Decision theory,reinforcement learning,and the brain

Decision making is a core competence for animals and humans acting and surviving in environments they only partially comprehend, gaining rewards and punishments for their troubles. Decision-theoretic concepts permeate experiments and computational models in ethology, psychology, and neuroscience. Here, we review a well-known, coherent Bayesian approach to decision making, showing how it unifies issues in Markovian decision problems, signal detection psychophysics, sequential sampling, and optimal exploration and discuss paradigmatic psychological and neural examples of each problem. We discuss computational issues concerning what subjects know about their task and how ambitious they are in seeking optimal solutions; we address algorithmic topics concerning model-based and model-free methods for making choices; and we highlight key aspects of the neural implementation of decision making.     

Perceptions of ADHD Among Diagnosed Children and Their Parents: A Systematic Review Using the Common-Sense Model of Illness Representations

Research on children and parents’ experiences of ADHD has grown in recent years, attracting attention to their subjective perception of ADHD as a disorder. Theoretical accounts of illness perception suggest that it is multi-dimensional, consisting of at least five core constructs (see the common-sense model of illness representations or CSM: Leventhal et al., in: Rachman (ed) Medical psychology, Pergamon, New York, vol 2, pp 7–30, 1980, in: Baum, Taylor, Singer (eds) Handbook of psychology and health: social psychological aspects of health, Earlbaum, Hillsdale, vol 4, pp 219–252, 1984). We suggest that the application of CSM in children/adolescents with ADHD and their parents may play an important role in understanding their coping behavior, treatment adherence, and emotional well-being. A systematic search identified 101 eligible studies that investigated the perception of ADHD among diagnosed children/adolescents and their parents. In general, these studies support the existence of the multiple facets of illness representations proposed by the CSM in both diagnosed youngsters and parents indicating substantial variability among both parents and youngsters on each of these facets. The comprehensive assessment of the representations of ADHD indicates imbalance attention to the different representations of ADHD in the literature; disproportional research attention has been paid to the perceived effectiveness of treatment (i.e., treatment control dimension) compared to other illness representations (e.g., timeline, consequence, and coherence), despite research showing their relevance to treatment adherence among other implications. The review identifies the limitation of existing relevant research, needed foci for future studies, specific testable hypotheses, and potential clinical implications of the multifaceted representations of ADHD among youngsters and carers alike.     

Body asymmetry affects conjugate lateral eye movement

A. H. Baker (1989) and A. H. Baker and A. I. Ledner (1990) reported that asymmetrical visual stimulation affects conjugate lateral eye movement (CLEM). In the present article, the authors explored whether asymmetrical body position similarly affects CLEM. The authors assessed CLEMs twice in a counterbalanced design. In the control (symmetric) condition, each participant sat in a completely symmetrical position facing a wall devoid of any asymmetrical features. In the experimental (asymmetrical) condition, half the participants rotated their heads 68 degrees clockwise relative to their bodies to face the experimenter, and the other half rotated their heads 68 degrees counterclockwise, also to face the experimenter. CLEM was predominantly toward the body's position in the asymmetrical condition rather than toward the body's position in the symmetrical condition.     

The same but different: an empirical investigation of the reducibility principle

According to classical utility theory the valuation of any lottery should depend only on its outcomes and their respective probabilities, and should not be affected by the nature, complexity and structure of the chance mechanism. Previous research has documented systematic violations of this principle. For example, most subjects prefer lotteries in which the payoffs are contingent on the joint occurrence of multiple (high probability) events to simple lotteries, and lotteries in which the earlier stages offer higher probabilities than the later stages. We review the various violations of this principle and suggest a classification into two major types associated with misunderstanding of chance mechanisms and attitude towards the chance mechanism and process. In the present study 40 subjects were presented with 30 pairs of binary gambles. In any given pair the lotteries had identical outcomes and equal ‘reduced’ probabilities (and thus equal expected values). However, the chance mechanisms varied along a variety of factors such as the size of the sample space, the number of stages, temporal ordering, order of probabilities, their transparency and time constraints. Half the subjects saw lotteries involving gains and the other half considered only losses. After choosing one lottery in each pair, the subjects were asked to explain and justify their choices. The findings revealed systematic violations of the reducibility principle: subjects displayed a preference for lotteries with larger sample spaces, and for lotteries that allow quicker resolutions in the earlier stages. A clear distinction between some patterns of preferences in the gains and loss domains was revealed. In gambles involving gains subjects preferred to have the highest probability on the first stage (and the lowest probability on the last stage), but displayed the opposite preferences for losses. A content analysis of the subjects' stated reasons for their choices identified eight major categories. The most frequently invoked were hope, fun, simplicity, stress and time. Copyright © 2001 John Wiley & Sons, Ltd.     

Autobiographical Memory, Self, and Stress-Related Psychiatric Disorders: Which Implications in Cancer Patients?

Autobiographical memory refers to information and memories of personal life events, accumulated since childhood, which enable the construction of a feeling of identity and continuity. Autobiographical memory retrieval is a dynamic and reconstructive process, as mental representations change with the passage of time. This flexible aspect of memory is linked to one’s changing self and aspirations over time, that evolve according to our personal status and environment. Hence, any breakdown in the continuity of life involves a distortion of memory. Such distortions can be observed in stress-related psychiatric disorders, such as major depression or post-traumatic stress disorder, where autobiographical memory retrieval is characterized by overgenerality (i.e., the tendency to recall generic memories rather than specific events in response to cue words). Such memory disorders can be observed at different degrees in cancer patients. We will report studies focusing on the above-mentioned psychiatric disorders and cancer, and will attempt to establish a relation with autobiographical memory disturbances. The better understanding of such memory deficits could permit new pathophysiological hypotheses to emerge. Recommendations for future research that will enhance understanding of the factors that contribute to autobiographical memory in cancer are suggested.     

Must coping options be severely limited during stressful events: Testing the interaction between primary and secondary appraisals

Abstract

It is assumed that psychological stress develops in personally relevant events when situational demands tax or exceed coping resources (i.e., when coping options are severely limited). Despite the central role of this proposition in defining stress, it has been little investigated due to conceptual overlap in definitions of primary and secondary appraisals. In the present work, the interaction between primary and secondary appraisals was used in order to test this proposition, employing non-overlapping definitions of appraisal components. Appraisals were manipulated independently, using written scenarios of stressful occupational episodes, each with three levels of personal stakes and three levels of coping options. Results indicated that the appraisal factors exerted main, but not interaction, effects on negative and positive moods. This means that emotional response increases in proportion to the level of personal stakes in the encounter, with coping potential acting as independent predictor, rather than moderator variable. Contrary to expectations, therefore, emotional distress might develop under conditions where situational demands fall short of exerting all the available resources for coping. The theoretical implications of these results are discussed.     

Effects of Adult Attachment Style on the Perception and Search for Social Support

Effects of adult attachment style on the perception of and search for social support were examined. One hundred and fifty undergraduate students completed self-report scales tapping their attachment styles, the extent to which they perceive the availability of emotional and instrumental support from significant figures (father, mother, same-sex friend, opposite-sex friend, romantic partner), and the extent to which they look for instrumental and emotional assistance in times of need. Findings showed that secure persons perceived higher levels of emotional and instrumental support from the assessed figures and reported seeking more emotional and instrumental support than avoidant and ambivalent persons did. Results are discussed in the context of an attachment perspective of social support.     

“Anxious” and “reckless” drivers

This paper presents personality profiles of two types of recidivist traffic offenders. One is the “anxious” traffic offender who imputes legitimacy to traffic norms, yet due to innate structural personality defects, he tends to enter into a state of anxiety, when confronted with risky traffic situations or a traffic jam. The other type is the “reckless” driver, who does not impute legitimacy to traffic norms nor to other legal norms. From this personality theory a number of hypotheses were derived and tested by means of multiple regression. Our ability to predict the number of traffic offenses suggests that similar tools may be used by the traffic authorities and traffic courts.