Cue competition effects in the planarian

The learning abilities of planarian worms (Dugesia tigrina) were assessed by using a number of Pavlovian conditioning paradigms. Experiment 1 showed that planaria were susceptible to basic conditioning in that they readily developed a conditioned response to a change in ambient luminance when it was consistently paired with an electric shock over a number of trials. In Experiment 2, the change in luminance was presented in a compound with a vibration stimulus during conditioning. Subsequent tests revealed poor conditioning of the elements compared with control groups in which the animals were conditioned in the presence of the elements alone, an instance of overshadowing. In Experiment 3, pre-training of one of the elements before compound conditioning resulted in blocking of learning about the other element. These results add to other studies that have reported cue competition effects in animal species belonging to different phyla (chordate, mollusk, arthropod), suggesting that learning in these phyla could be ruled by similar principles. The results are discussed adopting an evolutionary-comparative approach.     

Structural equation modelling of human judgement

Structural equation modelling (SEM) is outlined and compared with two non-linear alternatives, artificial neural networks and “fast and frugal” models. One particular non-linear decision-making situation is discussed, that exemplified by a lexicographic semi-order. We illustrate the use of SEM on a dataset derived from 539 volunteers' responses to questions about food-related risks. Our conclusion is that SEM is a useful member of the armoury of techniques available to the student of human judgement: it subsumes several multivariate statistical techniques and permits their flexible combination, and it provides robust goodness-of-fit statistics and is available in (generally) easy-to-use computer packages. Although the number of tasks for which SEM provides a persuasive psychological model is small, it is very useful in identifying the important variables and their inter-relations that contribute to task performance, and thus can constitute a valuable intermediate staging point between raw data and a fully fledged psychological theory.     

Teaching Exodus as “Problem Text”

This essay explores how one might use the “problem” of the hardening of Pharaoh's heart as a learning opportunity in the classroom. The author identifies two pedagogical aims: (1) cultivating more sophisticated, critical readers of the Bible; and (2) helping students reflect on the contextual nature of interpretation. The essay discusses in some detail various ways of teaching the text, including an exercise in close reading, examination of sources, and a selective study of the history of interpretation. It also explores various lessons to be learned from these exercises, and addresses applicability of the approaches to other teaching contexts. An earlier version of this paper was prepared for the “Problem Texts” group of the consultation “Teaching the Bible in the 21st Century,” held at the Wabash Center in Crawfordsville, Indiana.     

The Relation of Parental Emotionality and Related Dispositional Traits to Parental Expression of Emotion and Children's Social Functioning

The purpose of this study was to test relations between parental temperamental emotionality and regulation or related personality characteristics and parental behavior, children's regulation, and children's social functioning. Mothers and fathers reported on their own personality and/or temperament and expressivity in the family (mothers only); parents and teachers rated children (71 girls and 99 boys; M age = 73 months) on their temperamental regulation, social competence, and problem behavior. Mothers also were observed interacting with their child, and behavioral measures of children's regulation were obtained. In general, high parental regulation and low negative emotionality were associated with positive developmental outcomes in children and more positive parental behaviors, and mothers' expression of positive emotion in the family mediated some of the relations of their dispositions to children's socioemotional functioning.     

Attention to Sex in Psychological Research as Related to Journal Policy and Author Sex

From 1969 to 1974, Developmental Psychology, but not Child Development , specified that authors analyze for sex differences. The authors examined 503 studies published in Child Development and Developmental Psychology in 1971 and 1975. Sex of senior author, subjects and experimenter(s) were recorded for each study. If subjects of both sexes were used, the presence or absence of the following were noted: (a) analysis of sex differences; (b) hypotheses regarding sex differences; (c) mention of subjects' sex in the abstract. For single-sex-subject studies, mention of subjects' sex in the discussion or conclusion was noted. Using these data as dependent variables, chi-square analyses were performed comparing: (a) the two journals; (b) 1971 and 1975 authors; and (c) male and female authors. The findings were: (a) More attention was paid to sex in Developmental Psychology when the journal had a written editorial policy regarding this factor; (b) Evidence was mixed for increasing awareness of sex as a variable between 1971 and 1975; (c) Female authors were more aware of sex than were male authors in 1971 but not in 1975; (d) In both years, authors used own-sex subjects and experimenters more than those of the opposite sex; (e) Developmental psychologists, as compared to psychologists in other areas previously examined, were more sensitive to sex as a variable.     

Stimulus-response compatibility for absolute and relative spatial correspondence in reaching and in button pressing

Three experiments tested whether stimulus-response (S-R) compatibility might be a function of absolute (as opposed to relative) spatial correspondence-that is, the distance between a stimulus and the place of response. Experiment 1 studied reaching movements toward one of two targets in response to one of six visual stimuli. Stimulus-response pairs that shared relative position were faster than those that did not, and reaction time was faster when the stimulus and one of the potential targets were in close proximity. In Experiment 2 the same effects were found when the hands started from a different position, implicating stimulus target distance, rather than stimulus-hand distance as the critical variable. Experiment 3 employed keypress responses instead of reaches, and the distance effect was nearly absent. The implications of these results are discussed in terms of categorical (e.g. left-right) vs. quantitative (e.g. distance) S-R variables in spatial compatibility.     

Blood donation is an act of benevolence rather than altruism.

OBJECTIVES: Blood donation is described as an archetypal altruistic behavior, and recruitment/retention campaigns emphasize altruism. Here, a benevolence hypothesis for blood donation (both the donor and recipient benefit) rather than the altruism hypothesis (only the recipient gains) is proposed. DESIGN: Three United Kingdom-based studies contrasted benevolence and altruism: (a) a 6-month prospective study of blood donor behavior (Study 1: N = 957), (b) a cross-sectional study of blood donors' intentions (Study 2: N = 333), and (c) an experimental study examining the effect of benevolent and altruistic messages on willingness to help across high- and low-cost helping behaviors for committed and noncommitted blood donors (Study 3: N = 200). MAIN OUTCOME: Donor behavior and intentions-willingness. MEASURES: Beliefs in personal and societal benefit (Time 1) and actual donations (Time 2) were assessed in Study 1; beliefs in benevolence, altruism, hedonism, and kinship along with donation intentions were assessed in Study 2; and empathy, donor commitment, and willingness to donate blood, money, fund-raise, and staff a telephone helpline were assessed in Study 3. RESULTS: Beliefs in personal rather than societal benefit predicted actual future donation. A path model showed that only beliefs in benevolence were associated with intentions to donate. Committed blood donors were more willing to donate blood when exposed to a benevolent message rather than an altruistic one. This effect was not observed for other forms of helping. CONCLUSIONS: The benevolence hypothesis is supported, suggesting that blood donor motivation is partly selfish. Blood donation campaigns should focus on benevolent rather than purely altruistic messages.     

Sex differences in the occupational choices of second graders

A questionnaire was administered to 61 second graders. Sexual differences in occupational choices were apparent. Boys chose twice as many occupations as girls. Of 29 occupations selected as “most desirable,” only one was mentioned by both boys and girls. Of 37 occupations selected as “least desirable,” only two were mentioned by both sexes. More boys than girls knew their father's occupation. Although 76% of the girls knew their father's occupation, they did not select that occupation for themselves. A series of hypotheses based on the above data was generated.