Aggression and self-esteem: a diary study of children's reactivity to negative interpersonal events

The study employs a daily diary design to assess self-esteem reactivity and its association with children's aggressive behavior. We test the hypothesis that the self-esteem of aggressive children will be more reactive to negative interpersonal events than the self-esteem of nonaggressive children. Results provide partial support for the aggression/reactivity hypothesis. Aggressive children's self-esteem was more reactive to negative peer events but less reactive to negative adult events than the self-esteem of less aggressive children. These findings are discussed in relation to the experimental literature relating self-esteem instability and ego-threat to aggression and in relation to the extensive body of research on childhood aggression. Intervention implications are also considered.     

Human cognition and a pile of sand: a discussion on serial correlations and self-organized criticality

Recently, G. C. Van Orden, J. G. Holden, and M. T. Turvey (2003) proposed to abandon the conventional framework of cognitive psychology in favor of the framework of nonlinear dynamical systems theory. Van Orden et al. presented evidence that "purposive behavior originates in self-organized criticality" (p. 333). Here, the authors show that Van Orden et al.'s analyses do not test their hypotheses. Further, the authors argue that a confirmation of Van Orden et al.'s hypotheses would not have constituted firm evidence in support of their framework. Finally, the absence of a specific model for how self-organized criticality produces the observed behavior makes it very difficult to derive testable predictions. The authors conclude that the proposed paradigm shift is presently unwarranted.     

Evaluating the efficiency and community safety goals of the Broward County Mental Health Court

Mental health courts have developed as one response to persons with mental illness who are involved with the criminal justice system. This study investigated the efficiency and safety goals of one such court in Broward County, FL. Mental health court (MHC) clients spent significantly fewer days in jail for the index arrest associated with study enrollment than a comparison group. MHC clients had similar survival time to re-arrest up to one year after study enrollment. MHC clients did not significantly differ from the comparison group in self-reported aggressive acts over an 8 month follow-up period, while they did self-report significantly fewer acts of violence than the comparison group at the 8 month follow-up. These findings suggest that some of the benefits associated with the MHC reported in prior studies were not achieved at the expense of efficiency and safety.     

A neural network model of foraging decisions made under predation risk

This article develops the cognitive—emotional forager (CEF) model, a novel application of a neural network to dynamical processes in foraging behavior. The CEF is based on a neural network known as the gated dipole, introduced by Grossberg, which is capable of representing short-term affective reactions in a manner similar to Solomon and Corbit’s (1974) opponent process theory. The model incorporates a trade-off between approach toward food and avoidance of predation under varying levels of motivation induced by hunger. The results of simulations in a simple patch selection paradigm, using a lifetime fitness criterion for comparison, indicate that the CEF model is capable of nearly optimal foraging and outperforms a run-of-luck rule-of-thumb model. Models such as the one presented here can illuminate the underlying cognitive and motivational components of animal decision making.     

A diffusion model analysis of the effects of aging in the lexical-decision task

The effects of aging on response time (RT) are examined in 2 lexical-decision experiments with young and older subjects (age 60-75). The results show that the older subjects were slower than the young subjects, but more accurate. R. Ratcliff s (1978) diffusion model provided a good account of RTs, their distributions, and response accuracy. The fits show an 80-100-ms slowing of the nondecision components of RT for older subjects relative to young subjects and more conservative decision criterion settings for older subjects than for young subjects. The rates of accumulation of evidence were not significantly different for older compared with young subjects (less than 2% and 5% higher for older subjects relative to young subjects in the 2 experiments).     

Assessing model mimicry using the parametric bootstrap

We present a general sampling procedure to quantify model mimicry, defined as the ability of a model to account for data generated by a competing model. This sampling procedure, called the parametric bootstrap cross-fitting method (PBCM; cf. Williams (J. R. Statist. Soc. B 32 (1970) 350; Biometrics 26 (1970) 23)), generates distributions of differences in goodness-of-fit expected under each of the competing models. In the data informed version of the PBCM, the generating models have specific parameter values obtained by fitting the experimental data under consideration. The data informed difference distributions can be compared to the observed difference in goodness-of-fit to allow a quantification of model adequacy. In the data uninformed version of the PBCM, the generating models have a relatively broad range of parameter values based on prior knowledge. Application of both the data informed and the data uninformed PBCM is illustrated with several examples.     

Infants perceiving and acting on the eyes: tests of an evolutionary hypothesis

It has been hypothesized that an evolutionarily ancient mechanism underlies the ability of human infants to detect and act upon the direction of eye gaze of another human face. However, the evidence from behavioral studies with infants is also consistent with a more domain-general system responsive to the lateral motion of stimuli regardless of whether or not eyes are involved. To address this issue three experiments with 4-month-old infants are reported that utilize a standard face-cueing paradigm. In the first experiment an inverted face was used to investigate whether the motion of the pupils elicits the cueing effect regardless of the surrounding face context. In the second experiment pupil motion and eye gaze direction were opposed, allowing us to assess their relative importance. In a third experiment, a more complex gaze shift sequence allowed us to analyse the importance of beginning with a period of mutual gaze. Overall, the results were consistent with the importance of the perceived direction of motion of pupils. However, to be effective in cueing spatial locations this motion needs to be preceded by a period of direct mutual gaze (eye contact). We suggest that evolution results in information-processing biases that shape and constrain the outcome of individual development to eventually result in adult adaptive specializations.     

Gender bias in the diagnosis of personality disorders: the roles of base rates and social stereotypes

In all three studies described in this article, novices were trained to associate traits from the DSM-IV Cluster B personality disorder categories with four letters of the alphabet. Novices were also taught various gender associations (i.e., "base rate" information) with the categories (none, stereotype-consistent, or stereotype-inconsistent). Results showed that when no gender associations were taught (Study I), case gender did not affect ratings of case vignettes. When associations were consistent with social stereotypes (Study II), case gender influenced ratings in the expected direction. When associations were the opposite of social stereotypes (Study III), only the ratings for narcissistic and histrionic were affected. Across the three studies, these results suggested that subjects rated cases in accordance with known "base rates," but that the correspondence between base rates and stereotypic associations affected the consistency and magnitude of this base rate effect.