Prototypes in category learning: the effects of category size, category structure, and stimulus complexity

Although research in categorization has sometimes been motivated by prototype theory, recent studies have favored exemplar theory. However, some of these studies focused on small, poorly differentiated categories composed of simple, 4-dimensional stimuli. Some analyzed the aggregate data of entire groups. Some compared powerful multiplicative exemplar models to less powerful additive prototype models. Here, comparable prototype and exemplar models were fit to individual-participant data in 4 experiments that sampled category sets varying in size, level of category structure, and stimulus complexity (dimensionality). The prototype model always fit the observed data better than the exemplar model did. Prototype-based processes seemed especially relevant when participants learned categories that were larger or contained more complex stimuli.     

Journey to the center of the category: the dissociation in amnesia between categorization and recognition

The authors' theoretical analysis of the dissociation in amnesia between categorization and recognition suggests these conclusions: (a) Comparing to-be-categorized items to a category center or prototype produces strong prototype advantages and steep typicality gradients, whereas comparing to-be-categorized items to the training exemplars that surround the prototype produces weak prototype advantages and flat typicality gradients; (b) participants often show the former pattern, suggesting their use of prototypes; (c) exemplar models account poorly for these categorization data, but prototype models account well for them; and (d) the recognition data suggest that controls use a single-comparison exemplar-memorization process more powerfully than amnesics. By pairing categorization based in prototypes with recognition based in exemplar memorization, the authors support and extend other recent accounts of cognitive performance that intermix prototypes and exemplars, and the authors reinforce traditional interpretations of the categorization-recognition dissociation in amnesia.     

Attachment and the management of empathic accuracy in relationship-threatening situations

The current studies tested how attachment orientations are related to empathic accuracy (i.e., the accuracy with which one infers a partner's private thoughts and feelings) during attachment-relevant discussions. In Study 1, married couples were videotaped discussing a severe or a less severe relationship issue that involved intimacy or jealousy. In Study 2, dating couples were videotaped trying to resolve a relationship conflict. Consistent with the revised empathic accuracy model, highly avoidant individuals were less empathically accurate in both studies. Relative to less anxious persons, highly anxious individuals were more empathically accurate when discussing intimacy issues that posed a potential threat to their relationship (in Study 1) and when they were rated as more distressed when discussing a relationship conflict (in Study 2). The findings are discussed in terms of how highly anxious and highly avoidant people differentially manage empathic accuracy to regulate negative affect and facilitate their interpersonal goals.     

Us without them: evidence for an intragroup origin of positive in-group regard

Four experiments examined whether group formation and positive in-group regard require interaggregate comparison as the in-group-requires-an-out-group assumption of the metacontrast principle implies. The authors fostered novel social aggregates with or without a contrasting aggregate with which members could compare and varied intra-aggregate factors (interaction or interdependence). Regardless of whether interaggregate comparison was feasible, the intra-aggregate factors increased the perceived entitativity of the aggregate and positive regard toward the aggregate (i.e., social attraction and cooperation among members). Mediation analyses were consistent with the possibility that the intra-aggregate factors promoted entitativity, which in turn promoted in-group regard. These data suggest that group formation and in-group regard have intragroup origins and do not require comparison with a contrasting social aggregate.     

Strategies of influence in close relationships

In this study, we examined how close relationship partners spontaneously influence each other while they discussed an existing problem in their relationship. According to theories of social influence, people in important, self-defining relationships should experience the relationship itself as a potent source of influence. Thus, they are likely to rely on the relationship as a source of power and to use influence strategies that reference relationship norms and values. Consistent with this reasoning, dating partners who were subjectively closer to their partners/relationships were more likely to reference the relationship in their influence attempts than those who were less subjectively close. Furthermore, referencing the relationship was an effective influence strategy. Greater referencing was associated with opinion shifts during discussions for both agents and targets of influence, with each compromising toward the other's position. In contrast, greater use of negative coercion as an influence strategy (e.g., derogation of the partner or punishment) was associated with less compromise.     

The effects of concurrent verbal and visual tasks on category learning

Current theories of category learning posit separate verbal and nonverbal learning systems. Past research suggests that the verbal system relies on verbal working memory and executive functioning and learns rule-defined categories; the nonverbal system does not rely on verbal working memory and learns non-rule-defined categories (E. M. Waldron & F. G. Ashby, 2001; D. Zeithamova & W. T. Maddox, 2006). However, relatively little research has explored the importance of visual working memory or visual processing for either system. The authors investigated the role of working memory (Experiment 1a and 1b), visual processing (Experiment 2), and executive functioning for each system, using a concurrent task methodology. It was found that visual tasks with high executive functioning demands and verbal tasks with high or low executive demands disrupted rule-defined learning, whereas any visual task, regardless of executive functioning demand, disrupted non-rule-defined learning. Taken together, these results confirm the importance of verbal working memory and executive functioning for the verbal system and provide new evidence for the importance of visual processing for the nonverbal system. These results help to clarify understanding of the nonverbal system and have implications for multiple systems theories of category learning (F. G. Ashby, L. A. Alfonso-Reese, A. U. Turken, & E. M. Waldron, 1998).     

Working models of attachment and reactions to different forms of caregiving from romantic partners

Inspired by attachment theory, the authors tested a series of theoretically derived predictions about connections between attachment working models (attachment to one's parents assessed by the Adult Attachment Interview; M. Main & R. Goldwyn, 1994) and the effectiveness of specific types of caregiving spontaneously displayed by dating partners during a stressful conflict-resolution discussion. Each partner first completed the Adult Attachment Interview. One week later, each couple was videotaped while they tried to resolve a current problem in their relationship. Trained observers then rated each interaction for the degree to which (a) emotional, instrumental, and physical caregiving behaviors were displayed; (b) care recipients appeared calmed by their partners' caregiving attempts; and (c) each partner appeared distressed during the discussion. Individuals who had more secure representations of their parents were rated as being more calmed if/when their partners provided greater emotional care, especially if they were rated as more distressed. Conversely, individuals who had more insecure (dismissive) representations of their parents reacted more favorably to instrumental caregiving behaviors from their partners, especially if they were more distressed. The broader theoretical implications of these findings are discussed.     

Correlation between clinical and paraclinical findings in brain tumors in comparison with the operation site

On the basis of clinical material consisting of 147 brain tumors, the authors carry out a comparative investigation involving the site of the ensuing operation to ascertain the accuracy of the clinical and paraclinical diagnoses. Computed tomographic findings were deliberately excluded with the intention of focusing on the accuracy attainable by traditional means. Clinical findings, X-ray examination of the skull, ophthalmological findings, electroencephalographic and echoencephalographic data, nuclear diagnosis, and angiographic findings were all taken into account.     

Category learning in rhesus monkeys: a study of the Shepard, Hovland, and Jenkins (1961) tasks

In influential research, R. N. Shepard, C. I. Hovland, and H. M. Jenkins (1961) surveyed humans' categorization abilities using tasks based in rules, exclusive-or (XOR) relations, and exemplar memorization. Humans' performance was poorly predicted by cue-conditioning or stimulus-generalization theories, causing Shepard et al. to describe it in terms of hypothesis selection and rule application that were possibly supported by verbal mediation. The authors of the current article surveyed monkeys' categorization abilities similarly. Monkeys, like humans, found category tasks with a single relevant dimension the easiest and perceptually chaotic tasks requiring exemplar memorization the most difficult. Monkeys, unlike humans, found tasks based in XOR relations very difficult. The authors discuss the character and basis of the species difference in categorization and consider whether monkeys are the generalization-based cognitive system that humans are not.     

Implications of Learning Style,Age Group,and Gender for Developing Online Learning Activities

ABSTRACT

This study explores the effects of learning style, age and gender on preferences for online educational activities. David Kolb's Experiential Learning Theory (Kolb, 1984 Kolb, D. A. 1984. Experiential learning: Experience as the source of learning and development, Englewood Cliffs, NJ: Prentice-Hall.  [Google Scholar]) is used as a lens to examine the responses of online learners to five types of educational activities. Results indicate that learning style influences preference for learning activity. The relationship is stronger among adults than among children aged 10–13 (middle school). The four learning styles were not evenly distributed. “Practical” (likes to solve problems and find solutions) was the most frequent style among both children and adults (37%). “Creative” (enjoys brainstorming and open-ended exploration) was the least frequent (8%). These data have particular relevance to the development of educational activities, suggesting that open-ended exploration with “no right answers” may not be the most satisfying and appealing approach for many learners. The results of this study provide new insight into online audiences and can help developers of multimedia activities to create experiences that will appeal to all kinds of learners.