency of conditioned taste aversions is mediated by a summative effect of the context–LiCl and flavor–LiCl associations.     

The Other Self: Psychopathology and Literature

The figure of the "double" or the other self is an important topic in the history of literature. Many centuries before Jean Paul Richter coined the term, "doppelg?nger," at the beginning of the Romantic Movement in the year 1796, it is possible to find the figure of the double in myths and legends. The issue of the double emphaszses the contradictory character of the human being and invokes a sinister dimension of the psychological world, what has been called in German as "umheimlich." However, does multiciplicity always involve pathology? Related to this figure in literary history, a new perspective from clinical psychology called "dialogical self" defines the self as a multi-voice reality. Along the same line, postmodernist psychology considers the self a discursive construction. From these perspectives, the "self" is situated a long way away from the classical essential conception of the self. In this paper, we review briefly some important landmarks of the figure of the double in the literature, and we compare the coincidences of the "double" experiencies described in literature with the experiences of our patients. Finally, we discuss how this literary tradition can help us to understand new psychological perspectives.     

Transfer of control between causal predictive judgments and instrumental responding

Four experiments were conducted to explore outcome-specific transfer from causal predictive judgments to instrumental responding. A video game was designed in which participants had to defend Andalusia from navy and air force attacks. First, they learned the relationship between two instrumental responses (two key on a standard keyboard) and two different outcomes (destruction of the ships or destruction of the planes). Then they learned to predict which of two different stimuli predicted which outcome. Finally, they had the opportunity of making either of the two instrumental responses in the presence of either stimulus. Transfer was shown as a preference for the response that shared an outcome with the current stimulus. The presentation of the stimulus during the test produced a decrease in the overall rate of response. Responding to a neutral stimulus in Experiments 2 and 3 suggested that this overall decrease in responding was due to a combination of the time needed to process the meaning of the stimulus and the activation of the representation of the outcome in the presence of the stimulus during the test. Transfer between predictive judgments and instrumental responding mirrors the outcome-specific Pavlovian instrumental transfer observed in conditioning studies with rats.     

Cooperative responding in rats maintained by fixed‐ and variable‐ratio schedules

The present study investigated the effects of fixed‐ratio (FR) and variable‐ratio (VR) reinforcement schedules on patterns of cooperative responding in pairs of rats. Experiment 1 arranged FR 1, FR 10, and VR 10 schedules to establish cooperative responding (water delivery depended on the joint responding of two rats). Cooperative response rates and proportions were higher under intermittent schedules than under continuous reinforcement. The FR 10 schedule generated a break‐and‐run pattern, whereas the VR 10 schedule generated a relatively high and constant rate pattern. Experiment 2 evaluated the effects of parametric manipulations of FR and VR schedules on cooperative responding. Rates and proportions of cooperative responding generally increased between ratio sizes of 1 and 5 but showed no consistent trend as the ratio increased from 5 to 10. Experiment 3 contrasted cooperative responding between an FR6 schedule and a yoked control schedule. Coordinated behavior occurred at a higher rate under the former schedule. The present study showed that external consequences and the schedules under which the delivery of these consequences are based, select patterns of coordinated behavior.     

Voting by Eliminating Quantifiers

Mathematical theory of voting and social choice has attracted much attention. In the general setting one can view social choice as a method of aggregating individual, often conflicting preferences and making a choice that is the best compromise. How preferences are expressed and what is the “best compromise” varies and heavily depends on a particular situation. The method we propose in this paper depends on expressing individual preferences of voters and specifying properties of the resulting ranking by means of first-order formulas. Then, as a technical tool, we use methods of second-order quantifier elimination to analyze and compute results of voting. We show how to specify voting, how to compute resulting rankings and how to verify voting protocols.     

Testing the Δ-∑ hypothesis in the suboptimal choice task: Same delta with different probabilities of reinforcement

In a concurrent-chain procedure, pigeons choose between 2 initial-link stimuli; one is followed by terminal link stimuli that signal reliably whether food will be delivered after a delay; the other is followed by terminal link stimuli that do not signal whether food will be delivered after the delay. Pigeons prefer the former alternative even when it yields a lower overall probability of food. Recently, we proposed the Delta-Sigma (∆-∑) hypothesis to explain the effect: Preference depends on the difference (∆) between the reinforcement probabilities associated with the terminal link stimuli, and the overall probability of reinforcement (∑) associated with the alternative. The hypothesis predicts that, for constant ∑, animals should prefer alternatives with greater ∆ values regardless of the specific probabilities of reinforcement that determine ∆. In 2 experiments, we tested this prediction by comparing a ∆ = .5 against a ∆ = 0 alternative, with the former obtained with different pairs of reinforcement probabilities across conditions. The results supported the hypothesis when the 2 probabilities defining ∆ were significantly greater than 0, but not when one of them was close to 0. The results challenge our theoretical accounts of suboptimal choice and the variables considered to determine pigeons’ preference.     

Temporal preparation,response inhibition and impulsivity

Temporal preparation and impulsivity involve overlapping neural structures (prefrontal cortex) and cognitive functions (response inhibition and time perception), however, their interrelations had not been investigated. We studied such interrelations by comparing the performance of groups with low vs. high non-clinical trait impulsivity during a temporal preparation go no-go task. This task measured, in less than 10 min, how response inhibition was influenced both by temporal orienting of attention (guided by predictive temporal cues) and by sequential effects (produced by repetition/alternation of the duration of preparatory intervals in consecutive trials). The results showed that sequential effects produced dissociable patterns of temporal preparation as a function of impulsivity. Sequential effects facilitated both response speed (reaction times – RTs – to the go condition) and response inhibition (false alarms to the no-go condition) selectively in the low impulsivity group. In the high impulsivity group, in contrast, sequential effects only improved RTs but not response inhibition. We concluded that both excitatory and inhibitory processing may be enhanced concurrently by sequential effects, which enables the temporal preparation of fast and controlled responses. Impulsivity could hence be related to less efficient temporal preparation of that inhibitory processing.     

Alcohol use as a strategy for obtaining nonconsensual sexual relations: incidence in Spanish university students and relation to rape myths acceptance

This study analyzed the strategy of college men who give alcohol to girls to facilitate their acceptance when pursuing sexual relationships. It also studied the role of attitudes towards sexual assaults (rape myths) in the social perception of this practice; finally, this research examined how the fact that, in some cases, college women accept taking alcohol in their interactions with college men was perceived. Participants were 349 heterosexual students (154 men and 195 women) from the University of Granada. 28% of males reported having given alcohol to females in order to have sexual contacts with them, while 44% of females acknowledged having suffered this practice. Men, compared to women, were more favourable to this practice; however, this effect was moderated by their rape myths endorsements. It was also found that males and, in general, those participants who endorsed rape myths, tended to consider that girls who accept alcohol in their interactions with boys are promiscuous.     

An Analysis of Extinction-Cue Features in the Reduction of Operant Behavior Relapse

The Psychological Record - The present free operant conditioning experiments with rats examined the impact of manipulating different traits of an extinction-cue on ABA renewal. All rats were...