Evaluating the reliance on past choices in adaptive learning models

Adaptive learning models are used to predict behavior in repeated choice tasks. Predictions can be based on previous payoffs or previous choices of the player. The current paper proposes a new method for evaluating the degree of reliance on past choices, called equal payoff series extraction (EPSE). Under this method a simulated player has the same exact choices as the player but receives equal constant payoffs from all of the alternatives. Success in predicting the next choice ahead for this simulated player therefore relies strictly on mimicry of previous choices of the actual player. This allows determining the marginal fit of predictions that are not based on the actual task payoffs. To evaluate the reliance on past choices under different models, an experiment was conducted in which 48 participants completed a three-alternative choice task in four task conditions. Two different learning rules were evaluated: an interference rule and a decay rule. The results showed that while the predictions of the decay rule relied more on past choices, only the reliance on past payoffs was associated with improved parameter generality. Moreover, we show that the Equal Payoff Series can be used as a criterion for optimizing parameters resulting in better parameter generalizability.     

The Brain can be Thought of as a Tool

In this paper I argue that the recent tendency to elevate neuropsychology to the status of the one true scientific core of studies of people thinking, feeling, acting and perceiving is not best understood as a simple mereological fallacy, that is the fallacy of ascribing certain properties of wholes to their parts, in particular mental concepts to the material brain as a part of a person. In defending Svend Brinkmann's way of undermining the claims of neuroscience against the criticism offered by Gaeto and Cornejo of the cognitive task-brain as tool proposal, I argue that a person's brain is part of the body of that person, but that the body is not a part of a person. Hence the use of person-concepts to describe brain activity is not a mereological fallacy. Rather human bodies are sites for people. Material tools can be fashioned or found at such sites. It is a fallacy to present neuroscience as the core of psychology but it is the error of deriving an `ought' from an 'is' as identified by David Hume. Where to look for a positive guide to a philosophically respectable psychology, that is a study program that does justice to the phenomena of human thinking, feeling, acting and perceiving, without falling into logical and semantic traps. I show how to adapt Aristotle's schema for 'complete explanation' to this role.     

Casa de Alba: Therapeutic community for severe mental health problems

The Romão de Sousa Foundation has worked for three years to establish Casa de Alba which aims to help individuals and families affected by mental health problems. Working within a relational-integrative framework, Casa de Alba has a multidisciplinary team which makes use of therapeutic community theory and a range of psychological therapies and psychosocial interventions including individual and group psychotherapy, occupational therapy, arts, yoga, psychiatric consultation and pharmacotherapy, as well as the encouragement of self-management in everyday activities within the house. The use of over 20 acres of outdoor space will form part of the day to day therapeutic programme with activities such as horticultural therapy, ridding, walking and sports. Supervision will be used to help the staff team integrate different modalities and approaches as well as to improve the service.     

Brain electrical activity from encoding to retrieval while maintaining and manipulating information in working memory

ABSTRACT

Differences between working memory maintenance (Mt) and manipulation (Mp) have been studied, mostly in the absence of stimuli (delay period); encoding and retrieval phases have been less explored. The present study assessed differences between Mt and Mp, by means of event-related potentials (ERPs) and event-related synchronisation (ERS) and desynchronisation (ERD) for theta, alpha and beta bands at: encoding, delay period and retrieval; using a delayed-match to sample task (DMST). Twenty-six young volunteers solved two DMST conditions (one for Mt and one for Mp). Higher behavioural accuracy for Mt than for Mp was observed. At encoding, higher amplitude for Mt at posterior regions to N1, P2 and P3 components were observed. In the delay period, differences in ERP components and frontal theta ERD were observed. Meanwhile, at retrieval, P3 amplitude and latency, as well as the theta band were modulated by both process (Mt or Mp) and type of trial (target or non-target stimuli). These findings mainly suggest different attentional implications at encoding, differences at the delay period related with task difficulty, and differential retrieval for Mt or Mp dependent on the process which the information comes from, suggesting that Mt and Mp differ at the very beginning of the processing.     

Losses Induce Consistency in Risk Taking Even Without Loss Aversion

It is posited that because of the attentional effect of losses, individuals would show more behavioral consistency in risk‐taking tasks with losses, even in the absence of loss aversion. In two studies, the consistency of risky choices across different experience‐based tasks was evaluated for gain, loss, and mixed (gain loss) tasks. In both studies, losses facilitated the consistency across tasks: the correlation between risk‐taking choices in different tasks increased when the tasks involved frequent losses. Study 2 also showed a positive effect of losses on temporal consistency. Losses increased the correlation between risk‐taking levels across two sessions that were 45 days apart. Also in Study 2, losses induced consistency between experiential risk‐taking choices and self‐reported ratings of risky behavior. In both studies, the positive effect of losses on consistency was observed even when the average participant did not exhibit loss aversion. Taken together, the results indicate that losses increase the consistency of risk‐taking behavior and suggest that this is due to the effect of losses on attention. Copyright © 2011 John Wiley & Sons, Ltd.     

Psychometric properties of the Spanish version of the Collective Efficacy Questionnaire for Sports

The present study analyses the psychometric properties of the Spanish version of the Collective Efficacy Questionnaire in Sports (CEQS). The sample comprises 312 athletes (167 males and 145 females), with a mean age of 24.09 (SD= 6.67), with diverse performance levels (professional, semiprofessional and university level), all practitioners of team sports. The factor structure of the questionnaire was analyzed with confirmatory factor analysis (CFA). The results confirm the 5-factor internal structure of the CESQ (Effort, Ability, Unity, Perseverance and Preparation), made up of four items each. We also found acceptable values of the alpha coefficient, which confirms that the CESQ is a reliable instrument. Lastly, we found preliminary support for the validity of the construct of the CESQ, which is sufficient evidence to justify its use to measure the collective efficacy in Spanish athletes.     

Loss aversion in the eye and in the heart: The autonomic nervous system's responses to losses

The common view in psychology and neuroscience is that losses loom larger than gains, leading to a negativity bias in behavioral responses and Autonomic Nervous System (ANS) activation. However, evidence has accumulated that in decisions under risk and uncertainty individuals often impart similar weights to negative and positive outcomes. We examine the role of the ANS in decisions under uncertainty, and its consistency with the behavioral responses. In three studies, we show that losses lead to heightened autonomic responses, compared to equivalent gains (as indicated by pupil dilation and increased heart rate) even in situations where the average decision maker exhibits no loss aversion. Moreover, in the studied tasks autonomic responses were not associated with risk taking propensities. These results are interpreted by the hypothesis that losses signal the subjective importance of global outcome patterns. Copyright © 2010 John Wiley & Sons, Ltd.     

Learning about faces: effects of trustworthiness on affective evaluation

The results of two studies on the relationship between evaluations of trustworthiness, valence and arousal of faces are reported. In Experiment 1, valence and trustworthiness judgments of faces were positively correlated, while arousal was negatively correlated with both trustworthiness and valence. In Experiment 2, learning about faces based on their emotional expression and the extent to which this learning is influenced by perceived trustworthiness was investigated. Neutral faces of different models differing in trustworthiness were repeatedly associated with happy or with angry expressions and the participants were asked to categorize each neutral face as belonging to a "friend" or to an "enemy" based on these associations. Four pairing conditions were defined in terms of the congruency between trustworthiness level and expression: Trustworthy-congruent, trustworthy-incongruent, untrustworthy-congruent and untrustworthy-incongruent. Categorization accuracy during the learning phase and face evaluation after learning were measured. During learning, participants learned to categorize with similar efficiency trustworthy and untrustworthy faces as friends or enemies and thus no effects of congruency were found. In the evaluation phase, faces of enemies were rated as more negative and arousing than those of friends, thus showing that learning was effective to change the affective value of the faces. However, faces of untrustworthy models were still judged on average more negative and arousing than those of trustworthy ones. In conclusion, although face trustworthiness did not influence learning of associations between faces and positive or negative social information it did have a significant influence on face evaluation that was manifest even after that learning.