Different levels of complexity in the play-fighting by muroid rodents appear to result from different levels of intensity of attack and defense

Play-fighting in deer mice, Peromyscus maniculatus bairdii, prairie voles, Microtus ochrogaster, and montane voles, M. Montanus, was compared to that of laboratory rats, Rattus norvegicus. Play in rats appears more complex for two reasons: 1) more of the playful contacts elicit defensive behaviors, and 2) more of these defenses lead to counterattacks, and hence, role reversals between attackers and defenders. Neither high levels of defense, as shown by montane voles, nor high levels of counterattack, as shown by prairie voles, produce rat-like play-fighting. This only occurs when high rates of defense involving turning to face the attacker and counterattack are combined, as in rats. These two components are rarely combined together by deer mice, and so this species rarely exhibits rat-like play-fighting. Furthermore, playful counterattack appears to arise from playful attack, and not from an escalation of defense. These data suggest that the more complex forms of social play, such as play-fighting, have evolved, in part, via the escalation of defense in response to playful attack.     

Problem solving and the search for crucial evidence

Summary Four experiments are reported that examine performance on a complex reasoning task. Subjects have to determine which factory has polluted a river by ordering a series of tests for the presence or absence of various pollutants. Previous research has shown that people typically employ a non-optimal exhaustive search stragegy on this task. Experiments 1 and 2 attempt to identify some of the boundary conditions of this strategy. It is found that the order in which pollutants appear on the matrix list does not seem to be a critical factor, whereas the overall size of the factory-pollutant matrix is. Experiments 3 and 4 attempt to deter people directly from adopting the exhaustive strategy. The results show that even when people are deterred from using the exhaustive method, this will not necessarily result in their adopting a more efficient strategy.     

Cross-sex comparisons: A word of caution

A cross-sex difference on one variable is often hypothesized to be related to a gender difference on a second variable. However, caution should be exercised in making such comparative hypotheses. We gathered the expected and actual examination grades for 168 female and 163 male college students. As in prior research, males had higher expectancies than females (p<.05). But analysis of the intrasex regression equations indicated that the relationship of expectancies to performance was different for women than it was for men. Thus, a cross-sex difference in expectancies did not correspond to a parallel difference in grades. This finding highlights the potential hazards of making certain cross-sex comparisons, and we argue for more caution in their application.     

Nonlinear and Nonmonotonic Effects of Outcome on Procedural and Distributive Fairness Judgments1

It has generally been assumed that increases in the concrete outcomes of a procedure will result in judgments of greater procedural and distributive fairness, but research on this topic has been inconsistent. Using a classic procedural justice paradigm (Walker, LaTour, Lind, &. Thibaut, 1974), the experiment tested the effects of four levels of outcome. Forty-eight male and female undergraduates were led to believe that their team had been wrongfully charged with cheating in a business simulation game. An adversary adjudication was held, purportedly to resolve the charge. The outcome of the adjudication was confiscation of all, two thirds, one third, or none of the subject's monetary winnings from the game. Both procedural and distributive fairness measures showed dear nonlinear outcome effects. The relationship between outcomes and both fairness measures showed some evidence of being nonmonotonic as well: A two-thirds loss resulted in less favorable reactions than did a total loss. Ratings on other scales suggest that the nonlinear effects are due to beliefs that the judge did not fully consider the evidence in the two-thirds loss and one-third loss conditions. The discussion focuses on the theoretical implications of the findings for procedural justice and social exchange processes and the practical implications for conflict resolution procedure.     

Children's affective,behavioral, and cognitive responses to social comparison

Relative outcomes in social commerce with peers are potent determinants of cognitions and behavior in young children. Although there has been considerable attention given to the behavioral consequences of social comparisons following the receipt of rewards, there has been less concern with cognitive or affective consequences. Additionally, little is known about the accrued effects of multiple social comparison experiences that may be consistent or inconsistent with one another. In the present study, young children received a constant level of reward but the amount they saw a peer receive was varied. There were two sequences of reward distribution, and in a given sequence children received either the same number of rewards as the peer (=), more (+), or fewer (?). In a 3 × 3 factorial design all possible combinations occurred. A negative inequality in reward distribution, no matter where it fell in a sequence, made children sad and inclined children to distribute fewer rewards to peers. When a sequence contained an initial experience of positive inequality, children decreased subsequent levels of self-reward. Experiencing a comparison that revealed a negative inequality in reward distribution also disrupted children's accuracy in appraising the overall distribution of rewards: even when an initial negative inequality was completely offset by an equivalent experience of positive inequality, children inaccurately concluded that they had received fewer rewards than their peers.     

Lateral asymmetry in visual detection under hypnosis

It has been suggested that the hypnotic state results in a greater relative activation or priming of the right cerebral hemisphere than of the left hemisphere. The experiment reported here employed hypnosis to produce such a priming effect in a visual-detection task. Subjects were required to detect the presence or absence of a gap in outline squares presented either to the left visual field or right visual field, with response time as the primary dependent measure. Those subjects who were hypnotized produced a 50-msec. response time difference favoring squares presented to the left visual field whereas control subjects and simulator-control subjects showed no lateral asymmetries. The result is classified as a material-nonspecific priming effect and discussed with regard to the nature of processing resources.     

Time went by so slowly: Overestimation of event duration by males and females

In three experiments, 469 subjects watched a short videotape of a bank robbery and later estimated the duration of the tape. Subjects invariably overestimated the durations. Accuracy of time estimation was unrelated to amount of free recall (Experiment 1) or accuracy of memory (Experiment 2). Females overestimated to a greater degree than males (Experiments 2 and 3). A more stressful version of the event produced greater overestimates than a less stressful version (Experiment 3). The relationship between induced arousal and time estimation appears to be different for men and women.