Instructional cues modify performance on the Iowa Gambling Task

The current study investigated whether acute alcohol intoxication produces impaired decision-making on tasks assessing ventromedial prefrontal (VMF) cortex functioning and impulsive responding. Participants completed the Iowa Gambling Task (IGT), a decision-making test targeting the VMF, and the Newman Perseveration Task (NT), a measure of impulsivity. Personality measures of impulsivity were assessed using the Barratt Impulsiveness Scale (BIS). To encourage natural responding on both tasks, participants were falsely informed that the study was examining the effects of alcohol on memory; the impulsivity tasks were presented as 'distractor' tasks. Advantageous performance on the IGT was related to specific instructional cues as well as to knowledge about the experimental purpose. Performance of intoxicated and sober participants did not differ. A subsequent study in which the true purpose of the experiment was revealed confirmed that alcohol does not affect IGT performance. Most importantly, the instruction-sensitivity of the IGT emphasizes the importance of salient cues for decision-making.     

Levels of abstraction in orangutan (Pongo abelii) categorization

Levels of abstraction have rarely been manipulated in studies of natural concept formation in nonhumans. Isolated examples have indicated that animals, relative to humans, may learn concepts at varying levels of abstraction with differential ease. The ability of 6 orangutans (Pongo abelii) of various ages to make natural concept discriminations at 3 levels of abstraction was therefore investigated. The orangutans were rewarded for selecting photos of orangutans instead of humans and other primates (concrete level), primates instead of other animals (intermediate level), and animals instead of nonanimals (abstract level) in a 2-choice touch screen procedure. The results suggest that, like a gorilla (Gorilla gorilla gorilla) tested previously (Vonk & MacDonald, 2002), orangutans can learn concepts at each level of abstraction, and unlike other nonhumans, most of these subjects rapidly learned the intermediate level discrimination.     

Performance variability is related to change in cognition: evidence from the Victoria Longitudinal Study

Performance variability across repeated task administrations may be an important indicator of age-related cognitive functioning. In the present investigation, the authors examined whether age differences and change in inconsistency were related to 6-year (3 occasion) cognitive change. Inconsistency scores were computed from 4 reaction time tasks performed by 446 older adults (54-89 years). Replicating previous cross-sectional results, greater inconsistency was observed for older participants even after controlling for differences in response speed. New longitudinal results demonstrated (a) associations between inconsistency at baseline measurement and 6-year change in cognitive performance; (b) longitudinal change in inconsistency; and (c) intraindividual covariation between 6-year change in inconsistency and 6-year change in level of cognitive function. These findings support the view that performance variability serves as a marker of cognitive aging.     

Young adults' partner preferences and parents' in-law preferences across generations,genders, and nations

To examine cultural, gender, and parent–child differences in partner preferences, in eight countries undergraduates (n = 2,071) and their parents (n = 1,851) ranked the desirability of qualities in someone the student might marry. Despite sizable cultural differences—especially between Southeast Asian and Western countries—participants generally ranked kind/understanding (reflecting interpersonal communion) highest, and intelligent and healthy (reflecting mental/physical agency) among the top four. Students valued exciting, attractive partners more and healthy, religious partners less than parents did; comparisons with rankings by youth in 1984 (i.e., from the parents' generation) suggested cohort effects cannot explain most parent–child disagreements. As evolutionary psychology predicts, participants prioritized wives' attractiveness and homemaker skills and husbands' education and breadwinner skills; but as sociocultural theory predicts, variations across countries/decades in gendered spousal/in-law preferences mirrored socioeconomic gender differences. Collectively, the results suggest individuals consider their social roles/circumstances when envisioning their ideal spouse/in-law, which has implications for how humans’ partner-appraisal capabilities evolved.     

The intoxicated witness: effects of alcohol on identification accuracy from showups

The effect of alcohol on identification accuracy is potentially an important topic. This study examined the effects of alcohol consumption on identification accuracy from showups, the identification procedure most likely to be used by police with intoxicated witnesses. The blood alcohol level of people exposed to a target was measured. In the target-present showup condition, blood alcohol level was not significantly related to correct identification rate. In the target-absent showup condition, the higher the blood alcohol level, the more people were likely to make a false identification. Implications for law enforcement and future research directions are discussed.     

Sexual and aggressive play fighting of sibling Richardson’s ground squirrels

Play fighting in many species of squirrels can involve sexual play and aggressive play, both of which can lead to wrestling which appears superficially similar. Such convergence can make scoring of the relative frequencies of these two types of play difficult and can lead to the mistaken conclusion that they grade into one another. In this study, both staged laboratory encounters between sibling pairs and spontaneous encounters between siblings in free‐living litters of Richardson’s ground squirrels (Spermophilus richardsonii) were videotaped. Frame‐by‐frame analyses using the Eshkol‐Wachman Movement Notation were employed to record the correlated movements of attack and defense by the partners and to reveal the body areas targeted during each play bout. Whereas sexual play was organized around access to the rump, aggressive play was organized around the shoulders. Although in most cases the defender’s tactics blocked access to the respective target, when contact did occur, it involved mounting in sexual play and nosing or biting in aggressive play. Eighty‐six percent of play fights could be unambiguously categorized as either sexual or aggressive play. Of these, the majority (?80%) involved sexual play. The sex of the participants did not affect the frequency of aggressive play, but in sexual play, males initiated more attacks than females. Once initiated, each form of play fighting remained distinct—if a bout began as sexual play, it would end as sexual play. Furthermore, a counterattack following sexual play was significantly more likely to be sexual than aggressive, and vice versa for counterattacks following aggressive play. Therefore, all the evidence suggested that the two forms of play fighting were not intermixed in Richardson’s ground squirrels. Aggr. Behav. 27:323–337, 2001. © 2001 Wiley‐Liss, Inc.     

Undergraduate education majors' knowledge about suicide

Undergraduate education majors' knowledge about suicide was evaluated to identify what training they may need about suicide prevention and to explore the hypothesis that individuals previously exposed to suicide in their social context may hold higher suicide-related knowledge than those without. 71 college students completed the 50-item Expanded Revised Facts on Suicide Quiz to examine their knowledge about suicide. While overall knowledge was low for general information and for specific items concerning suicide among youth and elderly persons, knowledge was high on several items important for suicide prevention work. Higher suicide-related knowledge was found for knowing a suicide attempter, providing partial support for the hypothesis that personal experience with suicidal people may correspond with greater knowledge about suicide.     

Intertrial dependence in detection and recognition tasks

A Markov analysis revealed the existence of 1st order intertrial dependence in error and response sequences from both detection and recognition tasks. Both feedback and the introduction of a burst of white noise between trials reduced intertrial dependencies in the error sequences. Task difficulty and intertrial periods affected intertrial dependence in the response sequence.