The importance of narcissism in predicting proactive and reactive aggression in moderately to highly aggressive children

The present study examined the importance of psychopathy-linked narcissism in predicting proactive and reactive aggression and conduct problems in a group of 160 moderately to highly aggressive children (mean age of 10 years, 9 months). Children's self-report of self-esteem and parent and teacher report of dimensions of psychopathy [narcissism, callous-unemotional (CU) traits, and impulsivity], proactive and reactive aggression, and conduct problems were collected. Composites of parent and teacher ratings of children's behavior were used. Consistent with the study's hypotheses, narcissism predicted unique variance in both proactive and reactive aggression, even when controlling for other dimensions of psychopathy, demographic variables associated with narcissism, and the alternative subtype of aggression. As hypothesized, impulsivity was significantly associated with only reactive aggression. CU traits were not related to proactive or reactive aggression once the control variables were entered. All dimensions of psychopathy predicted unique variance in conduct problems. Consistent with prediction, narcissism was not significantly related to general self-esteem, providing support that narcissism and self-esteem are different constructs. Furthermore, narcissism and self-esteem related differentially to proactive aggression, reactive aggression, and conduct problems. Furthermore, narcissism but not self-esteem accounted for unique variance in aggression and conduct problems. The importance of narcissism in the prediction of aggressive behaviors and clinical implications are discussed.     

Sustained effects of high participation in an early intervention for low-birth-weight premature infants

Effects of high participation in the Infant Health and Development Program (IHDP), an 8-site randomized trial that targeted low-birth-weight (LBW) premature infants (N=1,082), were estimated. Children in the treatment group were offered high-quality center-based care in their 2nd and 3rd years of life (full-day care, 50 weeks per year). High-dosage effects were estimated with a new methodology that found a matched comparison group within the follow-up group for those with high participation rates; these estimates were compared with traditional intention-to-treat (ITT) estimates. At age 8, effects on the Wechsler Intelligence Scale for Children Full and Verbal scales for children who attended > 400 days ranged from 7 to 10 points. For the heavier LBW infants (2,001-2,500 g), the effects were about 14 points for > 400 days; for the lighter LBW infants (< or = 2,000 g), the effects were about 8 points. These effects were all substantially higher than corresponding ITT effects. Similar but smaller effects were found for children who attended > 350 days.     

Grouping with and without attention

The effects of perceptual grouping on a line discrimination task were investigated using Moore and Egeth's (1997) paradigm. Observers judged which of two lines, presented one above the other over a matrix of spots, was longer. On some trials, larger spots at both ends of the lines formed arrowheads, thereby making possible the Müller-Lyer illusion. When observers attended only to the lines, they were not aware of the arrowheads. Yet their line judgment performance showed that they had succumbed to the illusion. When the observers' attention was directed to the arrowheads but they nevertheless failed to discern the arrowheads' orientation, their line judgments were still influenced by the illusion.     

Comparison of video- and EMG-based evaluations of the magnitude of children’s emotion-modulated startle response

We investigated the reliability and validity of a video-based method of measuring the magnitude of children’s emotion-modulated startle response when electromyographic (EMG) measurement is not feasible. Thirty-one children between the ages of 4 and 7 years were videotaped while watching short video clips designed to elicit happiness or fear. Embedded in the audio track of the video clips were acoustic startle probes. A coding system was developed to quantify from the video record the strength of the eye-blink startle response to the probes. EMG measurement of the eye blink was obtained simultaneously. Intercoder reliability for the video coding was high (Cohen’sκ = .90). The average within-subjects probe-by-probe correlation between the EMG- and video-based methods was .84. Group-level correlations between the methods were also strong, and there was some evidence of emotion modulation of the startle response with both the EMG- and the video-derived data. Although the video method cannot be used to assess the latency, probability, or duration of startle blinks, the findings indicate that it can serve as a valid proxy of EMG in the assessment of the magnitude of emotion-modulated startle in studies of children conducted outside of a laboratory setting, where traditional psychophysiological methods are not feasible.     

Pre-event stereotypes and misinformation effects in young children

This study examined the effects of pre-event stereotypes on 5-year-old children's memories for the visit of an adult male to their school. Children were read three stories in which this man was described in positive, negative, or neutral terms. Following the visit, children were read post-event narratives which contained positive and negative misinformation that was consistent and inconsistent with the pre-event stereotype. Children were then given a recognition test under inclusion and exclusion instructions. Negative misinformation was correctly rejected more often than positive misinformation. Children given a positive pre-event stereotype were more likely to accept positive misinformation than those in the other stereotype conditions. Process dissociation analyses revealed that recollection for negative misinformation was larger than for positive misinformation; the opposite was the case for familiarity.     

The Collaborative Longitudinal Personality Disorders Study (CLPS): overview and implications

The Collaborative Longitudinal Personality Disorders Study (CLPS; Gunderson et al., 2000) was developed to fill gaps in our understanding of the nature, course, and impact of personality disorders (PDs). Here, we review published findings to date, discuss their implications for current conceptualizations of PDs, and raise questions that warrant future consideration. We have found that PDs are more stable than major depressive disorder, but that meaningful improvements are possible and not uncommon. We have confirmed also that PDs constitute a significant public health problem, with respect to associated functional impairment, extensive treatment utilization, negative prognostic impact on major depressive disorder, and suicide risk. At the same time, we have demonstrated that dimensional models of PDs have clinical validity that categories do not, especially greater temporal stability. Furthermore, dimensional personality traits appear to be the foundation of behaviors described by many PD criteria. Taken together, our results lead us to hypothesize that PDs may be reconceptualized as hybrids of stable personality traits and intermittently expressed symptomatic behaviors.     

Inhibition of acoustic startle using different mechanoreceptive channels

In this experiment, we investigated the impact of vibrotactile prepulse frequency and intensity on the acoustically elicited startle response in humans. Mechanoreceptive channels differing in their sensitivity to transient stimulation have been identified in the skin. The Pacinian channel is optimally sensitive to vibrations at approximately 300 Hz and is specialized for the detection of stimulus transients, whereas the non-Pacinian I and III channels are optimally sensitive to vibrations at approximately 30 Hz. Vibrotactile prepulses with frequencies of 30 and 300 Hz and intensities of 95 and 130 mV were presented for 50 msec to the dominant hand of college students (N = 31), followed on some trials by a 95-dB broadband acoustic startle stimulus. The 300-Hz prepulses resulted in significantly more pronounced inhibition of startle magnitude, amplitude, and probability, whereas only the 30-Hz prepulses significantly facilitated blink latency. These results support the idea that the inhibition of acoustic startle is determined more by transient than by sustained aspects of vibrotactile prepulse stimuli. This study also demonstrates that different aspects of the startle response differentially reflect stimulus characteristics of the prepulse.     

"Economic man" in cross-cultural perspective: behavioral experiments in 15 small-scale societies

Researchers from across the social sciences have found consistent deviations from the predictions of the canonical model of self-interest in hundreds of experiments from around the world. This research, however, cannot determine whether the uniformity results from universal patterns of human behavior or from the limited cultural variation available among the university students used in virtually all prior experimental work. To address this, we undertook a cross-cultural study of behavior in ultimatum, public goods, and dictator games in a range of small-scale societies exhibiting a wide variety of economic and cultural conditions. We found, first, that the canonical model - based on self-interest - fails in all of the societies studied. Second, our data reveal substantially more behavioral variability across social groups than has been found in previous research. Third, group-level differences in economic organization and the structure of social interactions explain a substantial portion of the behavioral variation across societies: the higher the degree of market integration and the higher the payoffs to cooperation in everyday life, the greater the level of prosociality expressed in experimental games. Fourth, the available individual-level economic and demographic variables do not consistently explain game behavior, either within or across groups. Fifth, in many cases experimental play appears to reflect the common interactional patterns of everyday life.