Defining,measuring, and predicting impulsive aggression: a heuristic model

Aggression research does not lack data—it lacks a model for integrating data. One of the problems confronting aggression researchers is the extensive body of multidisciplinary data that is difficult to synthesize to generate new directions in research. This paper proposes one solution that starts by asking “what is the minimal number of categories of concepts and measurements which are necessary to describe a person?”. The answer is four categories of concepts: biological; cognitive; behavioral; environmental (physical and social). One way of many for integrating these four categories of concepts is a proposed discipline neutral heuristic model that is used herein to compare two different research approaches to the study of impulsive aggression. This comparison identifies clearly the differences in the two approaches with regard to different emphases among the four categories of constructs for each program. Using the model, an example of common ground between the two approaches is sought as a basis for extending aggression research. The main conclusion of one of the research programs was that central nervous arousal is related to impulsive aggression. This program demonstrated that phenytoin will reduce impulsive aggressive acts and has an effect on CNS arousal. The other research program on impulsive aggression has been at the forefront in demonstrating the well established inverse relationship between serotonin levels and aggression. The comparison resulted in the suggestion that both serotonin and phenytoin may relate to a common neurochemical substrate which interacts in part to control CNS arousal, especially at the cortical level. The proposed heuristic model made obvious the need to use synthesizing concepts (e.g. information processing or language) which can interrelate multidisciplinary concepts and data from different research programs within the four categories of constructs when comparing interdisciplinary research. This paper also discusses a two step procedure for classifying aggressive acts as impulsive or premeditated. © 1998 John Wiley & Sons, Ltd.     

Age-related changes in odor discrimination

Odor naming and recognition memory are poorer in children than in adults. This study explored whether such differences might result from poorer discriminative ability. Experiment 1 used an oddity test of discrimination with familiar odors on 6-year-olds, 11-year-olds, and adults. Six-year-olds were significantly poorer at discrimination relative to 11-year-olds and adults, who did not differ. Experiment 2 used the same procedure but with hard-to-name visual stimuli and compared only 6-year-olds with adults (as with the remaining experiments in this study). There was no difference in performance between these groups. Experiment 3 used the same procedure as Experiment 1 but with less familiar odors. Six-year-olds were significantly poorer at discrimination than adults. In Experiment 4 the researchers controlled for verbal labeling by using an articulatory suppression task, with the same basic procedure as in Experiment 1. Six-year-old performance was the same as for Experiment 1 and significantly poorer than that of adults. Impoverished olfactory discrimination may underpin performance deficits previously observed in children. These all may result from their lesser experience with odors, relative to adults.     

Binocular contrast interactions in two-frame motion discrimination

Previous studies have shown that two-frame motion detection thresholds are elevated if one frame's contrast is raised, despite the increase in average contrast--the "contrast paradox". In this study, we investigated if such contrast interactions occurred at a monocular or binocular site of visual processing. Two-frame motion direction discrimination thresholds were measured for motion frames that were presented binocularly, dichoptically or interocularly. Thresholds for each presentation condition were measured for motion frames that comprised either matched or unmatched contrasts. The results showed that contrast mechanisms producing the contrast paradox combine contrast signals from both eyes prior to motion computation. Furthermore, the results are consistent with the existence of monocular and binocular contrast gain control mechanisms that coexist either as combined or independent systems.     

Age-related changes in discrimination of unfamiliar odors

If odor perception involves mnemonic processes, differences in olfactory experience should affect discriminative ability. This was examined here by comparing discriminative performance in children and adults. Using an oddity test of discrimination, in Experiment 1 we tested 6-year-olds (G1), 11-year-olds (G6), and adults (A) on their ability to discriminate unfamiliar odors that varied either in quality (Q) or in quality and intensity (QI). G1 participants were poorer at discriminating the QI set, relative to G6 and A. In Experiment 2, we used an analogous visual procedure and confirmed that this age-related difference was olfactory specific. In Experiment 3, we repeated Experiment 1 but used an articulatory suppression task. G1 participants were poorer than G6 and A participants for both the Q and the QI sets. The implications of these findings for experiential accounts of odor perception and olfactory working memory are discussed.     

Muscle and fat aftereffects and the role of gender: Implications for body image disturbance

Body image disturbance – a cause of distress amongst the general population and those diagnosed with various disorders – is often attributed to the media’s unrealistic depiction of ideal bodies. These ideals are strongly gendered, leading to pronounced fat concern amongst females, and a male preoccupation with muscularity. Recent research suggests that visual aftereffects may be fundamental to the misperception of body fat and muscle mass – the perceptual component of body image disturbance. This study sought to establish the influence of gender on these body aftereffects. Male and female observers were randomly assigned to one of four adaptation conditions (low-fat, high-fat, low-muscle, and high-muscle bodies) and were asked to adjust the apparent fat and muscle levels of male and female bodies to make them appear as ‘normal’ as possible both before adaptation and after adaptation. While neither the gender of observers nor of body stimuli had a direct effect, aftereffect magnitude was significantly larger when observers viewed own-gender (compared with other-gender) stimuli. This effect, which may be due to attentional factors, could have implications for the development of body image disturbance, given the preponderance of idealized own-gender bodies in media marketed to male and female consumers.     

A social cure in the community: A mixed-method exploration of the role of social identity in the experiences and well-being of community volunteers

Cohesive, resilient communities are vital to the well-being of residents. Uncovering the determinants of successful community identities is therefore essential to progressing the community health agenda. Engaging in community participation through volunteering may be one pathway to building local community identity and enhancing residents’ health and well-being, but the group processes connecting them remain unexplored. We conducted two studies investigating these dynamics using the “Social Cure” perspective. First, we analysed 53 in-depth interviews with volunteers, finding that community relationships shaped their experiences and that volunteering influenced their sense of community belonging, support, and well-being. Second, a community survey (N = 619) revealed that volunteering predicts well-being through the serial mediators of community identification and social support. Our article demonstrates the Social Cure processes involved in community-based volunteering, their impact on community identity, support and well-being, and their implications for community health, and the provision and sustainability of community voluntary action and interventions.