The role of propulsive muscles of the shoulder during quadrupedalism in vervet monkeys (Cercopithecus aethiops): implications for neural control of locomotion in primates

In comparative anatomical studies of the shoulder, the humeral retractors are often grouped together as propulsive muscles, which are important in the propulsive stroke of the forelimb during quadrupedal locomotion. Electromyographic (EMG) analyses of these muscles in opossums, cats, and dogs in general have confirmed such conclusions. An EMG study of chimpanzee shoulder muscles during knuckle-walking found, however, that the humeral retractors are either inactive or perform a function unrelated to propulsion (Larson & Stern, 1987). This contrast in muscle recruitment patterns between chimpanzees and more "typical" mammalian quadrupeds was attributed to the derived morphology of the chimpanzee shoulder. The present study examines the activity patterns of the humeral retractors in the vervet monkey, a primate more closely resembling nonprimate mammals in its shoulder morphology. The results of this EMG analysis show that despite the significant differences in anatomy between chimpanzees and vervets, the two species display very similar muscle recruitment patterns during quadrupedalism, and there is evidence for this same pattern in other species of primates. These differences in muscle activity patterns between primates and nonprimate mammals may be related to changes in the neurological control of locomotion in primates due to the evolutionary development of manipulative abilities in the primate forelimb.     

Is dependence on phonological information in children's reading a product of instructional approach?

Eight-year-old British children were found to be less accurate at rejecting pseudohomophones than ordinary nonwords in a lexical decision task, but 8-year-old New Zealand children did not show this effect. A subsequent homophone decision task showed that this difference was not due to the New Zealand children being unable to distinguish pseudohomophones from other nonwords. The New Zealand children, however, were less accurate than the British children in pronouncing the pseudohomophones they had identified. It was argued that the British children tended to sound out the items before making a choice in the lexical decision task, which gave salience to phonological rather than visual information, resulting in increased errors to the pseudohomophones. It was concluded that where the British children showed this dependency on use of phonological information it was a product of the teaching approach they had experienced.     

Agreeable fancy or disagreeable truth? Reconciling self-enhancement and self-verification

Three studies asked why people sometimes seek positive feedback (self-enhance) and sometimes seek subjectively accurate feedback (self-verify). Consistent with self-enhancement theory, people with low self-esteem as well as those with high self-esteem indicated that they preferred feedback pertaining to their positive rather than negative self-views. Consistent with self-verification theory, the very people who sought favorable feedback pertaining to their positive self-conceptions sought unfavorable feedback pertaining to their negative self-views, regardless of their level of global self-esteem. Apparently, although all people prefer to seek feedback regarding their positive self-views, when they seek feedback regarding their negative self-views, they seek unfavorable feedback. Whether people self-enhance or self-verify thus seems to be determined by the positivity of the relevant self-conceptions rather than their level of self-esteem or the type of person they are.     

Evidence for terror management theory: I. The effects of mortality salience on reactions to those who violate or uphold cultural values

On the basis of terror management theory, it was hypothesized that when mortality is made salient, Ss would respond especially positively toward those who uphold cultural values and especially negatively toward those who violate cultural values. In Experiment 1, judges recommended especially harsh bonds for a prostitute when mortality was made salient. Experiment 2 replicated this finding with student Ss and demonstrated that it occurs only among Ss with relatively negative attitudes toward prostitution. Experiment 3 demonstrated that mortality salience also leads to larger reward recommendations for a hero who upheld cultural values. Experiments 4 and 5 showed that the mortality salience effect does not result from heightened self-awareness or physiological arousal. Experiment 6 replicated the punishment effect with a different mortality salience manipulation. Implications for the role of fear of death in social behavior are discussed.     

Ask and You Shall be Given: Request Size and Donations to a Good Cause1

In an attempt to replicate the findings reported in this Journal by Weyant and Smith (1987), members or recent donors to a Canadian civil liberties organization were asked to donate money under one of three conditions: (a) In the control condition, they were simply asked for a donation; (b) in the “smaller request” condition, they were asked to make a donation, but amounts of Canadian $30 to $100 were suggested; and (c) in the “larger request” condition, amounts of $50 to $250 were suggested. Unlike the Weyant and Smith studies, we found no difference in the proportion of respondents making a donation, but significant differences in the size of the donations made by those making donations. In our study, the most effective way of getting large donations was to ask for a large amount. It was suggested that the most likely explanations for the differences in the results of the two studies were the following: First, our target population were previous donors to the organization, whereas those in the Weyant and Smith studies were not likely to have been. Previous research suggests that those who had been donors previously are influenced, positively, by requests for a specific large donation, whereas those not previously approached are, if anything, negatively influenced. Second, our “larger request” appears to be within a plausible range for donations, whereas the larger request in the Weyant and Smith study may have been seen as being outside of the plausible range. In any case, however, we would recommend caution in drawing a conclusion about the most effective request size to encourage people to donate money to charity.     

Preventive group psychotherapy for at-risk infants and their mothers

There is increased evidence that infants who receive poor quality social stimulation from their primary caregiver are at risk for later developmental difficulties. This paper describes a preventive intervention for mother-infant dyads exhibiting impaired patterns of social interaction. An impaired relationship with the primary caregiver has been found to be associated with social and emotional deficits in early childhood as well as with significant psychopathology in adulthood. The intervention consisted of group treatment of mothers and their infants. Each group session has 4 subsections which, together, were directed towards improving the mothers' ability to relate in a stimulating and nurturant manner to their children. Types of intervention included didactic instruction, modeling, and interpretation of the infant's behavior. Qualitative data suggested that the group intervention has positive effects on the mother-infant dyads.     

Thinking the Unthinkable: The Effects of Anchoring on Likelihood Estimates of Nuclear War1

“Anchoring” results from insufficient adjustment up or down from an original— often arbitrary—starting value. Six sets of surveys were designed to assess the effects of anchoring on subjective likelihood estimates of a nuclear war. Based on responses from 1600 students, results indicated that: (a) likelihood estimates were strongly susceptible to anchoring; (b) neither likelihood estimates nor the effects of anchoring were significantly influenced by the ease with which respondents could imagine a nuclear war (outcome availability), by instructions to list the most likely path to nuclear war (path availability), or by casting the problem in terms of the avoidance, rather than the occurrence, of nuclear war; (c) the effects of anchoring extended to estimates concerning the efficacy of strategic defenses; and (d) likelihood estimates were affected by anchoring even after correcting for social demand biases. In estimating the likelihood of nuclear war and otherwise attempting to “think the unthinkable”, many students responded in a manner consistent with denial; the paper concludes with a discussion of these individuals.     

The wilderness therapy program: An empirical study of its effects with adolescents in an outpatient setting

The results of a study of the Wilderness Therapy Program involving 23 adolescents in outpatient counseling are presented. Data were collected before and after four trips on measures of locus of control, behavioral symptoms, self-efficacy, self-esteem, and a number of measures designed specifically for this program. Following a one and one-half to two week backpacking trip that included daily therapy, significant change was found for locus of control, self-esteem and symptom reduction. Positive changes were noted on the other measures as well. Future directions and social work implications were discussed.     

Quantum mechanics as subjectivity and projective stimulus

In this paper I attempt to show that subjectivity, as an input to the creative core of physics, is a misunderstood, but crucial factor. Utilizing Rapaport's fundamental paper, Principles Underlying Projective Techniques which identifies the determinants of the projective technique as: 1. lack of organization, 2. undifferentiation, 3. closeness to the core of the personality, and 4. the meaning of the stimulus being unknown to the subject, a link is suggested to quantum mechanics. It is further suggested the revolutionary nature of quantum mechanics satisfies the projective criterion of the material being unorganized or unfamiliar so that the function of organization can become predominant (Rapaport 1942, p. 93).     

PROMOTING SAFETY BELT USE WITH TRAFFIC SIGNS AND PROMPTERS

Two studies were conducted examining the stimulus-control effects of conventional traffic signs as prompts for motor vehicle driver safety belt use. Following pilot research which suggested that a traffic sign reading “Fasten Safety Belt” posted at a parking lot exit was effective in producing small increases in safety belt use, Study I demonstrated the superiority of having human prompters display such signs compared to simply posting the signs. Study II replicated the findings of Study I and found that posted signs became more effective in prompting safety belt use if simple posting was preceded by a period involving human prompters who displayed the signs. The results bear upon the development of more effective use of traffic signs in promoting safety belt use and in viewing such use as an instance of rule-governed behavior.