Categories and Dimensions

ABSTRACT— The distinction between categories and dimensions has important consequences for basic and applied science in many areas of psychological research. Decisions as to whether individuals should be assigned to groups or located along one or more continua often are based on personal preferences or discipline-specific measurement traditions, which can lead to the creation, use, or reification of spurious categories or dimensions. Methods for evaluating the latent structure of psychological constructs, using powerful and informative tests between competing models, are available. Rather than choosing on a priori grounds, investigators can perform structural research to evaluate the strength and consistency with which results tease apart categorical and dimensional models. Here, we review why researchers should make this distinction empirically, briefly discuss methods available for doing so, and describe the breadth of areas ripe for exploiting the largely untapped potential of structural research.     

The dilution model: how additional goals undermine the perceived instrumentality of a shared path

Six experiments tested a dilution model of self-regulation, whereby increasing the number of goals (e.g., building muscles and losing weight) that a single means (e.g., exercising) can satisfy reduces the perception of its instrumentality with respect to each goal. The authors found that an increase in the number of simultaneous, salient goals that can be satisfied via a single means weakens the associative strength between that means and each individual goal, and as a result, individuals perceive the means as less effective for the attainment of each goal. Consequently, means that are connected to multiple (vs. single) goals are less likely to be chosen and pursued when only one of these goals is activated.     

Be better or be merry: how mood affects self-control

In 6 studies, the authors tested whether the effect of mood on self-control success depends on a person's accessible goal. We propose that positive mood signals a person to adopt an accessible goal, whereas negative mood signals a person to reject an accessible goal; therefore, if a self-improvement goal is accessible, happy (vs. neutral or unhappy) people perform better on self-control tasks that further that goal. Conversely, if a mood management goal is accessible, happy people abstain from self-control tasks because the tasks are incompatible with this goal. This pattern receives consistent support across several self-control tasks, including donating to charity, demonstrating physical endurance, seeking negative feedback, and completing tests.     

Event-based prospective memory for poorly attended events

In the most frequently used paradigm for studying event-based prospective memory (PM, Einstein & McDaniel, 1990), participants perform an ongoing task and are asked to perform an additional task when a particular stimulus (the PM cue) is presented. In this study three experiments examined how PM performance depends on stimulus selection, which is a major process involved in executive task control according to current theorizing. Participants made semantic judgments about a target word accompanied by two nontargets (distracters). The target was indicated by its spatial position (Experiment 1) or color (Experiment 2). The findings indicated that PM performance was much poorer when the PM cue was irrelevant to the ongoing task, in spite of the fact that nontargets were processed semantically as shown in Experiment 3.     

Experience and appraisal of worry among high worriers with and without generalized anxiety disorder

Recent research has revealed that a large number of highly worried individuals do not qualify for a diagnosis of generalized anxiety disorder (GAD). This raises the intriguing question of why some high worriers are more impaired and distressed by their worrying than others, particularly when the severity of their worry is the same. The present investigation sought to address this question by examining whether GAD and non-GAD high worriers differ in their actual worry experiences, their subjective appraisals of worry experiences, or both experiences and appraisals of worry. GAD and non-GAD worriers, selected for matching levels of trait worry severity, completed an attention-focus task with thought sampling before and after a brief worry induction. They also completed questionnaires assessing their experiences during and after the worry induction, as well as their general beliefs about worry. GAD worriers experienced less control over negative intrusive thoughts immediately after worrying, reported greater somatic hyperarousal following worry, and endorsed several negative beliefs about worry more strongly than their worry-matched controls. Results suggest that GAD is associated with unique experiences and appraisals that distinguish it from other forms of severe worry.     

Two-year-olds' sensitivity to speakers' intent: an alternative account of Samuelson and Smith

Seventy-two 2-year-olds participated in a study designed to test two competing accounts of the effect of contextual change on children's ability to learn a word for an object. The mechanistic account hypothesizes that any change in context that highlights a target object will lead to word learning; the social-pragmatic account maintains that a change in context must be perceived as relevant to the speaker's communicative intentions. Consistent with the latter account, we found that children learned the word when a change in context was intentional but not when it was accidental, and children failed to learn the word for the highlighted object when a speaker naive to the preceding context named the object.     

Traditionality of children's interests as related to their parents' gender stereotypes and traditionality of occupations

This study tested the common hypothesis that parents' gender stereotypes, maternal employment status, and the traditionality of parents' occupations, are associated with the traditionality of children's vocational interests. The traditionality of preschool children's (n=113) interests was examined by an instrument developed for the current study. Parents were administered the Attitudes toward Women Scale, and traditionality of their occupations was assessed. Only the traditionality of the mothers' occupations significantly correlated with the traditionality of the interests of both boys and girls. Other variables tested, as well as their interactions, were not found to show such relationships. The results were discussed in terms of the function of the role model in gender identity development and vocational schema modification.We thank Rachel Karniol for her helpful comments on an earlier draft of this article.     

Self-control in action: implicit dispositions toward goals and away from temptations

Five studies examined whether, in self-control dilemmas, individuals develop an implicit disposition to approach goals and avoid temptations, psychologically as well as physically. Using a method developed by A. K. Solarz (1960; see also K. L. Duckworth, J. A. Bargh, M. Garcia, & S. Chaiken, 2002), the authors assessed the time for pulling and pushing a lever in response to goal- and temptation-related stimuli (e.g., studying and partying). The results show that individuals offset the influence of tempting activities by automatically avoiding these stimuli (faster pushing responses) and by approaching stimuli related to an overarching goal (faster pulling responses). These implicit self-control dispositions varied as a function of the magnitude of the self-control conflict, itself defined by how strongly individuals were attracted to temptations and held the longer term goal. These dispositions were further shown to play a role in successful self-control.     

Mothers' insightfulness regarding their infants' internal experience: relations with maternal sensitivity and infant attachment

This study examined the associations among mothers' insightfulness into their infants' internal experience, mothers' sensitivity to their infants' signals, and infants' security of attachment to their mothers. The insightfulness of 129 mothers of 12-month-old infants was assessed by showing mothers 3 videotaped segments of observations of their infants and themselves and interviewing them regarding their infants' and their own thoughts and feelings. Interviews were classified into 1 insightful and 3 noninsightful categories. Mothers' sensitivity was assessed during play sessions at home and at the laboratory, and infant-mother attachment was assessed with the Strange Situation. Mothers classified as positively insightful were rated as more sensitive and were more likely to have securely attached children than were mothers not classified as positively insightful. Insightfulness also accounted for variance in attachment beyond the variance explained by maternal sensitivity. These findings add an important dimension to research on caregiving, suggesting that mothers' seeking of explanations for the motives underlying their infants' behavior is related to both maternal sensitivity and infant attachment.