Age-related differences in working memory: ERPs reveal age-related delays in selection- and inhibition-related processes

Faulty inhibition is implicated in age-related working memory decline. ERP signs of selection and inhibition of items in working memory (WM) are, respectively, a cue-locked parietal positivity (～350 ms) and a probe-locked frontal negativity (～520 ms). To determine when in the older age range differences in selective and inhibitory processes might occur, ERPs were recorded in a WM task from 20 young (20–28), 20 young–old (60–70), and 20 old–old (71–82) adults. A 4-digit display was followed by a cue indicating which 2 of 4 digits were relevant. Proactive interference (PI), the reaction time difference between a matching and non-matching to-be-ignored digit was larger, relative to the young, in both older groups. Compared to the young, both the cue- and probe-locked activities were prolonged in the older groups. Although there were no topographic differences among the age groups, the prolonged PI and associated ERPs suggest a relative age-related deficit in inhibition.     

For the greater goods? Ownership rights and utilitarian moral judgment

People often judge it unacceptable to directly harm a person, even when this is necessary to produce an overall positive outcome, such as saving five other lives. We demonstrate that similar judgments arise when people consider damage to owned objects. In two experiments, participants considered dilemmas where saving five inanimate objects required destroying one. Participants judged this unacceptable when it required violating another’s ownership rights, but not otherwise. They also judged that sacrificing another’s object was less acceptable as a means than as a side-effect; judgments did not depend on whether property damage involved personal force. These findings inform theories of moral decision-making. They show that utilitarian judgment can be decreased without physical harm to persons, and without personal force. The findings also show that the distinction between means and side-effects influences the acceptability of damaging objects, and that ownership impacts utilitarian moral judgment.     

A Developmental Trajectory in Implicit Memory is Revealed by Picture Fragment Completion

Dissociations between performance on implicit and explicit tasks have often been taken as evidence that different neural structures subserve the two types of memory. One such dissociation involves developmental differences that emerge in explicit tasks, but which appear to be absent in implicit tasks. Such findings are consistent with the idea that implicit memory is subserved by a more primitive system that evolves earlier at both phylogenetic and ontogenetic levels. The present paper reviews previous studies that claimed to find evidence that implicit memory is fully developed in very young children. Issues of measurement error, ceiling effects, and insufficient power brought up questions about those studies with respect to the developmental issue. The present study compares performance on implicit (picture fragment completion) and explicit (free recall and recognition) memory tasks with groups ranging in age from 5–28 years. We find a reliable developmental trend in both implicit and explicit performance in which the former cannot be attributed to the operation ofexplicit memory processes. Thus, we conclude that implicit memory, like explicit memory, develops with age.     

Effects of exposure to alcohol‐related cues on racial discrimination

Prior research has shown that exposure to alcohol‐related images exacerbates expression of implicit racial biases, and that brief exposure to alcohol‐related words increases aggressive responses. However, the potential for alcohol cue exposure to elicit differential aggression against a Black (outgroup) relative to a White (ingroup) target—that is, racial discrimination—has never been investigated. Here, we found that White participants (N = 92) exposed to alcohol‐related words made harsher judgments of a Black experimenter who had frustrated them than participants who were exposed to nonalcohol words. These findings suggest that exposure to alcohol cues increases discriminatory behaviors toward Blacks.     

Proverb preferences across cultures: Dialecticality or poeticality?

Peng and Nisbett (1999) claimed that members of Asian cultures show a greater preference than Euro-Americans for proverbs expressing paradox (so-called dialectical proverbs; e.g.,Too humble is half proud). The present research sought to replicate this claim with the same set of stimuli used in Peng and Nisbett’s Experiment 2 and a new set of dialectical and nondialectical proverbs that were screened to be comparably pleasing in phrasing. Whereas the proverbs were rated as more familiar and (in Set 1) more poetic by Chinese than by American participants, no group differences were found in relation to proverb dialecticality. Both the Chinese and Americans in our study rated the dialectical proverbs from Peng and Nisbett’s study as more likable, higher in wisdom, and higher in poeticality than the nondialectical proverbs. For Set 2, both groups found the dialectical proverbs to be as likable, wise, and poetic as the nondialectical proverbs. When poeticality was covaried out, dialectical proverbs were liked better than nondialectical proverbs across both stimulus sets by the Chinese and the Americans alike, and when wisdom was covaried out, the effect of dialecticality was reduced in both sets and groups. Our findings indicate that caution should be taken in ascribing differences in proverb preferences solely to cultural differences in reasoning.