Can training improve eyewitness identification? The effect of internal feature focus on memory for faces

Evidence suggests that individuals rely on external features such as hair and face shape when processing and recognising unfamiliar faces. This is problematic in a forensic setting because hairstyle can be changed easily. In two studies we examined whether training individuals to focus more on the stable, internal features of the face (e.g. eyes, nose and mouth) and hence less on the changeable external features would improve identification accuracy. In Study 1, participants were instructed to focus on: (1) internal features, (2) external features, or (3) both internal and external features. Participants’ eye movements were monitored while they studied target faces, which they later tried to identify from an array that included the target with a changed appearance. In Study 2, participants were instructed to focus on: (1) internal features, (2) external features, or (3) given no instructions. Participants were required to identify target faces from line-ups, where they were presented either unchanged or with an altered hairstyle. Results suggested that training individuals to attend to internal features of unfamiliar faces may improve identification accuracy in the common situation where external features have changed between presentation and identification. However, internal feature focus may decrease identification accuracy when external features are unchanged.     

Evaluating the relative impact of positive and negative encounters with police: a randomized experiment

Objectives

Examines the influence of positive, negative, and neutral police behavior during traffic stops on citizen perceptions of police.

Methods

Participants were randomly assigned to view a video clip of a simulated traffic stop in which the officer communicates with the driver in a positive (procedurally just), negative (procedurally unjust), or neutral manner. After viewing the video, participants completed a survey about their perceptions of police, including their level of trust in police, obligation to obey police orders, and willingness to cooperate with police.

Results

Observing positive interactions with police enhanced people’s self-reported willingness to cooperate with police, obligation to obey police and the law, and trust and confidence in police, whereas observing negative interactions undermined these outcomes. The effects of these interactions were much stronger for encounter-specific outcomes than for more general outcomes.

Conclusions

The results from this randomized experiment confirm that procedural justice can enhance people’s prosocial attitudes toward police, whereas procedural injustice can undermine these attitudes. While positive (procedurally just) interactions tend to have weaker effects than negative (procedurally unjust) interactions, this study finds little support for the notion that only negative experiences shape people’s views about the police.

     

Mutual Best Friendship Involvement, Best Friends�� Rejection Sensitivity, and Psychological Maladaptation

Rejection sensitivity (RS) refers to the tendency to anxiously expect, readily perceive, and overreact to experiences of possible rejection. RS is a clear risk factor for psychological maladaptation during early adolescence. However, there is growing evidence of significant heterogeneity in the psychological correlates of RS. To investigate when RS poses the greatest psychological risk during early adolescence, this study examines mutual best friendship involvement (or lack thereof) and the best friends?? RS as potential moderators of the associations between RS and psychological difficulties. Participants were 150 7th grade students (58 boys; M age = 13.05 years) who nominated their best friends, and reported on their RS, social anxiety, and self-esteem. Results from a series of hierarchical multiple regression analyses indicated that mutual best friendship involvement and best friends?? RS were both significant moderators when fear of negative evaluation (a type of social anxiety) served as the dependent variable. The association between RS and fear of negative evaluation was stronger for adolescents without mutual best friends than adolescents with mutual best friends. In addition, the association between RS and fear of negative evaluation was the strongest for adolescents whose best friends were highly rejection sensitive (relative to adolescents whose best friends were moderately or low in RS). Findings highlight the importance of considering best friendships in studies of RS and strongly suggest that, although having mutual best friendships may be protective for rejection sensitive adolescents, having a rejection sensitive best friend may exacerbate difficulties. The significance of friends in the lives of rejection sensitive adolescents is discussed as well as possible applied implications of the findings and study limitations.     

An Examination of the Reciprocal Relationships Between Adolescents’ Aggressive Behaviors and Their Perceptions of Parental Nurturance

This study examined reciprocal relationships between adolescents’ perceptions of parental nurturance and two types of adolescent aggressive behaviors (indirect and direct aggression) using a transactional model. Three waves of longitudinal data were drawn from the Canadian National Longitudinal Survey of Children and Youth. The sample included 1,416 (735 female) adolescents who were 10- and 11-year-olds at Time 1 and became 14-and 15-year-olds at Time 3. The findings failed to support reciprocal effects, but confirmed parental effects at different ages for girls and boys. For girls, perceptions of parental nurturance at age 10 were negatively associated with both indirect and direct aggression at age 12. For boys, perceptions of parental nurturance at age 12 were negatively associated with both aggressive behaviors at age 14. Future research should continue to investigate reciprocal effects in parent-adolescent relationships to identify developmental periods where the effect of adolescents’ or their parents’ behavior may be stronger.     

Sickle cell trait-associated deaths: a case series with a review of the literature

This study presents a series of 16 carriers of hemoglobin S (HbS) who died during various circumstances. Many of the cases were associated with mild to moderate exertion. The onset and/or duration of symptoms varied from a few minutes to several hours with many displaying a prolonged lucid interval with stable vital signs. Despite seeking medical treatment, sickle cell trait-related micro-occlusive crisis was never considered in the differential diagnosis. Several cases were associated with sudden death. In those deaths which were delayed, high anion gap and uncompensated metabolic acidosis were typical and were not heat related. Also characteristic were large increases in creatine kinase, alanine aminotransferase, and aspartate aminotransferase along with myoglobinemia. Although the antemortem diagnosis of rhabdomyolysis was made, the underlying cause was never deduced by the clinicians. The sickling found at autopsy is not always a postmortem artifact, and in the right circumstances can be diagnostic.     

Discriminating Hodgdon Pyrodex® and Triple Seven® Using Gas Chromatography–Mass Spectrometry

Abstract: Pyrodex ^® and Triple Seven ^® are black powder substitutes that often find use as fillers in improvised explosive devices, such as pipe bombs. These propellants have essentially the same overall appearance and oxidizers, but different fuels. For example, Pyrodex ^® contains sulfur, sodium benzoate, and dicyandiamide (DCDA), whereas Triple Seven ^® lacks sulfur but also contains 3‐nitrobenzoic acid. In this method, intact particles and postblast solid residues were reacted with bis(trimethylsilyl)trifluoroacetamide + 1% trimethylchlorosilane in acetonitrile for 30 min at 60°C. The resultant trimethylsilyl derivatives of the organic fuels were then analyzed by gas chromatography–mass spectrometry. Each derivative was clearly resolved from other components, and high‐quality mass spectra were obtained. In addition, characteristic fragments resulting from loss of a methyl radical from the molecular ion (m/z 163 for sulfur, m/z 171 for DCDA, m/z 179 for benzoic acid, and m/z 224 for nitrobenzoic acid) were able to be monitored.     

Morphological signs of ethanol poisoning, alcohol abstinence and chronic alcoholic intoxication in the mesocorticolimbic dopaminergic system

Forensic medical diagnostics of ethanol poisoning, alcohol abstinence, and chronic alcoholic intoxication of the mesocorticolimbic dopaminergic system remains an unresolved problem and encounters difficulties. This situation is due not only to the marked vulnerability of the neurons of the dopaminergic system but also to the fact that its mechanisms are poorly understood. The objective of the present work was to substantiate and develop diagnostic criteria for ethanol poisoning, alcohol abstinence, and chronic alcoholic intoxication of the neurons both in the mesocorticolimbic dopaminergic system and in other brain regions. The object of the study was the brain of healthy adult subjects who died from alcohol intoxication (in the period of ethanol resorption) and under conditions of alcohol abstinence (completion of the abstinence course). The purpose of the study was to elucidate factors responsible for the different degree of damage to the neurons of various identification groups (intact, hypochromic, picnomorphic, shadow) and macrogliocytes. The cells of all these types were counted at an area of 0.25 sq. mm within 4 squares each having a side of 250 mcm in length. The absolute and relative number of neurons in each group as well as the number of polyneuronal satellite cells per one intact neuron was determined. It was shown that alcohol intoxication is associated with acute swelling of and severe damage to brain neurons caused by the combination of such factors as toxic effect of ethanol, excessive production of catecholamines, and functional overstrain of dopaminergic neurons. The severity of acute alcohol damage to the neurons decreased with the distance from the mid-brain dopaminergic nuclei. Restoration of neurons during alcohol abstinence was due to compensatory activation of interactions between neurons and glial cells. It decreased in the sequence from the paranigral nucleus of the ventral portion of mesencephalic tegumentum to the medial portion of the accumbence nucleus (field 24b, layer III of field la, layer V of field 1) depending on the initial severity of acute damage in the brain region being examined. The severity of damage to the neurons of the mesocorticolimbic dopaminergic system under conditions of chronic alcohol intoxication estimated from the number of shadow neurons was similar to the degree of acute swelling associated with ethanol poisoning and decreases from a maximum in the nuclei of the mesocorticolimbic dopaminergic system to a minimum in layer III of field 1.