Computational approaches to the development of perceptual expertise

Dog experts, ornithologists, radiologists and other specialists are noted for their remarkable abilities at categorizing, identifying and recognizing objects within their domain of expertise. A complete understanding of the development of perceptual expertise requires a combination of thorough empirical research and carefully articulated computational theories that formalize specific hypotheses about the acquisition of expertise. A comprehensive computational theory of the development of perceptual expertise remains elusive, but we can look to existing computational models from the object-recognition, perceptual-categorization, automaticity and related literatures for possible starting points. Arguably, hypotheses about the development of perceptual expertise should first be explored within the context of existing computational models of visual object understanding before considering the creation of highly modularized adaptations for particular domains of perceptual expertise.     

The US-preexposure effect in lithium-induced flavor-aversion conditioning is a consequence of blocking by injection cues

In 2 experiments, rats received flavor-aversion conditioning in which the unconditioned stimulus (US) was an orally consumed solution of lithium chloride (LiCl). The resulting aversion was not attenuated by giving preexposure to injections of LiCl, although such preexposure did attenuate aversions established using injected LiCl as the US (Experiment 1). This outcome suggests that blocking by injection-related cues is responsible for the US-preexposure effect observed in this situation. Experiment 2 confirmed this interpretation by showing that presenting such cues (by giving an injection of saline) at the time that the LiCl was drunk resulted in an attenuation of conditioning in animals preexposed to injections of LiCl. The US-preexposure effect obtained in these experiments can be explained solely in terms of blocking by injection cues, although other mechanisms may contribute to the effect seen in other flavor-aversion paradigms.     

Genetic and environmental bases of childhood antisocial behavior: a multi-informant twin study

Genetic and environmental influences on childhood antisocial and aggressive behavior (ASB) during childhood were examined in 9- to 10-year-old twins, using a multi-informant approach. The sample (605 families of twins or triplets) was socioeconomically and ethnically diverse, representative of the culturally diverse urban population in Southern California. Measures of ASB included symptom counts for conduct disorder, ratings of aggression, delinquency, and psychopathic traits obtained through child self-reports, teacher, and caregiver ratings. Multivariate analysis revealed a common ASB factor across informants that was strongly heritable (heritability was .96), highlighting the importance of a broad, general measure obtained from multiple sources as a plausible construct for future investigations of specific genetic mechanisms in ASB. The best fitting multivariate model required informant-specific genetic, environmental, and rater effects for variation in observed ASB measures. The results suggest that parents, children, and teachers have only a partly "shared view" and that the additional factors that influence the "rater-specific" view of the child's antisocial behavior vary for different informants. This is the first study to demonstrate strong heritable effects on ASB in ethnically and economically diverse samples.     

Beyond egoism and group identity: empathy toward the other and awareness of others in a social dilemma

In three experiments, participants were faced with a social dilemma in which they could benefit themselves, the group, or other group members as individuals. The results showed that participants who felt high empathy toward a certain individual allocated more resources to the target of empathy, but without reducing the collective good. Then, we adapted the measure of empathy developed by Batson and colleagues (Batson, Ahmad, et al., 1999; Batson, Batson, et al., 1995) to the Spanish context. The results of Experiment 3 supported the existence of a new process: awareness of other individuals present in the social dilemma. It is proposed that this process is independent of those typically studied in research of this field: self-interest, group identification, and the empathy for a specific individual.     

Differential effects of emotional arousal in short- and long-term memory in healthy adults

Recent studies demonstrated important differences between short- and long-term memory mechanisms. Besides, the emotional component has a crucial role in memory formation. This study was carried out to answer whether there is a differential influence of emotional arousal in short- and long-term memory in healthy adults. Thirty-one healthy volunteers were divided into two major groups. In the first group long-term memory (LTM) was evaluated, with the testing session one week after training. The second group was tested 1h after training, where short-term memory (STM) was evaluated. Each group was divided in to two subgroups. One half of the volunteers was exposed to an emotionally neutral story, and the other half of each group was exposed to a closely matched but more emotionally arousing story. The testing session consisted of a questionary containing 80 questions of multiple choices. The results were evaluated through percentage of correct answers. Results showed that correct answers were increased, in LTM measures, in the subjects that were given the emotional version of the test. In STM measures, no differences were found between the emotional and neutral version. However, the presentation of emotional story caused an emotional reaction in both groups. The lack of effect of emotional arousal in STM suggests that amygdala is not related to STM mechanisms. Further studies using different approaches are needed to elucidate if STM processes are influenced by emotional arousal.     

Pigeons use item-specific and category-level information in the identification and categorization of human faces

Three experiments examined the pigeon's ability to adapt to the specific tasks of identification and categorization of complex visual stimuli by attending to information at different levels of abstraction. In Experiment 1, pigeons were successively trained to discriminate first between pairs of human faces from the same sex and then between male and female faces. A final test revealed that the associations formed in the first training phase did not survive categorization training, indicating that the pigeons used item-specific information to discriminate faces of the same sex, but shifted their attention to category-level information for discriminating between the male and female categories. Two further experiments disproved alternative explanations. The results support the feature-learning account of open-ended categorization in animals.     

Does temporal integration of face parts reflect holistic processing?

We examined whether temporal integration of face parts reflects holistic processing or response interference. Participants learned to name two faces “Fred” and two “Bob.” At test, the top and bottom halves of different faces formed composites and were presented briefly separated in time. Replicating prior findings (Singer & Sheinberg, Vision Research, 46, 1838–1847, 2006), naming of the target half for aligned composites was slowed when the irrelevant half was from a face with a different name rather than from the original face. However, no interference was observed when the irrelevant half had a name identical to the name of the target half but came from a different learned face, arguing against a true holistic effect. Instead, response interference was obtained when the target half briefly preceded the irrelevant half. Experiment 2 confirmed a double dissociation of holistic processing versus response interference for intact faces versus temporally separated face halves, suggesting that simultaneous presentation of facial information is critical for holistic processing.     

Family Gender Role and Guilt in Spanish Dual-Earner Families

In dual-earner families the balance between work and family demands facilitates the development of guilt feelings when parents perceive a non-fulfillment of their responsibilities in childcare. Specifically, women who aspire to personal and professional development on the basis of more egalitarian gender role models must deal with the traditional stereotypes that maintain an intensive maternity mandate that prioritizes the family. On the other hand, for men the role change is primarily in the family setting with the development of a new father role more involved in the care of their children, which is not easily compatible with the more traditional breadwinner role. This study explored the feelings of guilt about parenting in 251 employed Spanish parents with children between 3 and 6 years of age, through the Scale of Guilt Feelings about Parenting, and its relationship with traditional stereotypes of maternal and family role. The scale addresses diverse situations pertaining to child rearing in which work requirements do not allow parents full availability for the care of their children. This availability is present in the model of intensive maternity and in the new father role model. Results indicate the presence of similar and high levels of guilt in fathers and mothers, although in men guilt is related to a non-traditional family role ideology, whereas in women guilt is related to a more traditional maternal role stereotype.     

Resource control and status as stimuli for arousing power motivation: An American-Chinese comparison

In this paper, we analyze power motivation from a cross-cultural perspective. Power motivation has been mainly studied within the Western culture. However, previous research suggests that some contours and nuances of power and power motivation may be culturally specific. In this article, we analyze cultural differences between American and Chinese students in how power motivation is aroused. Drawing from the cross-cultural literature, we propose that having decision-making control over resources increases levels of power motivation among Americans but not Chinese, whereas status-elevation increases power motivation among both Americans and Chinese. These hypotheses were tested experimentally with resource-control, status-elevation, and neutral conditions. The first hypothesis was fully supported, but the second one was only partially supported. Levels of power motivation in the neutral condition (i.e., dispositional power motives) were similar for American and Chinese participants, but power motivation arousal was greater for Americans than Chinese, in both power arousal conditions. These findings contribute to our understanding of the power motivation construct in a non-Western context.