Group Commitment and Resource Conservation: Two Field Experiments on Promoting Recycling1

Two experiments evaluated the effect of commitment on paper recycling. Using an ABA design, Experiment 1 asked 24 individuals in a retirement home to sign a 4-week group commitment pledge to recycle paper. During this intervention, the subjects recycled 47% more paper than they had during baseline. They continued to recycle at this level during a 4-week follow-up period, when the group commitment was removed. Experiment 2 evaluated the relative effectiveness of group commitment, individual commitment, and token reinforcers on paper recycling in a college dormitory. The students in all three experimental conditions recycled from three to five times more paper than those in the control group during the 4-week intervention. However, in the 3-week follow-up period, when the treatments were removed, only the individually committed subjects continued to recycle significantly more paper than the controls.     

Event order versus syntactic structure in recall of adverbial complex sentences

Two experiments using recall of sentences examined two contrasting principles of clause ordering in a type of complex sentences: the main-clause-first (syntactic) principle and the event-order (or temporal-causal order) prir ciple. In Experiment 1, these two principles were studied in complex sentences with a main clause and a subordinate adverbial clause-e.g., When she heard the thunder, she stopped playing Frisbee. In sentences of this type the subordinate clause typically describes a temporally or causally antecedent event, while the main clause describes a subsequent event in the temporal-causal sequence. These two principles make opposite predictions on what is the psychologically simpler or preferred order of the two clauses in this type of complex sentence. Results of Experiment 1 showed an overall preference in memory for main-clause-first order. In Experiment 2, complex sentences with a main clause and a subordinate clause not temporally or causally related were also used in a sentence recall task. Similar results were obtained. The implication of these findings for the determinants of linguistic structures was discussed.     

The moral reasoning of juvenile delinquents: A meta-analysis

To test the hypothesized immaturity of juvenile delinquents' moral reasoning, the results of 15 studies of the moral reasoning of juvenile delinquents were integrated quantitatively using meta-analysis. Hedges and Olkin (1985) methods were used to (a) compute effect sizes, (b) test the homogeneity of the obtained effect sizes, and (c) test the statistical significance of the pooled mean effect size. The results supported the hypothesis that the moral reasoning of juvenile delinquents is immature. It was concluded that several other issues are in need of investigation.     

Clinician preparation: Experiences with pseudostuttering : “It was the longest day of my life!”

The response of lay persons to pseudostuttering in approximately 200 spontaneous communication situations were reported and evaluated by 24 graduate students in an advanced class in fluency disorders. The students each spent a day as a “stutterer” in all speech contacts. They summarized their pseudostuttering efforts, the perceived auditor reactions, and their own feelings, in each situation. Results indicated that most lay reactions to any stuttering behavior were, at best, neutral or characterized by obvious changes in behavior. Many reactions were overtly and strongly negative. Student reactions were consistently ones of anxiety, fear, the desire to avoid, frustration, and irritation. Feelings of anger and humiliation were common. Discussion of results points out the value of pseudostuttering experience in clinician training, the possible importance of attitude and adjustment consideration in management of clients who stutter, and the apparent failure of (and need for) our profession to educate the lay public about communicative disorders.     

Cognition and metacognition at extreme altitudes on Mount Everest

The FACTRETRIEVAL2 test battery, which assesses both retrieval of general information from memory and metacognition about that retrieval, was administered to people before and after a recent expedition to Mount Everest and at extreme altitudes above 6,400 m (higher than any mountain in North America or Europe). The major findings were as follows: First, the same extreme altitudes already known to impair learning did not affect either accuracy or latency of retrieval, and this robustness of retrieval occurred for both recall and forced-choice recognition. Second, extreme altitude did affect metacognition: The climbers showed a decline in their feeling of knowing both while at extreme altitude and after returning to Kathmandu (i.e., both an effect and an aftereffect of extreme altitude). Third, extreme altitude had different effects than alcohol intoxication (previously assessed by Nelson. McSpadden, Fromme, & Marlatt, 1986). Alcohol intoxication affected retrieval without affecting metacognition, whereas extreme altitude affected metacognition without affecting retrieval; this different pattern for extreme altitude versus alcohol intoxication implies that (a) hypoxia does not always yield the same outcome as alcohol intoxication and (b) neither retrieval nor metacognition is strictly more sensitive than the other for detecting changes in independent variables.     

Evolutionary psychology,biology, and cultural evolution

Evolutionary approaches to behavior, so far from indicating that human behavioral patterns must be universal and wired, actually provide us with good reasons for expecting cultural diversity and good tools for showing how it might develop. Even gender-role related behavior may be very plastic. Highly macho male behavior may be an adaptation to dangerous ecological and economic constraints. Similarly, homicide rates differ massively from culture to culture and may be under the control of specificable ecological and economic constraints.Adapted from a symposium talk given at the annual meeting of the Society for Experimental Social Psychology, October 13, 1990, Buffalo, New York. David Buss, Nancy Cantor, and Claude Steele made helpful comments on earlier versions of this paper.     

The lateralization of language comprehension using event-related potentials

Event-Related Potentials were recorded over occipital and parietal scalp from left- and right-handed adults presented with a language and a non-language visual stimulus using a divided field, "oddball" paradigm. The major finding of interest was that the P300 component was larger over the left than the right hemisphere of the right-handers when the language stimulus was presented to the left hemisphere; there were no hemispheric differences for the left-handers, regardless of field of presentation. These results are discussed in the context of developing noninvasive measures to lateralize language function.     

Do different metamemory judgments tap the same underlying aspects of memory?

We compared the predictions from several kinds of metamemory judgments (on the same set of items), both in terms of their predictive accuracy and in terms of the commonality of predictions. Undergraduates made judgments about the ease with which they could learn each item in a list (ease-of-learning judgments); then they learned every item, either to a minimal criterion of learning or with overlearning, and made judgments about how well they knew each item (judgments of knowing); finally, they returned 4 weeks later for a retention session and made feeling-of-knowing judgments on every time they could not recall, after which a recognition test assessed predictive accuracy. Ease-of-learning judgments had the least predictive accuracy. Surprisingly, however, the recognition of nonrecalled items was predicted equally well by judgments of knowing (made 4 weeks earlier) as by feeling-of-knowing judgments (made immediately prior to recognition). Moreover, those two kinds of judgments were only weakly correlated with each other, which implies that they do not tap memory in the same way.