Improving Discrimination and Face Matching with Caricature

Identification of faces from photographs is a common security measure, but matching unfamiliar faces produces high rates of error. Caricatures of familiar people are highly identifiable because they exaggerate distinctive features. We investigated whether exaggerating unfamiliar faces through caricaturing could also improve face‐matching accuracy. In Experiment 1, face‐matching arrays were caricatured relative to an average by 30%, 50% and 70%. Correct rejection of the target‐absent arrays was improved at all levels. Accurate matches increased at 30%, but at 70%, the transformation was too extreme, and all of the arrays were more likely to be rejected. In Experiment 2, photographic identification (ID) images were caricatured by 30% and 50% and matched to life‐size photographs. Rejection of foils improved, but the ID of matching images was impaired. Modest levels of caricature may improve discrimination in unfamiliar face matching, but at stronger levels, a conservative response bias may inhibit accurate ID. Copyright © 2013 John Wiley & Sons, Ltd.     

Changes in Limb Stiffness Under Conditions of Mental Stress

In 2 experiments, the effects of mental stress on limb stiffness were investigated. The relative contribution to arm stiffness of individual muscle activity, co-contraction, muscle reflexes, and postural adjustments were examined. In each experiment, participants (N = 24, Experiment 1; N = 16, Experiment 2) held their supinated hand under a tray that they were required to return to horizontal after it had been suddenly released. Electromyographic activity in the biceps and triceps muscles was recorded, as were elbow and wrist angles and tray displacement. In Experiment 1, mental arithmetic stress was shown to lead to decreased tray displacement (i.e., increased resistance) compared with displacements under the control, unstressed condition, as well as to increased elbow flexion before tray release. In Experiment 2, the increased resistance to perturbation caused by mental stress was found to be independent of initial elbow angle, but to vary as a function of the amount of upward force exerted before tray release. The authors conclude that stress-induced increases in limb stiffness result from changes in the initial position of the elbow, specified by its angle, together with the initial force exerted by participants to counteract the mechanical perturbations.     

Vocal learning of a communicative signal in captive chimpanzees, Pan troglodytes

We hypothesized that chimpanzees could learn to produce attention-getting (AG) sounds via positive reinforcement. We conducted a vocal assessment in 76 captive chimpanzees for their use of AG sounds to acquire the attention of an otherwise inattentive human. Fourteen individuals that did not produce AG sounds during the vocal assessment were evaluated for their ability to acquire the use of an AG sound through operant conditioning and to employ these sounds in an attention-getting context. Nine of the 14 chimpanzees were successfully shaped using positive reinforcement to produce an AG sound. In a post-training vocal assessment, eight of the nine individuals that were successfully trained to produce AG sounds generalized the use of these newly acquired signals to communicatively relevant situations. Chimpanzees possess the ability to acquire the use of a communicative signal via operant conditioning and can generalize the use of this newly acquired signal to appropriate communicative contexts.     

Social status, masculinity, and testosterone in young men

Among other things, sexual selection theory posits that in species with limited male parental investment, males should evolve biological mechanisms to competitively dominate or otherwise compete with one another. It is unclear whether such proposed mechanisms would influence status hierarchies in small human groups. We report the results of a study investigating possible effects of prenatal (index-to-ring finger length ratio or 2D:4D) and salivary testosterone, and masculine identification, on status among 71 male college students living in nine residential groups. The results indicate no role of either prenatal or salivary testosterone in maintaining status hierarchies in these groups. A possible explanation is that peer-assessed status in these groups was arrived at cooperatively rather than through dominance contests.     

Awareness,Perceptions, and Provider Recommendation Related to Genetic Testing for Hereditary Breast Cancer Risk among At-Risk Hispanic Women: Similarities and Variations by Sub-Ethnicity

This study explored awareness of risk factors for hereditary breast and ovarian cancer (HBOC), awareness, knowledge and concerns about genetic testing, and preference for how to have genetic testing recommended by a care provider among at-risk Hispanic women. Differences in these factors among Mexican, Cuban, and Puerto Rican women were also examined. Women with a personal or family history of breast or ovarian cancer from the Tampa Bay Area participated in a qualitative interview (N = 53). Data were analyzed using a combination of open and axial coding with a grounded theory approach. Study participants in all groups reported: being aware that family history was a breast cancer risk factor, limited knowledge of genetic testing, fear of test results, concerns about children’s risks, and no physician referral for genetic testing. Noteworthy sub-ethnic differences included preferences for physician recommendation and information about genetic testing. This study provides important preliminary information about areas related to HBOC that require additional education in the Hispanic community as a whole and by sub-ethnicity.     

Effects of Salient Multiple Identities on Women's Performance Under Mathematics Stereotype Threat

Previous research on affective extremity and social identity complexity suggested that women's mathematics stereotype threat might be alleviated by reminding individual women of their multiple roles and identities, most of which would presumably be unrelated and thus impervious to negative stereotypes regarding math performance. To test this hypothesis, we primed the relevant stereotype and then asked men and women college students to draw self-concept maps with many or few nodes. When they drew no maps or maps with few nodes, highly math-identified women scored significantly worse than highly math-identified men on a subsequent Graduate Record Examination-like math test, but when they drew maps with many nodes, they scored as well as those men. Theoretical and practical implications of the results are discussed.     

Assertion training: the effectiveness of a comprehensive cognitive--behavioral treatment package with professional nurses

The purpose of the study was to evaluate the effectiveness of a comprehensive cognitive-behavioral treatment package with a professional population of registered nurses using multiple self-report and role-play measures. Twenty-six self-referred registered nurses were randomly assigned to either a Treatment or Control group. The treatment package consisted of five weekly 2-hr sessions of group assertion training using the cognitive-behavioral model of Lange and Jakubowski. The Assertiveness Self-statement Test, the Rathus Assertiveness Schedule, the Adult Self-expression Scale, two Likert scales and role-play were used to evaluate changes over time. The results indicated: (1) the nurses in both groups at Pretreatment were clearly subassertive; (2) by Posttraining the Treatment-group members increased significantly their assertiveness as indicated on the self-report tests; (3) Treatment-group members had successfully maintained their improved assertiveness by the 2-month Follow-up; (4) the role-play ratings paralleled and supported the self-report results, but not at significant levels; (5) there was strong empirical support for the social validity of the treatment package; and (6) there was a high degree of treatment credibility for the cognitive-behavioral Assertion-training group. Overall, the results indicate clear support for the effectiveness of a broad-based cognitive-behavioral treatment package for treating subassertive behavior in a professional population of registered nurses.     

Comparison of self-concepts of students identified as gifted and regular students.

The purpose of the present study was to compare the self-concepts of 40 eighth grade students identified as gifted and 40 regular eighth grade students using the Piers-Harris Children's Self-concept Scale. A t test indicated a significant group difference on the behavior component only and no significant differences by gender. More similarities than differences were noted in self-concepts of these students identified as gifted and regular students.     

Developmental changes in apportionment of study time among items in a multitrial free recall task

First grade, third grade, and college Ss attempted to memorize a single set of items over the course of 5 trials, each trial consisting of a 45-sec study period followed by a free recall test. On all trials but the first, S was allowed to have available during his study period only half of the total set of items, but was free to select whichever items he wished to include in this half. Third grade and college Ss were significantly more prone than first grade Ss to select for study items not recalled in the immediately preceding recall test. The results suggest that the strategy of deliberately concentrating one's study activities on the less well mastered segments of materials to be learned, like other elementary memory strategies (e.g., rote rehearsal), cannot automatically be assumed to be part of a young child's repertoire of learning techniques.     

Transfer and the organization of Perceptual-Motor space

Summary Three experiments are reported involving transfer of effects of different types of visual distortion: lateral displacement, linear extent, and visual rotation. Transfer between different body parts and between different dimensions of space occur but to varying degrees. These are interpreted in terms of their implications for understanding the organization of perceptual and perceptual-motor space.This research was supported by the Center for Research in Human Learning of the University of Minnesota, and by grants 1-K3-HD 12,396, HD 03082 to the University of Minnesota. The authors are indebted to Dr. Albert Yonas for helpful discussions of the results.