Dominance,physiology, and self-aggression in monkeys

Several tests failed to detect any relationship between the amount of self-aggression (SA) and either spontaneous or contrived dominance rank of self-aggressive stumptailed macaques living in groups. SA and stereotyped movements were affected differently when the subjects were given drugs, suggesting a dissociation between these two behaviors. SA did not correlate with measured adrenocortical arousal, indicating that self-aggressive monkeys are not stressed as they are when receiving social aggression. Theories of social aggression, such as social learning theory, deal poorly with self-directed aggression.     

Can fabricated evidence induce false eyewitness testimony?

False information can influence people's beliefs and memories. But can fabricated evidence induce individuals to accuse another person of doing something they never did? We examined whether exposure to a fabricated video could produce false eyewitness testimony. Subjects completed a gambling task alongside a confederate subject, and later we falsely told subjects that their partner had cheated on the task. Some subjects viewed a digitally manipulated video of their partner cheating; some were told that video evidence of the cheating exists; and others were not told anything about video evidence. Subjects were asked to sign a statement confirming that they witnessed the incident and that their corroboration could be used in disciplinary action against the accused. See‐video subjects were three times more likely to sign the statement than Told‐video and Control subjects. Fabricated evidence may, indeed, produce false eyewitness testimony; we discuss probable cognitive mechanisms. Copyright © 2009 John Wiley & Sons, Ltd.     

Supporting child witnesses during identification lineups: Exploring the effectiveness of registered intermediaries

Performance at identification lineup was assessed in eighty‐five 6‐ to 11‐year‐old typically developing children. Children viewed a live staged event involving 2 male actors, and were asked to identify the perpetrators from 2 separate lineups (one perpetrator‐present lineup and one perpetrator‐absent lineup). Half the children took part in lineups adapted by a registered intermediary (an impartial, trained professional who facilitates understanding and communication between vulnerable witnesses and members of the justice system), and half took part in “best‐practice” lineups, according to the current guidance for eyewitness identification in England and Wales. Children receiving assistance from a registered intermediary (relative to children who received best‐practice lineups) were more accurate in their identifications for perpetrator‐present lineups, and there was some evidence that they were also more accurate for perpetrator‐absent lineups. This provides the first empirical evidence for the effectiveness of registered intermediary support during identification lineups.     

Tracking arousal state and mind wandering with pupillometry

In four experiments, the association between arousal state and different mind-wandering states was examined. Participants performed a sustained attention task while pupil responses were continuously recorded. Periodically during the task, participants were presented with thought probes to determine if they were on task or mind wandering. Across the four experiments, the results suggested that in situations that promoted on-task behaviors and focused external attention, mind wandering was associated with lowered arousal, as seen by smaller tonic pupil diameters and smaller phasic pupillary responses. However, in situations that promoted a more internal focus of attention, there were no differences between on-task states and mind wandering in tonic pupil diameter (although differences emerged for phasic pupillary responses), suggesting similar arousal levels. Furthermore, across the four experiments, mind blanking and mind wandering dissociated in terms of whether the situation promoted focused external attention or focused internal attention. These results are broadly consistent with the notion that mind wandering is a heterogeneous construct, with different forms of mind wandering being associated with different arousal states, and suggest that a combination of behavioral and pupillary measures can be used to track these various states.     

Pupillary correlates of lapses of sustained attention

The current study examined the extent to which pupillary responses (both pretrial baseline and phasic responses) would accurately track lapses of attention as predicted by theories of locus coeruleus norepinephrine (LC-NE) functioning. Participants performed a sustained attention task while pupil responses were continuously recorded. Periodically during the task, participants were presented with thought probes to determine if they were on or off task. The results suggested the pupillary responses accurately distinguished on from off-task states. Importantly, pretrial baseline pupil responses distinguished different types of lapses of attention, with inattentive and mind-wandering states being associated with small pretrial baseline pupil diameters on average and distracted states being associated with larger pretrial baseline pupil diameters on average compared to focused states. These results support the notion that pupil diameter is sensitive to different types of lapses of attention which may be associated with different LC-NE modes.     

Relating a Social Influence Model to the Role of Acculturation in Substance Use Among Latino Adolescents1

This study examined determinants of substance use derived from the theory of planned behavior as influenced by acculturation. Latino adolescents (n= 448) completed measures of attitudes, subjective norms, perceived behavioral control, intentions toward substance use, and 2 acculturation components. The degree to which Latino adolescents were exposed to as well as use Spanish was unrelated to determinants of future substance use, whereas the degree to which they interact with non-Latino peers exerted a protective effect regarding future substance use. However, both acculturation components influenced the extent social influence determinants predicted future substance use. Intervention strategies may need to consider acculturation in order to effectively direct resources toward those psychosocial determinants of substance use of greatest relevance to Latino populations.     

The relationship among sex-role stereotyping,sex-role preference,and the sex difference in spatial visualization

At an early age, children attain concepts of sex-appropriate activities, behaviors, attitudes, and goals, i.e., sex-role stereotypes. These conceptual stereotypes seem to assign a less favorable role to females. Thus it seems plausible that their acceptance (by both sexes) might be at least partly responsible for the performance differences that begin to arise in adolescence and adulthood. In view of the importance of early adolescence as a transitional period during which sex-role requirements are augmented and intellectual sex differences emerge, 105 11-year-olds and 102 14-year-olds were selected as subjects. Their spatial abilities, sex-role concepts, and sex-role preferences were assessed. Stereotyping sex roles (in general) was not associated with spatial performance; stereotyping sex roles that included information regarding subjects' views about intellectual competence was related to performance. The sex difference in spatial ability that emerged at age 14 was among subjects with own-sex preferences only; there were no sex differences among subjects who preferred to be boys.This article is based upon a doctoral dissertation presented to the Department of Psychology of Columbia University. The author would like to express her thanks to her advisers, Phillip Shaver and Deanna Kuhn; to her committee members, Robert Krauss, Norma Graham, Patrick Lee, and Wayne Proudfoot; to Carol Jacklin and Ruth Wylie for their advice and support; and to Flora Churnin, Douglas Churnin, and Carl Nash for their invaluable assistance during all phases of this study.