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One experiment in human predictive learning explored the impact of a context change on attention to contexts and predictive ratings controlled by the cue. In Context A: cue X was paired with an outcome four times, while cue Y was presented without an outcome four times in Context B:. In both contexts filler cues were presented without the outcome. During the test, target cues X and Y were presented either in the context where they were trained, or in the alternative context. With the context change expectation of the outcome X, expressed as predictive ratings, decreased in the presence of X and increased in the presence of Y. Looking at the contexts, expressed as a percentage of the overall gaze dwell time on a trial, was high across the four training trials, and increased with the context change. Results suggest that the presentation of unexpected information leads to increases in attention to contextual cues. Implications for contextual control of behavior are discussed. [ABSTRACT FROM AUTHOR]

An experiment on taste sensory analysis was conducted to explore the effects of manipulating signal intensity and response incentives on sensitivity and decision processes when evaluating basic tastes under high ecological validity conditions. Salt concentration (0.07%, 0.1% or 0.75%) and payoff matrices that were intended to produce lenient, conservative, or neutral response strategies were manipulated in a full factorial between-subjects design. Salt concentration only affected the sensory process (sensory index A’) while payoffs only affected the decision process (decision index B’ D ). The effect of the payoff manipulation on the decision index was symmetrical for lenient and conservative induced response strategies, though less extreme than the values predicted by Signal Detection Theory for an optimal performance under unbalanced payoffs. [ABSTRACT FROM AUTHOR]

Participants were trained in a human predictive learning task in which they had to predict whether the ingestion of a given food (cue) by the imaginary customer of an imaginary restaurant (context) was followed by gastric malaise (outcome). One food was always followed by gastric malaise in one of the contexts, while other foods were not followed by gastric malaise in the same, or in an alternative context. Predictive responses and eye-fixations were recorded throughout the 48 training trials with each cue involved in the task. In agreement with the predictions of the Attentional Theory of Context Processing, attention to the contexts measured through eye-fixations decreased while attention to the cues increased as training progressed. The results of this study give support to the idea that contexts are actively processed at the beginning of acquisition, and that this processing decreases as training increases. [ABSTRACT FROM AUTHOR]

An experiment on taste sensory analysis of an artificially arranged compound of salty and sour flavors was conducted with the goal of evaluating sensory performance to a mixture of flavors akin to natural food, but that allows for keeping a higher experimental control than natural foods do. Participants performed a detection task in which the concentration of salt was manipulated between-subjects (from 0.07 to 0.75%). A procedure based on a dissociative model that allows for obtaining independent measures of sensitivity and criterion performance was used. In general, sensitivity index increased with the increase in signal salience, with actual performance approaching a Weibull distribution. A slight but reliable lenient response bias was found regardless of the salt concentration. The relevance of using independent measures of sensitivity and bias in sensory evaluation of complex compounds, and its relevance for sensory analysis of food is discussed. Practical Applications In tasting situations, perception seems to be easily influenced by cognitive factors and different response biases might appear, modifying the response criterion location. Difficulty of discrimination may also increases by qualitative changes that occur in taste mixtures. Signal Detection Theory allows the measurement of both: sensory and nonsensory components. Taking apart cognitive and sensory components is central to uncovering small differences in sensory qualities and developing accurate models of perception. This approach is of special interest to study the psychological processes involved in tasting situations, including the evaluation of training programs conducted to improve tasters' discriminative abilities. In addition, function modelization has important implications for the area of perceptual research since psychophysical functions for binary compounds as it allows conducting predictions about interaction effects between studied components in complex stimuli. [ABSTRACT FROM AUTHOR]

Abstract: An experiment evaluated a Signal Detection Theory (SDT) approach to olive oil tasting research within laboratory conditions akin to ecological tasting situations. Participants confronted a tasting situation in which olive oil concentration (0.4%, 0.8% or 1.6%) and instructions (lenient or conservative) were manipulated in a full factorial between-subjects design. Results were analyzed using a variety of measures of sensitivity and bias, both parametric and non-parametric, as well as robust statistics. Olive oil concentration only affected sensory processes while instructions only affected decision processes. Non-parametric indices of sensitivity A′ and bias B′D, and robust analysis of variance were, both conceptually and methodologically, the most suitable for separately measuring sensory and decision processes in the context of olive oil tasting. [Copyright &y& Elsevier]

Abstract: Training schedules including progressive increments of difficulty lead to a better performance on a harder version of a discrimination task than non-progressive schedules that only include the hardest level of difficulty. A detection task in which participants had to detect whether the samples that they tasted contained a small amount of olive oil was used to test the relevance of this phenomenon in an olive oil tasting context. Two groups of participants received three training sessions with this task before receiving a final test of performance. In group hard-to-hard, olive oil concentration was kept low and constant throughout sessions and testing. In group easy-to-hard, olive oil concentration was high in the first training session. Olive oil concentration was progressively decreased across sessions, reaching the same level of the hard-to-hard group at the time of testing. Results showed better ability for detecting olive oil when participants were trained with progressively lower concentrations of olive oil than when the training program involved only the lowest (most difficult) one. Progressive training led participants to show a conservative bias that did not appear when training was only conducted with the most difficult discrimination. [Copyright &y& Elsevier]

Human participants were trained in a trial-by-trial contingency judgements task in which they had to predict the probability of an outcome (diarrhoea) following different cues (food names) in different contexts (restaurants). Cue P was paired with the outcome on half of the trials (partial reinforcement), while cue C was paired with the outcome on all the trials (continuous reinforcement), both cues in Context A. Test was conducted in both Context A and a different but equally familiar context (B). Context change decreased judgements to C, but not to P (Experiment 1). This effect was found only in the cue trained in the context where a different cue was partially reinforced (Experiment 2). Context switch effects disappeared when different cues received partial reinforcement in both contexts of training (Experiment 3). The implications of these results for an explanation of context switch effects in terms of ambiguity in the meaning of the cues prompting attention to the context (e.g., Bouton, 1997) are discussed. [ABSTRACT FROM AUTHOR]

Experimental research in Psychology is characterized by ensuring a method that guarantees objectivity, reliability, validity and replication of results. In this theoretical study we propose a set of criteria for the preparation and review of quasi-experimental and experimental research manuscripts, which follows such methodological objective dictates. These criteria are based on a review of structural aspects in experimental research, in the modern theory of psychological theorization, and in the validity theory of scientific research. All these aspects are complemented with those proposed in revisions about empirically-based, statistically-based peer-review systems, and recently refined according to the expert judgment approach. We distinguish between essential, obligatory, complementary, and methodological criteria. These norms are organized according to a measuring tool -the ExperimenCheck2 system-, including report characteristics, antecedents, theoretical development, design, analysis and interpretation of results, format and bibliographical sources, also summarized in the form of a conceptual map. We also introduce the general guidelines of a reviewing process that fulfils scientific criteria, using the proposed evaluative guideline as the main organizing principle. [ABSTRACT FROM AUTHOR]

The role of context in retrieval of the information is explored, focusing in the differential effects of context change on acquisition and interfering information. Retrieval theory has proposed that context changes affect a specific type of information, either inhibitory or second-learned, interfering information. We propose a modification of retrieval theory based on recent results in our laboratory that suggests that context-specificity does not depend on specific features of the information, but on specific features of the situation that lead participants to pay attention to the context. Once there is something in the situation that leads participants to pay attention to the context, all the information learned seems to become context specific, regardless of whether it is the first or the second meaning of the cue. The outlines of this attentional theory of context processing are proposed. [ABSTRACT FROM AUTHOR]

• Context change impairs expression of acquisition in the absence of interference. • Switching the context reduces predictive ratings and response speed. • Experiencing interference enhances the effect of changing the context on acquisition. • The Extinction Makes Acquisition Context Specific effect is demonstrated using images rather than verbally defined contexts. One experiment evaluated the effect of extinction on the context dependence of non-extinguished information in a situation in which physical (images), rather than predominantly verbal, contexts were used in human predictive learning. Participants received training in which different foods (Cues) were associated with the presence or the absence of gastric illness (outcome) in customers of different restaurants (contexts). One cue was associated with the gastric illness while a different cue was either extinguished or not between groups. A change in the context at test led to a general decrease in both predictive judgments and the speed of responding to the non-extinguished cue. However, these decreases were greater when training was conducted during extinction of the different cue demonstrating the extinction makes acquisition context-specific (EMACS) effect. Results are contrasted with failures to find the effect in other reports and discussed in terms of extinction leading to an allocation of attentional resources to the context, facilitating the context dependence of information. [ABSTRACT FROM AUTHOR]

Abstract: Sensory evaluation of olive oil has been conducted by using the Classical Threshold Theory perspective. This approach does not allow the separation of purely sensory processes from other factors that may affect performance such as tasters’ cognitive biases. Two experiments were conducted with the goal of developing a task that, using the logic of Signal Detection Theory (SDT), would allow sensory and decision processes to be separately assessed within an olive oil tasting task, overcoming the shortcomings of the traditional Classical Threshold Theory approach. Experiment 1a used classic psychophysics theory to establish the olive oil concentrations that were used later in Experiment 1b. Experiment 1b presents a taste task based on SDT (by using signal and noise stimuli) that allowed establishing ROC curves and the separate calculation of sensory and decision indexes. Non-parametric detection and sensory indexes, and robust analyses of variance are proposed to overcome the problems associated with the use of a limited number of trials involved. The advantages of the SDT approach in olive oil tasting are discussed. [Copyright &y& Elsevier]

The extinction of learned fear is a hippocampus-dependent process thought to embody new learning rather than erasure of the original fear memory, although it is unknown how these competing contextual memories are represented in the hippocampus. We previously demonstrated that contextual fear conditioning results in hippocampal place cell remapping and long-term stabilization of novel representations. Here we report that extinction learning also induces place cell remapping in C57BL/6 mice. Specifically, we observed cells that preferentially remapped during different stages of learning. While some cells remapped in both fear conditioning and extinction, others responded predominantly during extinction, which may serve to modify previous representations as well as encode new safe associations. Additionally, we found cells that remapped primarily during fear conditioning, which could facilitate reacquisition of the original fear association. Moreover, we also observed cells that were stable throughout learning, which may serve to encode the static aspects of the environment. The short-term remapping observed during extinction was not found in animals that did not undergo fear conditioning, or when extinction was conducted outside of the conditioning context. Finally, conditioning and extinction produced an increase in spike phase locking to the theta and gamma frequencies. However, the degree of remapping seen during conditioning and extinction only correlated with gamma synchronization. Our results suggest that the extinction learning is a complex process that involves both modification of pre-existing memories and formation of new ones, and these traces coexist within the same hippocampal representation., (Copyright © 2015 the authors 0270-6474/15/359122-15$15.00/0.)

Fear is an emotional response to danger that is highly conserved throughout evolution because it is critical for survival. Accordingly, episodic memory for fearful locations is widely studied using contextual fear conditioning, a hippocampus-dependent task (Kim and Fanselow, 1992; Phillips and LeDoux, 1992). The hippocampus has been implicated in episodic emotional memory and is thought to integrate emotional stimuli within a spatial framework. Physiological evidence supporting the role of the hippocampus in contextual fear indicates that pyramidal cells in this region, which fire in specific locations as an animal moves through an environment, shift their preferred firing locations shortly after the presentation of an aversive stimulus (Moita et al., 2004). However, the long-term physiological mechanisms through which emotional memories are encoded by the hippocampus are unknown. Here we show that during and directly after a fearful experience, new hippocampal representations are established and persist in the long term. We recorded from the same place cells in mouse hippocampal area CA1 over several days during predator odor contextual fear conditioning and found that a subset of cells changed their preferred firing locations in response to the fearful stimulus. Furthermore, the newly formed representations of the fearful context stabilized in the long term. Our results demonstrate that place cells respond to the presence of an aversive stimulus, modify their firing patterns during emotional learning, and stabilize a long-term spatial representation in response to a fearful encounter. The persistent nature of these representations may contribute to the enduring quality of emotional memories.