Attraction to Competent and Incompetent Members of Cooperative and Competitive Groups1

A laboratory experiment and a reanalysis of data collected in a previous field study examined the effects of cooperation and competition on liking for other group members who varied in competence. It was hypothesized that when other members of a cooperative group are relatively incompetent, they will tend to be disliked because they decrease the subject's chances of success. On the other hand, in competitive groups incompetent group members should not be disliked because they do not reduce the probability of the subject's success. Both the laboratory experiment and the field study found support for these suggestions. In addition, in the field study it was found that the race of the other group members did not affect these tendencies. Other results from the present study yielded information concerning some of the psychological processes that determine attraction in cooperative and competitive groups. These results were discussed in terms of their implications for the use of cooperative groups in desegregated schools.     

Time and Singular Causation—A Computational Model

Causal queries about singular cases, which inquire whether specific events were causally connected, are prevalent in daily life and important in professional disciplines such as the law, medicine, or engineering. Because causal links cannot be directly observed, singular causation judgments require an assessment of whether a co-occurrence of two events c and e was causal or simply coincidental. How can this decision be made? Building on previous work by Cheng and Novick (2005) and Stephan and Waldmann (2018), we propose a computational model that combines information about the causal strengths of the potential causes with information about their temporal relations to derive answers to singular causation queries. The relative causal strengths of the potential cause factors are relevant because weak causes are more likely to fail to generate effects than strong causes. But even a strong cause factor does not necessarily need to be causal in a singular case because it could have been preempted by an alternative cause. We here show how information about causal strength and about two different temporal parameters, the potential causes' onset times and their causal latencies, can be formalized and integrated into a computational account of singular causation. Four experiments are presented in which we tested the validity of the model. The results showed that people integrate the different types of information as predicted by the new model.     

Neuromuscular-skeletal origins of predominant patterns of coordination in rhythmic two-joint arm movement

The authors tested for predominant patterns of coordination in the combination of rhythmic flexion-extension (FE) and supination- (SP) at the elbow-joint complex. Participants (N=10) spontaneously established in-phase (supination synchronized with flexion) and antiphase (pronation synchronized with flexion) patterns. In addition, the authors used a motorized robot arm to generate involuntary SP movements with different phase relations with respect to voluntary FE. The involuntarily induced in-phase pattern was accentuated and was more consistent than other patterns. The result provides evidence that the predominance of the in-phase pattern originates in the influence of neuromuscular-skeletal constraints rather than in a preference dictated by perceptual-cognitive factors implicated in voluntary control. Neuromuscular-skeletal constraints involved in the predominance of the in-phase and the antiphase patterns are discussed.     

Correlations for number of sunspots, unemployment rate, and suicide mortality in Japan

We studied the correlations among sunspot numbers, business cycles, and suicide mortalitites. Based on data from Japan between 1971 and 2001, a significant negative correlation between sunspot numbers and unemployment rate was found, R= -.17. The correlation between suicide mortality and unemployment rate was positive for males (R=.46) and negative for females (R =-.69). Both are statistically significant. The hypothesis that variation of sun activity may affect the economy and the unemployment rate and hence increase the male suicide mortality is raised.     

Predictability of locomotion: Effects on updating of spatial situation models during narrative comprehension

We investigated how the updating of spatial situation models during narrative comprehension depends on the interaction of cognitive abilities and text characteristics. Participants with low verbal and visuospatial abilities and participants with high abilities read narratives in which the protagonist's motions in a fictitious building were either highly predictable or very hard to predict. In Experiment 1, high-ability readers updated spatial situation models only if the protagonist's motions were hard to predict, whereas low-ability readers did so only if the motions were highly predictable. In Experiment 2, facilitated integrative spatial processing compensated for the low-ability participants' resource limitations. As a result, both ability groups updated spatial situation models with hard-to-predict protagonist motions. These results highlight the interactions of cognitive abilities and text characteristics in spatial situation model updating.     

Is there a linear or a nonlinear relationship between rotation and configural processing of faces?

Research suggests that inverted faces are harder to recognise than upright faces because of a disruption in processing their configural properties. Reasons for this difficulty were explored by investigating people's ability to identify faces at intermediate angles of rotation. Participants were asked to discriminate blurred famous and unfamiliar faces presented at nine angles. Blurred faces were used to minimise featural processing strategies, and to assess the effects of rotation that are specific to configural processing. The results indicate a linear relationship between angle of rotation and recognition accuracy. It appears that configural processing becomes gradually more disrupted the further a face is oriented away from the upright. The implications of these findings for competing explanations of the face-inversion effect are discussed.     

Comments on the Institute of Medicine's 2002 report on the safety of anthrax vaccine

In April 2002, the prestigious Institute of Medicine of the National Academy of Sciences issued a final report on the safety and effectiveness of the anthrax vaccine currently in use by the United States military. It concluded that the present vaccine was completely safe and effective, but ignored evidence of several recent research studies from three different nations that have implicated vaccines, often including anthrax vaccine, in the epidemiology of Gulf War illnesses. Omissions and limitations of that report are discussed.     

Ecstasy and agony: activation of the human amygdala in positive and negative emotion

Considerable evidence indicates that the amygdala plays a critical role in negative, aversive human emotions. Although researchers have speculated that the amygdala plays a role in positive emotion, little relevant evidence exists. We examined the neural correlates of positive and negative emotion using positron emission tomography (PET), focusing on the amygdala. Participants viewed positive and negative photographs, as well as interesting and uninteresting neutral photographs, during PET scanning. The left amygdala and ventromedial prefrontal cortex were activated during positive emotion, and bilateral amygdala activation occurred during negative emotion. High-interest, unusual photographs also elicited left-amygdala activation, a finding consistent with suggestions that the amygdala is involved in vigilance reactions to associatively ambiguous stimuli. The current results constitute the first neuroimaging evidence for a role of the amygdala in positive emotional reactions elicited by visual stimuli. Although the amygdala appears to play a more extensive role in negative emotion, it is involved in positive emotion as well.     

An endogenous distributed model of ordering in serial recall

We introduce a distributed model of memory for serial order, called SOB, that produces ordered serial recall by relying on encoding and retrieval processes that are endogenous to the model. SOB explains the basic shape of the serial position curve, the pattern of errors during recall (including the balance between transpositions, omissions, intrusions, and erroneous repetitions), the effects of list length on the distribution of errors, the overall level of recall and response latency, and the effects of natural language frequency on recall performance. In addition, contrary to several recent suggestions, SOB demonstrates that distributed representations can support unambiguous recall, selective response suppression, and novelty-sensitive encoding.