Inspecting the emperor's clothes: Evidence that random selection of leaders can enhance group performance.

This article tests the hypothesis that group performance might be superior when leaders are randomly rather than systematically selected. In Experiment 1 groups with randomly selected leaders performed a survival task better than groups whose leaders were systematically selected. This effect was replicated in Experiment 2: Groups with a random leader also performed better than groups with no appointed leader and followers adhered more strongly to the group decision. In Experiment 3, naive participants' experimental expectations confirmed the counterintuitive nature of these findings. Results suggest that systematically selected leaders can undermine group goals and group maintenance. The possibility that this occurs because leaders assert their personal superiority at the expense of shared social identity is discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

A comparison of normal forgetting, psychopathology, and information-processing models of reported amnesia for recent sexual trauma.

This study assessed memories for sexual trauma in a nontreatment-seeking sample of recent rape victims and considered competing explanations for failed recall. Participants were 92 female rape victims assessed within 2 weeks of the rape; 62 were also assessed 3 months postassault. Memory deficits for parts of the rape were common 2 weeks postassault (37%) but improved over the 3 month window studied (16% still partially amnesic). Hypotheses evaluated competing models of explanation that may account for reported recall deficits. Results are most consistent with information processing models of traumatic memory. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Comparing borderline definitions: DSM-III borderline and schizotypal personality disorders.

Compared the two types of borderline disorder formally defined by Diagnostic and Statistical Manual of Mental Disorders (DSM-III), borderline personality disorder and schizotypal personality disorder (SPD), at the diagnostic category and individual criterion level. Unlike previous research in this area, which had focused on inpatient and outpatient populations, the sample was a psychometrically defined, nonpatient sample including Ss meeting DSM-III criteria for each disorder. The results indicated that the two diagnostic categories each define a type of borderline with distinctive combinations of features. Perceptual and cognitive distortion, however, seem to be present in both and define an area of overlap between the two disorders. The implications of these findings for the revision of the SPD diagnostic criteria in DSM-III are discussed, and the theoretical separation of two subtypes of borderline personality is affirmed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Effects of chronic haloperidol and intermittent cocaine administration on behavior elicited by apomorphine.

Relatively little is known about the behavioral or neurophysiological effects resulting from the concurrent administration of haloperidol and cocaine. To investigate this drug interaction the effects of chronic, daily administration of haloperidol, intermittent cocaine injections, or the combination of both drug treatments on locomotion and stereotypy elicited by apomorphine in rats (Rattus norvegicus) were compared. The results indicated that, in comparison to treatment with either drug alone, the combination of daily haloperidol and intermittent injections of cocaine produced unique behavioral effects. Rats coadministered both drugs exhibited significant increases in apomorphine-induced locomotion that were maintained throughout the 64 days following suspension of drug treatment. These results are discussed in terms of the possible neurophysiological mechanisms underlying the observed behavioral changes and are related to the consequences of psychostimulant abuse in human neuroleptic treated populations. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Acoustic analysis of lexical tone in Mandarin infant-directed speech.

Using Mandarin Chinese, a "tone language" in which the pitch contours of syllables differentiate words, the authors examined the acoustic modifications of infant-directed speech (IDS) at the syllable level to test 2 hypotheses: (a) the overall increase in pitch and intonation contour that occurs in IDS at the phrase level would not distort lexical pitch at the syllable level and (b) IDS provides exaggerates cues to lexical tones. Sixteen Mandarin-speaking mothers were recorded while addressing their infants and addressing an adult. The results indicate that IDS does not distort the acoustic cues that are essential to word meaning at the syllable level; evidence of exaggeration of the acoustic differences in IDS was observed, extending previous findings of phonetic exaggeration to the lexical level. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

The Landsat Image Mosaic of Antarctica

The Landsat Image Mosaic of Antarctica (LIMA) is the first true-color, high-spatial-resolution image of the seventh continent. It is constructed from nearly 1100 individually selected Landsat-7 ETM⁺ scenes. Each image was orthorectified and adjusted for geometric, sensor and illumination variations to a standardized, almost seamless surface reflectance product. Mosaicing to avoid clouds produced a high quality, nearly cloud-free benchmark data set of Antarctica for the International Polar Year from images collected primarily during 1999–2003. Multiple color composites and enhancements were generated to illustrate additional characteristics of the multispectral data including: the true appearance of the surface; discrimination between snow and bare ice; reflectance variations within bright snow; recovered reflectance values in regions of sensor saturation; and subtle topographic variations associated with ice flow. LIMA is viewable and individual scenes or user defined portions of the mosaic are downloadable at http://lima.usgs.gov. Educational materials associated with LIMA are available at http://lima.nasa.gov.     

Differences between more and less effective psychotherapists: A study of select therapist variables.

Examined differences between more and less effective trainee psychotherapists. Therapists were assigned to one of two groups depending on whether the preponderance of their patients' changes in symptomatology indicated more or less improvement over the course of therapy. Therapist variables included emotional adjustment, relationship skills, eliciting patient involvement, credibility, directiveness, and theoretical orientation. Less effective therapists were revealed to have lower levels of empathic understanding, to rate their patients as more involved in treatment, and to rate themselves as more supportive than the more effective therapists. Less effective therapists also valued comfort and stimulation significantly more and valued intellectual goals significantly less than did more effective therapists. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Internal and external moderators of the effect of variety on food intake.

Many factors contribute to how much we eat. One such factor is the variety of different foods available. The current article reviews the variety literature with a specific focus on the factors that moderate the effects of variety on food intake and that moderate the processes that may underlie the variety effect (i.e., sensory-specific satiety and monotony). The moderators have been categorized as being of either an internal nature or an external nature. The literature suggests that internal moderators, including characteristics such as gender, weight, and dietary restraint, do not act as moderators of the variety effect. One possible exception to the absence of internal moderators is old age. Alternatively, external moderators, such as particular properties of food and the eater’s perception of the situation, appear to affect the strength of the variety effect on intake to some degree. An evolutionary hypothesis may account for the distinct roles that internal and external variables play in moderating the variety effect. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Using constraints to create novelty: A case study.

The development of Richard Serra’s sculpture is presented as a case study using a constraint-based model of novelty (Stokes, 2005, 2007). The model was developed from two problem-solving precedents: Reitman’s (1965) idea that paired constraints direct and limit search in a problem space; and Simon’s (1973), that search can only lead to novel solutions if the problem space is ill-structured. Ill-structured means that a problem space is incompletely specified or defined. The study shows how paired constraints restructure problem spaces in ways that make novelty possible and probable (Stokes, 2007). Possible means that novelty may or may not happen; probable, that paired constraints facilitate the happening. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Correction to Amodio et al. (2008).

Reports an error in "Individual differences in the regulation of intergroup bias: The role of conflict monitoring and neural signals for control" by David M. Amodio, Patricia G. Devine and Eddie Harmon-Jones (Journal of Personality and Social Psychology, 2008[Jan], Vol 94[1], 60-74). In this article, there was an error in Figure 4. The corrected figure is provided in this erratum. (The following abstract of the original article appeared in record 2007-19165-005.) Low-prejudice people vary considerably in their ability to regulate intergroup responses. The authors hypothesized that this variability arises from a neural mechanism for monitoring conflict between automatic race-biased tendencies and egalitarian intentions. In Study 1, they found that low-prejudice participants whose nonprejudiced responses are motivated by internal (but not external) factors exhibited better control on a stereotype-inhibition task than did participants motivated by a combination of internal and external factors. This difference was associated with greater conflict-monitoring activity, measured by event-related potentials, when responses required stereotype inhibition. Study 2 demonstrated that group differences were specific to response control in the domain of prejudice. Results indicate that conflict monitoring, a preconscious component of response control, accounts for variability in intergroup bias among low-prejudice participants. (PsycINFO Database Record (c) 2010 APA, all rights reserved)