Shifts of the psychometric function: Distinguishing bias from perceptual effects

Morgan, Dillenburger, Raphael, and Solomon have shown that observers can use different response strategies when unsure of their answer, and, thus, they can voluntarily shift the location of the psychometric function estimated with the method of single stimuli (MSS; sometimes also referred to as the single-interval, two-alternative method). They wondered whether MSS could distinguish response bias from a true perceptual effect that would also shift the location of the psychometric function. We demonstrate theoretically that the inability to distinguish response bias from perceptual effects is an inherent shortcoming of MSS, although a three-response format including also an “undecided” response option may solve the problem under restrictive assumptions whose validity cannot be tested with MSS data. We also show that a proper two-alternative forced-choice (2AFC) task with the three-response format is free of all these problems so that bias and perceptual effects can easily be separated out. The use of a three-response 2AFC format is essential to eliminate a confound (response bias) in studies of perceptual effects and, hence, to eliminate a threat to the internal validity of research in this area.     

The Effect of Variety and Dietary Restraint on Food Intake in Lean Young Women: A Preliminary Study

When satiety develops specific to sensory properties of food, variety leads to increased eating. The relationship between meal variety and dietary restraint was explored here in lean young women (18–20 years), classified into unrestrainers versus restrainers using the Dutch Eating Behavior Questionnaire Restrained Eating Scale. The expected variety effect obtained for unrestrainers (p < .05) but not for restrainers, despite a typical sensitivity to sensory-specific satiety and the same rate of habituation to sensory-based food responses (i.e., hedonics) across them. Unrestrainers’ eating appeared guided by hedonics (p < .05), but not restrainers’. These results suggest the potential involvement of an internal or participant characteristic, instead of an external factor, in moderating unrestrainers’ versus restrainers’ food consumption when offered a highly desired food (the favorite in the plain condition) versus less desired (but accepted) foods (presented successively with the favorite in the variety condition). Study limitations and suggestions for further research were discussed.     

Psychosocial correlates of bulimic symptomatology among male athletes

ObjectivesTo examine the relationship of four psychosocial constructs – body dissatisfaction, restrained eating, drive for muscularity, and negative affect – that have been identified as potential risk factors for bulimic symptoms in male athletes.DesignWe used a cross-sectional design and self-report questionnaires.MethodsParticipants were 203 male, NCAA Division I athletes who were drawn from three different U.S. universities and who competed in 17 different varsity sports. Athletes completed self-report measures of body satisfaction, dietary restraint, drive for muscularity (i.e., muscularity behaviors, muscular body image), negative affect (i.e., fear, hostility, guilt, sadness), and bulimic symptomatology.ResultsAfter controlling for the effects of body mass and social desirability, hierarchical regression analysis showed that the psychosocial variables explained an additional 21% of the variance in bulimic symptoms. In the full model, engaging in muscle building behaviors (β = .16), such as lifting weights, as well as restricting caloric intake (β = .33) were associated with higher levels of bulimic symptomatology; negative affect and body dissatisfaction were not.ConclusionsMale athletes' bulimic symptomatology is best explained by the extent to which they report engaging in behaviors to become leaner (i.e., less body fat) and more muscular.     

Amalia X: dialogical sequence analysis as a method in theory-based single case research in psychoanalysis

In this article, Dialogical sequence analysis (DSA) is introduced as a method in theory-based single case research. The structure of article is as follows: first, we will describe briefly the historical background of single case studies and their position as the foundation of psychoanalytic knowledge formation. Secondly, we will describe through Amalia X’s case how one psychoanalytic ‘specimen case’ has been used as a cornerstone for a comprehensive psychoanalytic process research model, the so called ‘Ulm model’. Amalia X is one of the most studied single cases internationally also outside psychoanalytic process study field. Thirdly, we will introduce the central theory and practice of DSA. Fourthly, in the last section of our article, we will show in practice how DSA can be used in the analysis of Amalia’s dream in the session 152.     

The impact of holiday eating cues on self-regulatory bolstering for dieters and non-dieters

Objective: Two studies examined the hypothesis that the presence vs. absence of holiday food cues leads dieters to bolster self-regulatory resources and reduce consumption of a snack food. Study 1 evaluated snack-food consumption on a holiday vs. a non-holiday and in Study 2, the proposed underlying mechanism – the bolstering of self-regulatory resources when facing holiday-related cues – was explored.

Methods: Study 1 followed a quasi-experimental design in which participants (N?=?152) consumed candies either on a holiday or a non-holiday. Dieting behaviour was measured and the main outcome measure was consumption quantity. In Study 2, a true experiment, participants (N?=?110) read primes associated with holiday eating, holiday history or a neutral topic. Self-regulatory bolstering was assessed as the main outcome measure.

Results: Study 1 showed that dieters consume more of a food item on an ordinary day relative to a holiday; the consumption patterns of non-dieters did not vary based on holiday cues. Study 2 demonstrated that dieters, but not non-dieters, bolster self-regulatory resources to a greater extent in the presence vs. absence of a holiday food cue.

Conclusion: Dieters are better equipped to defend their diet-related goals when facing strong holiday-related temptations than weaker, everyday temptations.     

The relationship between dietary restraint and deficits in reasoning about causes of obesity

Abstract

Objective: Increased levels of dietary restraint are associated with deficits on many cognitive tasks. Less is known about how individual differences in restraint influences complex cognition such as reasoning which is the focus of this research.

Design: Two experimental studies are reported. In study 1, participants (n?=?158) completed a causal conditional reasoning task with statements about weight-related and general causal relationships. Study 2 replicated and extended study 1. Participants (n?=?108) completed a causal conditional reasoning task focusing on behavioural causes of weight change or general statements.

Main outcome measure: Causal conditional reasoning task performance.

Results: In study 1, levels of dietary restraint were negatively associated with reasoning abilities for weight-related statements only. Study 2 replicated the negative association between dietary restraint and reasoning finding the effect in both weight-related, and general, causal judgements.

Conclusion: The novel findings show that individual differences in dietary restraint have a wider relationship with cognition than previously demonstrated. Results tentatively support theoretical explanations of a reduction in cognitive capacity, rather than differences in belief, explaining reasoning deficits. These findings open an interesting avenue for research and might have implications for effective decision making about personal health behaviours, such as food choice.