Risk-sensitive foraging theory and operant psychology.

Hastjarjo, Silberberg, and Hursh (1990) have presented data on the foraging behavior of rats and discussed it in terms of risk-sensitive foraging theory. Because risk-sensitive foraging theory is comprised of several different models, it does not lead to general predictions about when an organism should prefer a foraging option with high variance to a foraging option with low variance. Any comparison of data with the predictions of the theory must be based on an appropriate model. I draw attention to various experiments that are potentially relevant to the results reported by Hastjarjo et al. and show how the time period over which the organism must survive can influence a model's predictions about risk sensitivity.     

Counterfactual Production and Achievement Orientation in Competitive Athletic Settings1

Two studies examined the impact of achievement orientation on counterfactual production in competitive sporting situations. In Study 1, participants created counterfactuals after reading 4 vignettes. Results indicated that participants reading about winners created more subtractive and downward counterfactuals than did participants reading about losers, while participants reading about losers created more additive and upward counterfactuals than did participants reading about winners. In Study 2, using participants in 3-on-3 basketball games, achievement orientation interacted with game outcome to produce adaptive responses for participants who held a mastery orientation and maladaptive responses for participants who held an outcome orientation. In addition to achievement orientation, the margin of victory played an important role in determining the type of counterfactual produced. The implications of these findings are discussed.     

Positive evaluation of stressful experiences

Two studies were conducted to test the hypothesis that the more stressful an experience is, the more positively it will be evaluated. Stressfulness was manipulated in the two studies by means of threat of shock, and both self-report and physiological measures of stress indicated that these manipulations were highly successful. In both studies subjects who were exposed to the more stressful situation evaluated their experience as significantly more worthwhile and somewhat more interesting than did subjects exposed to the less stressful situation. Furthermore, as expected, subjects did not like the high stress experience more than the low stress experience. Implications and qualifications of these findings are discussed.     

全球生命伦理学:共识的瓦解(上)——对全球性道德的探求:生命伦理学,文化战争和道德多样性

探究道德差异的核心问题以及哪种道德意见被我们采纳,比如为了建立医疗保健伦理模式与决策方法比较传统与后传统、家族本位与个人本位之间的关系。考虑到以道德多元化定义当代人类处境,关于卫生保健政策和生命法则的反思是明智的。这个反思强调了俗世伦理学的道德多元化和为对自由和责任进行俗世化思考的结论之间分歧的意义。     

Predictors of Categorical At‐Risk High School Dropouts

The authors attempted to identify key contributing factors to school dropout among 3 categories of at‐risk students: those with low grade point averages, those who had been suspended, and those from low socioeconomic backgrounds. Logistic regression analysis of the data, which were derived from the National Longitudinal Survey of Youth‐1997 (U.S. Bureau of Labor Statistics, 2002) indicated that student dropout rates were affected differently by students' membership in the 3 at‐risk categories.     

The Effects of Weight Loss Attempts, Exercise Initiation, and Dietary Practices on Health Related Quality of Life

This study (N = 98) randomly placed participants in either a higher protein or American Heart Association diet group with each group initiating an aerobic exercise program. Body composition (BC) was measured using four different methodologies (DEXA, BIA, skinfold, BMI) along with height and weight, while Health-Related Quality of Life (HRQOL) changes were measured using the Medical Outcomes Short Form 36 (SF-36). There were no significant time/diet interactions in HRQOL scores, body fat measures, and weight with the exception of Role-Physical scores (p = .006) with posttest scores higher in participants in Diet 1. Role-Physical scores changed significantly in participants in Diet 1 (p = .0001) and Diet 2 (p = .026) with higher posttest scores in each group. Social functioning had a significant main effect for time in both groups with pretest scores in both diet groups lower than their respective posttest scores (p = .015). HRQOL pretest scores were not significantly different between groups at baseline (p = .56). ANOVA revealed no significant differences in average calories between groups (p = .88). Analysis revealed no differences in exercise in minutes (p = .66) nor statistically significant changes in BC or weight (p = .65). Conclusions: Improvements in HRQOL were demonstrated in two subscales related to physiological and psychological functioning. These novel findings add to literature suggesting that HRQOL, at least concerning social functioning, work and other daily activities (Role-Physical) may improve by initiating an exercise and dietary program even when weight loss or BC improvements have been unsuccessful.     

Infants' long-term memory for the sound patterns of words and voices

Infants' long-term memory for the phonological patterns of words versus the indexical properties of talkers' voices was examined in 3 experiments using the Headturn Preference Procedure (D. G. Kemler Nelson et al., 1995). Infants were familiarized with repetitions of 2 words and tested on the next day for their orientation times to 4 passages--2 of which included the familiarized words. At 7.5 months of age, infants oriented longer to passages containing familiarized words when these were produced by the original talker. At 7.5 and 10.5 months of age, infants did not recognize words in passages produced by a novel female talker. In contrast, 7.5-month-olds demonstrated word recognition in both talker conditions when presented with passages produced by both the original and the novel talker. The findings suggest that talker-specific information can prime infants' memory for words and facilitate word recognition across talkers.     

Characterizing aggressive behavior

In the research literature, aggressive behavior has traditionally been classified into two distinct subtypes, impulsive or premeditated. Impulsive aggression is defined as a hair-trigger aggressive response to provocation with loss of behavioral control. Premeditated aggression is defined as a planned or conscious aggressive act, not spontaneous or related to an agitated state. The present study outlines the development of a clinically useful self-report instrument, the Impulsive/Premeditated Aggression Scales (IPAS), designed to characterize aggressive behavior as predominately impulsive or predominately premeditated in nature. The IPAS showed strong reliability and validity. Analysis of the IPASscores demonstrated thepresence of two types of aggressive behavior, impulsive and premeditated, in men referred for anger problems. The aggression of most individuals in the present sample was characterized as predominately impulsive in nature (90%).     

Competitiveness among Japanese, Chinese, and American undergraduate students

Although research indicates that competitiveness, defined as the desire to win in interpersonal situations, is an important individual difference that influences a range of social interactions, little research has focused on competitiveness in cultures outside the United States. This study investigated competitiveness in three cultures by comparing Chinese (n=61), Japanese (n=232), and American (n=161) undergraduate college students. Nationality and sex were compared on two scales of the revised Competitiveness Index. Analysis indicated that American students scored higher on Enjoyment of Competitiveness than Chinese and Japanese students, but no difference was found on Contentiousness. Men scored higher than women on Enjoyment of Competition but not on Contentiousness. The findings indicate that sex and cultural patterns influence some but not all aspects of competitiveness.