The effect of dehydroepiandrosterone (DHEA) on recognition memory decision processes and discrimination in postmenopausal women

In this article, the theoretical distinction between recognition memory decision and discrimination processes is used to explore the effect of dehydroepiandrosterone (DHEA) in postmenopausal women. DHEA is an adrenal steroid that diminishes with aging. It has enhanced memory in laboratory animals. An 8-week placebo-controlled, double-blind experiment in which 30 women (ages 39–70) received a 50-mg/day oral dose of DHEA for 4 weeks demonstrated that DHEA made subjects more conservative (i.e., less likely to call test items “old”) in their recognition memory decisions and enhanced recognition memory discrimination for items presented briefly. The former result may reflect an empirical regularity (Hirshman, 1995) in whichrecent strong memory experiences make participants more conservative. The latter result may reflect the effect of DHEA on visual perception, with consequent effects on memory. These results suggest the methodological importance of focusing on decision processes when examining the effects of hormones on memory.     

How to keep children safe in traffic: find the daredevils early

Crossing the street in front of oncoming vehicles poses serious danger to young children. But is each young pedestrian similarly at risk? The authors aimed to identify children who are particularly prone to making risky and potentially harmful crossing decisions. They used a simple game involving risk to classify 5- to 6-year-olds as risk takers or risk avoiders. Children classified as risk takers made more crossing decisions at a busy 1-way street than risk avoiders, tolerated shorter time intervals between initiation of the crossing decision and arrival of the next vehicle, and were more likely to cause a (hypothetical) accident. Finally, they made decisions more quickly than risk avoiders. The authors discuss the implication of these results for traffic safety programs.     

Kinesthetic estimation of the main orientations from the upright and supine positions

This work investigated the accuracy of the perception of the main orientations (i.e., vertical and horizontal orientations) with the kinesthetic modality--a modality not previously used in this field of research. To further dissociate the influence of the postural and physical verticals, two body positions were explored (supine and upright). Twenty-two blindfolded participants were asked to set, as accurately as possible, a rod to both physical orientations while assuming one of the two body positions. The horizontal was perceived more accurately than the vertical orientation in the upright position but not in the supine position. Essentially, there were no differences in the supine position because the adjustments to the physical vertical were much more accurate than they were in the upright position. The lower accuracy in the estimation of the vertical orientation observed in the upright position might be linked to the dynamics associated with the maintenance of posture.     

Differences in motivations of paid versus nonpaid volunteers

143 AmeriCorps volunteers (30 men; 113 women) and 127 college student volunteers (43 men; 84 women) completed the Volunteer Functions Inventory to assess whether monetary compensation was associated with choice to volunteer to provide educational services, e.g., tutoring, mentoring. Based on Snyder's 1993 theory of functionalism, motives of paid (AmeriCorps participants) and nonpaid (college students) volunteers were expected to differ. It was also predicted that the motives of female and male volunteers would differ. Multivariate analysis of variance confirmed these assumptions. In general, paid male participants reported perceiving numerous benefits associated with volunteering and reported stronger beliefs about such benefits. Female participants reported motives for volunteering, in contrast, which were not linked with monetary compensation. The women reported recognizing the benefits of volunteering and engaging in this activity for egoistic reasons. Their reported motives had little relation to compensation.     

Evaluation of an awareness enhancement device for the treatment of thumb sucking in children

An evaluation of the awareness enhancement device (AED) described by Rapp, Miltenberger, and Long (1998) was conducted with 2 children who engaged in thumb sucking past the age at which it was developmentally appropriate. The AED effectively suppressed thumb sucking for both children. Future research evaluating the AED is discussed.     

Motor learning as a function of KR schedule and characteristics of task-intrinsic feedback

Forty participants (age range = 18-35 years) practiced 1 of 2 versions of an aiming task (with or without spring resistance). Knowledge of results (KR) was provided to them either immediately or after a delay of 2 trials. Immediate KR led to significantly more accurate performance during the 80 trials in acquisition but significantly less accurate performance on a 40-trial retention test given 24 hr after practice. In addition, the spring version of the task was performed significantly less accurately than the no-spring version on the 24-hr retention test. Most important, a significant interaction on the 24-hr retention test revealed that performance of the no-spring version of the task, when KR had been given after a 2-trial delay, was significantly more accurate than performance of the other 3 combinations of task version and KR schedule. The results suggest that KR dependency in motor skill learning is related to familiarity with task-intrinsic feedback in addition to the schedule on which KR is presented.     

Effects of phonological length on the attentional blink for words

The authors tested whether the attentional blink (AB), a deficit in the ability to report a second target appearing within half a second of a first target, may reflect limitations for consolidating visual stimuli into working memory and awareness. Previous research has shown that people are severely limited in the rate that they can identify and report visual events presented in rapid succession. Word length was examined, a variable known to affect verbal working memory. Experiment 1 showed that the AB was modulated by the phonological length of the first target. Phonologically longer pseudowords triggered larger blink deficits. Experiment 2 also demonstrated the word-length effect on the AB using real-world stimuli, anagrams, that controlled for low-level visual differences between conditions. These data support proposals that the AB reflects a difficulty in consolidating information into working memory.