Risk factors for adolescent marijuana use across cultures and across time.

An integrated analysis of the data from 3 different studies was conducted to examine the early psychosocial predictors of later marijuana use among adolescents. Longitudinal analysis of interview data was performed. The data used in the analysis were derived from (a) a sample of 739 predominantly White adolescents representative of the northeastern United States, (b) a sample of 1,190 minority adolescents from the East Harlem section of New York City, and (c) a sample of 1,374 Colombian adolescents from two cities in Colombia, South America. In 2 of the samples, participants were interviewed in their homes, and in the 3rd study, participants were assessed in school. The predictors included a number of variables from (a) the personality domain, reflecting the adolescents' conventionality and intrapsychic functioning; (b) the family domain, representing the parent-child mutual attachment relationship and parental substance use; (c) the peer domain, reflecting the peer group's delinquency and substance use; and (d) the adolescents' own use of legal drugs. The dependent variable was adolescent marijuana use. The results of the analysis demonstrated remarkable consistency in the risk and protective factors for later marijuana use across the 3 samples, attesting to the robust nature of these predictors and their generalizability across gender, time, location, and ethnic/cultural background. These findings have important implications for designing intervention programs. Programs aimed at preventing adolescent marijuana use can be designed to incorporate universal features and still incorporate specific components that address the unique needs of adolescents from different groups.     

Can false memories be corrected by feedback in the DRM paradigm?

Normal processes of comprehension frequently yield false memories as an unwanted by-product. The simple paradigm now known as the Deese/Roediger-McDermott (DRM) paradigm takes advantage of this fact and has been used to reliably produce false memory for laboratory study. Among the findings from past research is the difficulty of preventing false memories in this paradigm. The purpose of the present experiments was to examine the effectiveness of feedback in correcting false memories. Two experiments were conducted, in which participants recalled DRM lists and either received feedback on their performance or did not. A subsequent recall test was administered to assess the effect of feedback. The results showed promising effects of feedback: Feedback enhanced both error correction and the propagation of correct recall. The data replicated other data of studies that have shown substantial error perseveration following feedback. These data also provide new information on the occurrence of errors following feedback. The results are discussed in terms of the activation-monitoring theory of false memory.     

Stress modulates the use of spatial versus stimulus-response learning strategies in humans

Animal studies provided evidence that stress modulates multiple memory systems, favoring caudate nucleus-based "habit" memory over hippocampus-based "cognitive" memory. However, effects of stress on learning strategy and memory consolidation were not differentiated. We specifically address the effects of psychosocial stress on the applied learning strategy in humans. We designed a spatial learning task that allowed differentiating spatial from stimulus-response learning strategies during acquisition. In 13 subsequent trials, participants (88 male and female students) had to locate a "win" card out of four placed at a fixed location in a 3D model of a room. Relocating one cue in the last trial allowed inferring the applied learning strategy. Half of them participated first in the "Trier Social Stress Test." Salivary cortisol and heart rate measurements were taken. Stressed participants used a stimulus-response strategy significantly more often than controls. Subsequent verbal report revealed that spatial learners had a more complete awareness of response options than stimulus-response learners. Importantly, learning performance was not affected by stress. Taken together, stress prior to learning facilitated simple stimulus-response learning strategies in humans-at the expense of a more cognitive learning strategy. Depending on the context, we consider this as an adaptive response.     

Memory search following valid and invalid abrupt-onset cues

The impact of abrupt-onset cues on memory search was investigated, where the abrupt-onset cue was a valid (Experiment 1), random (Experiment 2), or irrelevant (Experiment 3) predictor of the location containing the test probe. In Experiment 4, the abrupt-onset cue either preceded or followed the test probe. Sternberg-like functions were obtained in Experiments 1 and 2, with the effects of the abrupt-onset cue localized primarily in the intercept rather than the slope. Experiment 3 demonstrated that a spatially separated and irrelevant abrupt-onset cue increased latency even when all memory probes occurred at the fixation point. In Experiment 4, the robust impact of an abrupt-onset cue vanished, regardless of stimulus onset asynchrony, when it followed the target. We concluded that abrupt-onset cues captured attention regardless of their predictability, manifested as a delaying of search. However, once attention was captured by the target, a subsequent abrupt-onset stimulus had no effect. These results were discussed in terms of diffuse attention and contingent capture models of attention.     

The development of expert face processing: are infants sensitive to normal differences in second-order relational information?

Sensitivity to second-order relational information (i.e., spatial relations among features such as the distance between eyes) is a vital part of achieving expertise with face processing. Prior research is unclear on whether infants are sensitive to second-order differences seen in typical human populations. In the current experiments, we examined whether infants are sensitive to changes in the space between the eyes and between the nose and the mouth that are within the normal range of variability in Caucasian female faces. In Experiment 1, 7-month-olds detected these changes in second-order relational information. Experiment 2 extended this finding to 5-month-olds and also found that infants detect second-order relations in upright faces but not in inverted faces, thereby exhibiting an inversion effect that has been considered to be a hallmark of second-order relational processing during adulthood. These results suggest that infants as young as 5 months are sensitive to second-order relational changes that are within the normal range of human variability. They also indicate that at least rudimentary aspects of face processing expertise are available early in life.     

A grotesque and dark beauty: How moral identity and mechanisms of moral disengagement influence cognitive and emotional reactions to war

Two studies examine the extent to which moral identity and moral disengagement jointly drive reactions to war. Study 1 finds support for a hypothesized positive relationship between moral disengagement and the perceived morality of a highly punitive response to the perpetuators of the September 11th attacks. It also finds that this effect was eliminated for participants who place high self-importance on their moral identities. Study 2 finds that moral disengagement effectively reduced the extent to which participants experienced negative emotions in reaction to abuses of Iraqi detainees by American soldiers; however, the effectiveness of moral disengagement was negated when participants’ moral identities were primed.     

The cost of event-based prospective memory: salient target events

Evidence has begun to accumulate showing that successful performance of event-based prospective memory (PM) comes at a cost to other ongoing activities. The current study builds on previous work by examining the cost associated with PM when the target event is salient. Target salience is among the criteria for automatic retrieval of intentions according to the multiprocess view of PM. An alternative theory, the preparatory attentional and memory processes theory, argues that PM performance, including retrieval of the intent, is never automatic and successful performance always will come at a cost to other ongoing activity. The 4 experiments reported here used a salient PM target event. In addition, Experiments 3 and 4 were designed to meet the stringent criteria proposed for automatic retrieval of intentions by multiprocess theory, and, yet, in all 4 experiments, delayed intentions interfered with ongoing task performance.     

Effect of a signalled delay between an action and outcome on human judgement of causality

Three experiments examined the influence of a stimulus inserted between an action (pressing the space bar of a computer) and an associated delayed outcome (a triangle lighting up on the screen) on ratings of the causal effectiveness of that action. In Experiment 1, subjects rated an action that produced an outcome immediately as more causally effective than an action that produced a delayed outcome. The rating of the causal effectiveness of an action that produced a delayed outcome in which the delay was filled by a stimulus was higher than the rating of actions that produced the outcome after an unsignalled delay. In Experiment 2, the effect of a stimulus presented uncorrelated with the action or the outcome was examined and found not to enhance the rating of causal effectiveness of an action that produced a delayed outcome. In Experiment 3, the degree of correlation between the stimulus and the consequence was examined. Ratings of the causal effectiveness of the action were greater the higher percentage of delay intervals that were signalled.