Likable co-witnesses increase eyewitness accuracy and decrease suggestibility

This study examines the impact of likability on memory accuracy and memory conformity between two previously unacquainted individuals. After viewing a crime, eyewitnesses often talk to one another and may find each other likable or dislikable. One hundred twenty-seven undergraduate students arrived at the laboratory with an unknown confederate and were assigned to a likability condition (i.e., control, likable or dislikable). Together, the pair viewed pictures and was then tested on their memory for those pictures in such a way that the participant knew the confederate's response. Thus, the participant's response could be influenced both by his or her own memory and by the answers of the confederate. Participants in the likable condition were more accurate and less influenced by the confederate, compared with the other conditions. Results are discussed in relation to research that shows people are more influenced by friends than strangers and in relation to establishing positive rapport in forensic interviewing.     

In Defence of Kripkenstein: On Lewis’ Proposed Solution to the Sceptical Argument

Abstract

In Wittgenstein: On Rules and Private Language, Saul Kripke argues for an extreme form of meaning scepticism. One influential reply to Kripke’s arguments was developed by David Lewis. The reply developed by Lewis makes use of the notion of mind-independent relations of similarity and difference. The aim of the paper is to argue that Lewis’ reply is not satisfactory: the challenge to find a refutation of Kripke’s sceptical arguments remains unmet.     

How job characteristics relate to need satisfaction and autonomous motivation: implications for work effort

To explore the motivational potential of job design, we linked job demands and job resources, as defined in the job demands–resources model, to the motivational process defined in self‐determination theory. Specifically, we introduced basic need satisfaction and autonomous motivation as consecutive process variables mediating the relationship between job design and work effort. We tested this model by means of structural equation modeling in a sample of 689 employees. The comparison of several competing models provided support for the hypothesized model. We conclude that job demands thwart and job resources promote the fulfillment of 3 psychological needs. High levels of need satisfaction, in turn, are associated with autonomous motivation and, therefore, with high levels of effort.     

Interplay of Biomechanical Constraints and Kinematic Strategies in Selecting Arm Postures

In this study, the authors examined the interplay between biomechanics and control strategies in the resolution of excess degrees of freedom at the joint level. Seven participants made aimed arm movements from 30 starting points and several starting postures to targets. Final arm postures for movements to a target exhibited substantial joint angle variation. Through regression modeling and by comparing observed final arm postures with biomechanically plausible postures, the authors identified 3 kinematic strategies: (a) Maintain deviations from the average angle at the starting point to the joint's final posture; (b) make torso rotations that are a fixed proportion of shoulder rotations; and (c) adopt a characteristic combination of 4 wrist-positioning approaches. The results demonstrated that kinematic strategies can account for substantial variance in final arm postures, if one takes into account 2 types of individual differences—those that arise inevitably from biomechanical constraints and those that reflect choices in movement strategy.     

The Semantics of Secrecy: Young Children's Classification of Secret Content

The authors explored whether young children can distinguish potential secrets from nonsecrets by their content, as can older children, adolescents, and adults. Ninety children, 4, 5, and 6 years old, rated the secrecy of items from an adult-validated list of personal information about an age- and gender-appropriate puppet. Two factors of the children's data corresponded to the adult categories of nonsecrets and secrets, and a third factor corresponded to surprises. All ages rated surprises as significantly more secret than nonsecret items; however, the surprise items contained linguistic cues to secrecy. A tendency to rate nonsecrets as secret decreased with age, but only the 6-year-olds rated secrets other than surprises as significantly more secret than nonsecrets. Thus, children acquire the implicit rules defining secret content from a somewhat later age than that reported for the cognitive or behavioral capacities for secrecy.     

Physical and Observational Practice Afford Unique Learning Opportunities

In 2 experiments, the authors studied the effectiveness of physical and observational practice on learning and the effect on learning of combining physical practice and observation, as compared with providing physical practice alone. In Experiment 1, retention and transfer performance of 30 university students after physical, observational, or no practice were contrasted. Consistent with findings from other studies, the retention results indicated that observational practice is inferior to physical practice. The transfer data indicated no differences between observation and physical practice groups. In Experiment 2, retention and transfer performance of 30 participants in physical and combined (alternating physical and observational) practice groups were contrasted. The retention results showed no differences between the combined and physical practice groups, but the combined group performed significantly better than the physical practice group on the transfer test. Those findings suggest that a combination of observation and physical practice permits unique opportunities for learning beyond those available via either practice regimen alone.     

Offline Improvement during Motor Sequence Learning Is Not Restricted to Developing Motor Chunks

Robust offline performance gains, beyond those that would be anticipated by being exposed to additional physical practice, have been reported during procedural learning and have been attributed to enhancement consolidation, a process by which memory is transformed in such a way that it is not only more resistant to forgetting but may also involve a reorganization of information that supports superior task execution. The authors assessed the impact of increasing within-session practice extent on the emergence of offline performance gains. Practice-dependent improvements occurred across 12 and 24 30-s practice trials of a 5-element motor sequencing task. Offline improvements were observed following both 12 and 24 trials. The improvement following 12 trials was associated with the formation of motor chunks important for establishing movement sequence structure. In contrast, the offline improvement after 24 trials was not related to further changes in movement structure beyond those that had emerged during practice. These data suggest that additional memory operations, beyond those needed to amalgamate subsequences of the SRT task, are susceptible to enhancement consolidation.     

No evidence of racial discrimination in criminal justice processing: Results from the National Longitudinal Study of Adolescent Health

One of the most consistent findings in the criminological literature is that African American males are arrested, convicted, and incarcerated at rates that far exceed those of any other racial or ethnic group. This racial disparity is frequently interpreted as evidence that the criminal justice system is racist and biased against African American males. Much of the existing literature purportedly supporting this interpretation, however, fails to estimate properly specified statistical models that control for a range of individual-level factors. The current study was designed to address this shortcoming by analyzing a sample of African American and White males drawn from the National Longitudinal Study of Adolescent Health (Add Health). Analysis of these data revealed that African American males are significantly more likely to be arrested and incarcerated when compared to White males. This racial disparity, however, was completely accounted for after including covariates for self-reported lifetime violence and IQ. Implications of this study are discussed and avenues for future research are offered.