Effects of Playing Videogames on Children's Aggressive and Other Behaviors1

Noting the pervasiveness of videogames in American culture, the authors set out to examine the effects that playing videogames has on children. Thirty-one children were matched on sex, randomly assigned to play either a violent (karate) videogame or a nonviolent (jungle vine swinging) videogame, and then observed during free play. The main results were that the children who had played the jungle swing videogame later played more with a jungle swing toy and that the children who played the violent videogame later showed more aggression. The authors interpreted the findings as an indication that young children who play videogames later tend to act similarly to how their videogame character acted.     

Denial and Confirmatory Search: Paradoxical Consequences of Medical Diagnosis1

An experiment was conducted to examine the effects of medical diagnostic-test results on illness appraisal and the recall of symptoms and behavior. Subjects were tested for a fictitious enzyme deficiency and were told either that the test result was positive (deficiency present) or that it was negative (deficiency absent). In addition, some of the subjects were told the test was accurate 95% of the time and others were told it was accurate 75% of the time. As predicted, subjects judged the enzyme deficiency as less serious and more prevalent when presented with positive test results. Subjects with positive test results also recalled more behaviors that had been labeled as risk factors. Although positive test subjects tended to report more deficiency-related symptoms, diagnosis did not affect the free recall of general symptoms. In addition, information concerning the reliability of the diagnostic test had no effect on judgments or recall but did affect information seeking. Subjects with positive test results were less likely to request a definitive follow-up test when their results were unreliable. The results are interpreted as evidence for independent confirmatory search and denial processes following medical diagnosis.     

Disarmament Decisions as Social Dilemmas1

The individual deciding on a nuclear weapons production policy is faced with a dilemma in which a choice must be made to support one of several conflicting defense policies. In order to investigate the social-psychological variables that are related to armament policy decision making, a telephone survey was conducted in the City of St. Louis, Missouri. Adult subjects (N= 110) responded to questions concerned with cognitive, attitudinal, and emotional responses to nuclear arms. Participants were also asked to choose a weapons production policy for the United States under conditions of continued and decreased Soviet nuclear arms production. Results indicated that respondents decisions about nuclear weapons production were related to their support for deterrence, the availability of their nuclear-related images, their emotional response to nuclear war, their attributions of responsibility for the prevention of nuclear war, and their political party affiliation. Distinctions between antinuclear decision-makers and pronuclear decision-makers are discussed.     

Neuroticism, extraversion, and related traits in adult twins reared apart and reared together

The relative importance of genetic and environmental factors for neuroticism, extraversion, impulsivity, and monotony avoidance were estimated in a sample of 99 monozygotic and 229 dizygotic pairs of twins reared apart (TRA) and a matched sample of 160 monozygotic and 212 dizygotic pairs of twins reared together (TRT). The average age was 58.6 (SD = 13.6); 72% of the twins were 50 or older. Model-fitting analyses verified the importance of genetic factors for all four measures; from 23% to 45% of the total variation was attributable to genetic sources. There was considerable evidence that these factors were operating in a nonadditive manner for extraversion and impulsivity. Shared environment accounted for less than 10% of the variance; some evidence for selective placement was found for neuroticism.     

Influence of positive affect on the subjective utility of gains and losses: it is just not worth the risk

A modification of the procedure originally used by Davidson, Suppes, and Siegel (1956) to measure subjective utility was used to study the influence of positive affect on individuals' perceived value (utility) functions. Results indicated, as expected, that persons in whom positive affect had been induced showed a more negative subjective utility for losses than did controls. This indicates that losses seem worse to people who are feeling happy than to those in a control condition. The subjective utility functions of the two groups did not differ as much, however, when people were considering potential gain. Thus, at least in the situation tested in this study, potential gains did not seem to be more appealing (nor less so) for affect subjects than they did for controls. These findings are discussed in relation to theoretical issues in decision making and work suggesting that positive affect can promote increased sensitivity to losses in situations of potential meaningful loss.     

Conceptions of states and traits: dimensional attributes with ideals as prototypes

Traits and states are concepts that people use to both describe and understand themselves and others. We show that people view these concepts as prototype-based categories that have a graded internal structure and fuzzy boundaries and identify a set of attributes that define the prototypical cores of two categories: traits and states. Prototypical traits are stable, long-lasting, and internally caused. Prototypical states are temporary, brief, and caused by external circumstances. These prototypes are not defined by averages, as the family-resemblance principle would suggest, but by ideal (or extreme) attribute values. Like other ideal-based categories, traits and states serve particular goals. Trait concepts permit people to predict the present from the past; state concepts identify those behaviors that can be controlled by manipulating the situation. These two complementary schemas are part of the extensive theory of psychological causality that is implicit in language. Abstract social concepts differ from object categories in their category standards, the nature of their attributes, and the interrelations among those attributes.     

The recognition of threatening facial stimuli

Two studies examined the information that defines a threatening facial display. The first study identified those facial characteristics that distinguish between representations of threatening and nonthreatening facial displays. Masks that presented either threatening or nonthreatening facial displays were obtained from a number of non-Western cultures and scored for the presence of those facial features that discriminated between such displays in the drawings of two American samples. Threatening masks contained a significantly higher number of these characteristics across all cultures examined. The second study determined whether the information provided by the facial display might be more primary nonrepresentational visual patterns than facial features with obvious denotative meaning (e.g., diagonal lines rather than downturned eyebrows). The subjective response to sets of diagonal, angular, and curvilinear visual stimuli revealed that the nonrepresentational features of angularity and diagonality in the visual stimulus appeared to have the ability to evoke the subjective responses that convey the meaning of threat.     

Personality in adulthood: a six-year longitudinal study of self-reports and spouse ratings on the NEO Personality Inventory

Previous longitudinal studies of personality in adulthood have been limited in the range of traits examined, have chiefly made use of self-reports, and have frequently included only men. In this study, self-reports (N = 983) and spouse ratings (N = 167) were gathered on the NEO Personality Inventory (Costa & McCrae, 1985b), which measures all five of the major dimensions of normal personality. Cross-sectional and longitudinal analyses on data from men and women aged 21 to 96 years showed evidence of small declines in Activity, Positive Emotions, and openness to Actions that might be attributed to maturation, but none of these effects was replicated in sequential analyses. The 20 other scales examined showed no consistent pattern of maturational effects. In contrast, retest stability was quite high for all five dimensions in self-reports and for the three dimensions measured at both times in spouse ratings. Comparable levels of stability were seen for men and women and for younger and older subjects. The data support the position that personality is stable after age 30.     

Role of visual information in ball catching

The present study is concerned with the perceptual information about the body and space underlying the act of catching a ball. In a series of four experiments, subjects were asked to catch a luminous ball under various visual conditions. In general, catching in a normally illuminated room was contrasted with catching the luminous ball in an otherwise completely dark room. In the third and fourth experiments, intermediate conditions of visual information were included. The results suggest that it is possible to catch a ball with one hand when only the ball is visible, but performance is better when the subject has the benefit of a rich visual environment and two hands. The second experiment indicated that subject performance does improve with practice in the dark, but time spent in the darkened room itself doesn't result in a significant decrement in performance. Results of the third study suggest that vision of one's hand does not aid in the performance of this task whereas the presence of a minimal visual frame appears to aid performance. The final study examined the relation between catching performance and body sway under similar visual conditions. Results of this experiment imply that persons who exhibit relatively little postural sway in full-room lighting performed better at this catching task.     

The development of locomotor coordination: longitudinal change and invariance

Developmental sequence, relative timing, center of gravity, and phase-plane analyses were used to study a minimum of 15 years of longitudinal, filmed data on the development of hopping in 7 children. The developmental sequences revealed common, qualitative changes in the movement of the children, although each child progressed through the changes at his/her own rate. The timing analyses showed that, in the advanced hop, the tightest limb relationships were found within the hopping leg, then between contralateral limbs of the same girdle, and then between legs and arms. Relative-timing calculations revealed (a) intralimb, timing invariances that were present in first attempts to perform the skill at age 3 and remained for 15 years across all developmental levels; (b) emergent, interlimb timings that gradually became invariant; and (c) intra- and interlimb timing showing gradual development over the 15 years. One invariant, the time between landing and deepest knee flexion, is also invariant in the walk and the run (Shapiro, Zernicke, Gregor, & Diestel, 1981). Phase plane analyses indicated that the timing of peak and zero velocities may be the coordinative constant accounting for a relative timing invariance between the two legs. Position of the body's center of gravity may explain the invariant relative time between landing and deepest knee flexion, or the explanation could lie in the "equation of constraint" regulating joint equilibrium points. The data suggest that modeling the developing hop as the evolving interaction of four vibratory systems would be promising.