The development and flexibility of gaze alternations in bonobos and chimpanzees

Infants’ early gaze alternations are one of their first steps towards a sophisticated understanding of the social world. This ability, to gaze alternate between an object of interest and another individual also attending to that object, has been considered foundational to the development of many complex social‐cognitive abilities, such as theory of mind and language. However, to understand the evolution of these abilities, it is important to identify whether and how gaze alternations are used and develop in our closest living relatives, bonobos (Pan paniscus) and chimpanzees (Pan troglodytes). Here, we evaluated the development of gaze alternations in a large, developmental sample of bonobos (N = 17) and chimpanzees (N = 35). To assess the flexibility of ape gaze alternations, we tested whether they produced gaze alternations when requesting food from a human who was either visually attentive or visually inattentive. Similarly to human infants, both bonobos and chimpanzees produced gaze alternations, and did so more frequently when a human communicative partner was visually attentive. However, unlike humans, who gaze alternate frequently from early in development, chimpanzees did not begin to gaze alternate frequently until adulthood. Bonobos produced very few gaze alternations, regardless of age. Thus, it may be the early emergence of gaze alternations, as opposed gaze alternations themselves, that is derived in the human lineage. The distinctively early emergence of gaze alternations in humans may be a critical underpinning for the development of complex human social‐cognitive abilities.     

Is cognition the secret to working dog success?

Animal Cognition - Dogs’ special relationship with humans not only makes them ubiquitous in our lives, but working dogs specifically perform essential functions for us such as sniffing out...     

Psychopathy and the predictive validity of the PCL-R: an international perspective

Its controversial past notwithstanding, psychopathy has emerged as one of the most important clinical constructs in the criminal justice and mental health systems. One reason for the surge in theoretical and applied interest in the disorder is the development and widespread adoption of reliable and valid methods for its measurement. The Hare PCL-R provides researchers and clinicians with a common metric for the assessment of psychopathy, and has led to a surge in replicable and meaningful findings relevant to the issue of risk for recidivism and violence, among other things. Most of the research thus far has been based on North American samples of offenders and forensic psychiatric patients. We summarize this research and compare it with findings from several other countries, including England and Sweden. We conclude that the ability of the PCL-R to predict recidivism, violence, and treatment outcome has considerable cross-cultural generalizability, and that the PCL-R and its derivatives play a major role in the understanding and prediction of crime and violence.     

Affect and sensation seeking

The notion that affective responses differentiate high from low sensation-seekers was investigated. Male subjects with extremely high (N=13) or low (N=13) scores on Form V of the Sensation Seeking Scale (SSS) were presented with tones of 60, 80, and 100 dB in successive blocks of 10 tones each. Although measures of arousal (verbal self-reports and physiological measures of the orienting response) did not differentiate between high and low sensation-seekers, a self-report measure of pleasure did: Whereas reported pleasure of the low sensation-seekers began high and declined as tones became successively louder, the reported pleasure of the high sensation-seekers remained more constant across the blocks of tones.The research on which this paper was based was supported by Grant MT-4511 from the Medical Research Council of Canada to Robert Hare.     

A research scale for the assessment of psychopathy in criminal populations

This paper describes an early phase in the development of new research scale for the assessment of psychopathy in criminal populations. The scale is meant to be a sort of operational definition of the procedures that go into making global ratings of psychopathy. While the interrater reliability of these ratings is very high ( > 0.85) they are difficult to make, require a considerable amount of experience, and the procedures involved are not easily communicated to other investigators. Following a series of analyses, 22 items were chosen as representative of the type of information used in making global ratings. Two investigators then used interview and case-history data to complete the 22-item checklist for 143 male prison inmates. The correlation between the two sets of total checklist scores was 0.93 and coefficient alpha was 0.88, indicating a very high degree of scale reliability. The correlation between the total checklist scores and global ratings of psychopathy was 0.83. A series of multivariate analyses explored the factorial structure of the scale and demonstrated its ability to discriminate very accurately between inmates with high and low ratings of psychopathy. Preliminary indications are that the checklist will hold up well to crossvalidation.     

The relationship of maternal mentalization and executive functioning to maternal recognition of infant cues and bonding

The study examined associations between maternal mentalization ability, executive functioning, recognition of infant cues, and bonding in a non‐clinical sample of mothers. It employed a correlational design. Sixty‐four mothers of young infants completed assessments of mentalization ability, executive functioning, and bonding. Photographs of infant facial expressions were utilized to assess ability to recognize infant cues of emotion, but this was not found to correlate with either maternal mentalization or executive functioning ability. Whilst a trend towards a significant positive relationship between mothers' cued ability to attribute mental states and their ability to recognize infant facial expressions was observed, no significant relationships were found between bonding scores and performance on the executive functioning and mentalization measures. The present study contributes to our current understanding of the influence of maternal cognitive factors, specifically mentalization and executive functioning, on the development of the mother–infant relationship. Future research, methodological issues, and clinical and theoretical implications are discussed.     

Brain potentials implicate temporal lobe abnormalities in criminal psychopaths

Psychopathy is associated with abnormalities in attention and orienting. However, few studies have examined the neural systems underlying these processes. To address this issue, the authors recorded event-related potentials (ERPs) while 80 incarcerated men, classified as psychopathic or nonpsychopathic via the Hare Psychopathy Checklist--Revised (R. D. Hare, 1991, 2003), completed an auditory oddball task. Consistent with hypotheses, processing of targets elicited larger frontocentral negativities (N550) in psychopaths than in nonpsychopaths. Psychopaths also showed an enlarged N2 and reduced P3 during target detection. Similar ERP modulations have been reported in patients with amygdala and temporal lobe damage. The data are interpreted as supporting the hypothesis that psychopathy may be related to dysfunction of the paralimbic system--a system that includes parts of the temporal and frontal lobes.