Contagious yawning in African painted dogs

Animal Cognition - Contagious yawning (CY), which is yawning elicited by sensing another yawning, has been observed only in social species and is considered linked to high sociality. Although this...     

Contagious yawning in domestic dog puppies (Canis lupus familiaris): the effect of ontogeny and emotional closeness on low-level imitation in dogs

Contagious yawning is a well-documented phenomenon in humans and has recently attracted much attention from developmental and comparative sciences. The function, development and underlying mechanisms of the phenomenon, however, remain largely unclear. Contagious yawning has been demonstrated in dogs and several non-human primate species, and theoretically and empirically associated with empathy in humans and non-human primates. Evidence of emotional closeness modulating contagious yawning in dogs has, nonetheless, been contradictory. Humans show a developmental increase in susceptibility to yawn contagion, with typically developing children displaying a substantial increase at the age of four, when a number of cognitive abilities (e.g. accurate identification of others’ emotions) begin to clearly manifest. Explicit tests of yawn contagion in non-human animals have, however, thus far only involved adult individuals. Here, we report a study of the ontogeny of domestic dogs’ (Canis lupus familiaris) susceptibility to yawn contagion, and whether emotional closeness to the yawning model affects this. Thirty-five dogs, aged 4–14 months, observed a familiar and unfamiliar human repeatedly yawn or gape. The dogs yawned contagiously, but emotional closeness with the model did not affect the strength of contagion, raising questions as to recent evidence of emotionally modulated auditory contagious yawning in dogs. The dogs showed a developmental effect, with only dogs above 7 months evidencing contagion. The results support the notion of a developmental increase in dogs’ attention to others and identification of others’ emotional states and suggest that yawn contagion is underpinned by developmental processes shared by humans and other animals.     

On yawning and its functions

The forms and behavioral correlates of yawning are described, and the phylogenetic and ontogenetic aspects of the act are examined with particular attention to its possible functions. Much evidence supports the view that yawning is an important mediator of behavioral arousal levels, a view that is further strengthened by a review of endocrine, neurotransmitter, and pharmacological mechanisms of yawning: A major function of yawning appears to involve maintenance or increase of arousal when environments provide relatively little stimulation.     

Emotional deficiency and psychopathy

Aside from an antisocial life-style, the concept of psychopathy is based on character features which can be described in terms of specific patterns of interpersonal, behavioral, and, in particular, affective characteristics. Concluding from studies which have dealt with the affective domain in psychopaths, emotional deficiency may predispose to violence in several ways. (1) Poor conditioning implicates a failure to review the harmful consequences of one's actions leading to a deficit of avoidance behavior. (2) Emotional detachment prevents experiencing feelings, which naturally inhibit the acting out of violent impulses. (3) Emotional deficiency is closely associated with a general underarousal, leading to sensation seeking. Current data suggest that there may be a close association between difficulties in emotional processing and poor prefrontal functioning. From a psychosocial perspective, psychopaths were shown to have been exposed to severe familial and societal difficulties. Whether biological or environmental factors dominate in the etiology of this personality disorder, psychopathy does not per se justify the assumption of decreased legal responsibility.     

Contagious Disease and Self-Defence

This paper gives a self-defence account of the scope and limits of the justified use of compulsion to control contagious disease. It applies an individualistic model of self-defence for state action and uses it to illuminate the constraints on public health compulsion of proportionality and using the least restrictive alternative. It next shows how a self-defence account should not be rejected on the basis of past abuses. The paper then considers two possible limits to a self-defence justification: compulsion of the non-culpable and over-inclusive compulsion. The paper claims that objections to compelling the non-culpable do not greatly restrict the scope of the self-defence justification. The over-included are, however, innocent bystanders, and methods such as compulsory quarantine, vaccination, and screening are not justified in self-defence. I am grateful to Julian Lamont, Jeff McMahan and Debbie Tseung for their help with this paper. An earlier version was given at the School of Public Health, the University of Texas at Houston; the Auckland Regional Public Health Service; and a conference at the School of Population Health, the University of Auckland. My thanks to the audiences for their comments.     

Longitudinal evidence that psychopathy scores in early adolescence predict adult psychopathy

This study examined the relation between psychopathy assessed at age 13 by using the mother-reported Childhood Psychopathy Scale (D. R. Lynam, 1997) and psychopathy assessed at age 24 by using the interviewer-rated Psychopathy Checklist: Screening Version (PCL:SV; S. D. Hart, D. N. Cox, & R. D. Hare, 1995). Data from over 250 participants of the middle sample of the Pittsburgh Youth Study were used to examine this relation; approximately 9% of the sample met criteria for a possible PCL:SV diagnosis. Despite the long time lag, different sources, and different methods, psychopathy from early adolescence into young adulthood was moderately stable (r=.31). The relation was present for the PCL:SV total and facet scores, was not moderated by initial risk status or initial psychopathy level, and held even after controlling for other age 13 variables. Diagnostic stability was somewhat lower. Both specificity and negative predictive power were good, and sensitivity was adequate, but positive predictive power was poor. This constitutes the first demonstration of the relative stability of psychopathy from adolescence into adulthood and provides evidence for the incremental utility of the adolescent psychopathy construct. Implications and future directions are discussed.     

Treatment and psychopathy in forensic settings

People commonly question whether highly psychopathic offenders are treatable. Little scientific research has addressed this question despite key developments in the last 20 years in two relevant areas: reliable measurement of psychopathy, and effective treatments for reducing criminal and antisocial behavior in offenders. One obstacle to progress is confusion about defining psychopathy; a necessary preliminary step to advancing intervention. After outlining the principal definitional issues, we review past and recent research on psychopathy and treatment, concluding that a handful of newer, well-designed studies suggest grounds for optimism about psychopathy and treatability. Although psychopathy characteristics—along with other indices of criminal risk—signal responsivity challenges, well-conceived programs for higher risk offenders can reduce recidivism in highly psychopathic offenders and appear to do so by reducing dynamic risk factors. There are no clear indications yet of whether PCL-psychopathic offenders differ from other high-risk offenders in their ability to respond to such treatments. The questions of whether psychopathy itself responds to treatment, and if so, what forms such treatment might take have not yet been addressed. We conclude by suggesting that advances will come from the use of more divergent measures of psychopathy, and in particular, dynamic measures of psychopathy traits that will allow us to document whether change is occurring.     

An investigation of auditory contagious yawning

Despite a widespread familiarity with the often compelling urge to yawn after perceiving someone else yawn, an understanding of the neural mechanism underlying contagious yawning remains incomplete. In the present auditory fMRI study, listeners used a 4-point scale to indicate how much they felt like yawning following the presentation of a yawn, breath, or scrambled yawn sound. Not only were yawn sounds given significantly higher ratings, a trait positively correlated with each individual’s empathy measure, but relative to control stimuli, random effects analyses revealed enhanced hemodynamic activity in the right posterior inferior frontal gyrus (pIFG) in response to hearing yawns. Moreover, pIFG activity was greatest for yawn stimuli associated with high as opposed to low yawn ratings and for control sounds associated with equally high yawn ratings. These results support a relationship between contagious yawning and empathy and provide evidence for pIFG involvement in contagious yawning. A supplemental figure for this study may be downloaded from http://cabn.psychonomic-journals.org/content/supplemental.     

The Millon adolescent clinical inventory and psychopathy

We investigated the ability of the Millon Adolescent Clinical Inventory (MACI; Millon, 1993) to assess psychopathy as measured by the Psychopathy Checklist--Revised (PCL-R; Hare, 1991). Participants were 90 adolescents in an inpatient psychiatric unit. The MACI Substance Abuse Proneness (r = .47), Unruly (r = .43), and Submissive (r = -.42) scales correlated most strongly with the PCL-R. Using a discriminant function analysis, the Substance Abuse Proneness scale correctly distinguished between high- and low-psychopathy groups in 79% of cases. Using a rational approach, we developed a psychopathy content scale using 20 MACI items. This content scale correlated with the PCL-R (r = .60) and distinguished high- and low-psychopathy groups in 83% (kappa = .66) of cases (sensitivity = 85%, specificity = 81%).     

Moral cognition,affect, and psychopathy

Few theorists would challenge the idea that affect and emotion directly influence decision-making and moral judgment. There is good reason to think that they also significantly assist in decision-making and judgment, and in fact are necessary for fully effective moral cognition. However, they are not sufficient. Deliberation and more reflective thought processes likewise play a crucial role, and in fact are inseparable from affective processes. I will argue that while the dual-process account of moral judgment set forth by Craigie (2011) has great merit, it fails to appreciate fully the extent to which affective and reflective processes are not only integrated, but also mutually interdependent. Evidence from psychopathy indicates that when reflective processes are not assisted adequately by what I will call ‘affective framing’, and moral cognition is of the “cooler,” less emotionally-informed variety, what results is not effective cognitive functioning, but rather psychopathology. My proposed account of affective framing aims to make sense of the way in which affect plays a strictly necessary and integral role not just in intuitive moral responses, but also in reflective moral judgments, so that moral cognition is accomplished by the joint operation of affective processes and reflective reasoning processes.     

Increased testosterone-to-cortisol ratio in psychopathy

Only a few studies have examined hormones in psychopathy, and results have been mixed. It has been suggested that because hormone systems are highly interconnected, it may be important to examine multiple systems simultaneously to gain a clearer picture of how hormones work together to predispose for a certain construct. In the present study, we attempt to clarify the role of the hormones cortisol and testosterone in psychopathy by examining both hormones in a community sample of 178 adults demonstrating a wide range of psychopathy scores. Results showed that psychopathy scores were associated with an increased ratio of testosterone (baseline) to cortisol responsivity to a stressor. Psychopathy was not associated with either of these measures independently or with baseline cortisol levels. These findings suggest that these highly interconnected hormone systems may work in concert to predispose to psychopathy.     

No evidence for contagious yawning in lemurs

Among some haplorhine primates, including humans, relaxed yawns spread contagiously. Such contagious yawning has been linked to social bonds and empathy in some species. However, no studies have investigated contagious yawning in strepsirhines. We conducted an experimental study of contagious yawning in strepsirhines, testing ring-tailed and ruffed lemurs (n = 24) in a paradigm similar to one that has induced contagious yawning in haplorhines. First, in a control experiment, we investigated whether lemurs responded to projected video content in general (experiment 1). We showed them two videos to which we expected differential responses: one featured a terrestrial predator and the other a caretaker holding food. Next, to test for yawn contagion, we showed individual lemurs life-size video projections of groupmates and conspecific strangers yawning, and control footage of the same individuals at rest (experiment 2). Then, to examine whether a group context might enhance or allow for contagion, we exposed subjects to the same videos in a group setting (experiment 3). Lemurs produced alarm vocalizations and moved upward while viewing the predator, but not the caretaker, demonstrating that they do perceive video content meaningfully. However, lemurs did not yawn in response to yawning stimuli when tested alone, or with their groupmates. This study provides preliminary evidence that lemurs do not respond to yawning stimuli similarly to haplorhines, and suggests that this behavior may have evolved or become more exaggerated in haplorhines after the two major primate lineages split.     

Secondary psychopathy,but not primary psychopathy,is associated with risky decision-making in noninstitutionalized young adults

Although risky decision-making has been posited to contribute to the maladaptive behavior of individuals with psychopathic tendencies, the performance of psychopathic groups on a common task of risky decision-making, the Iowa Gambling Task (IGT; Bechara, Damasio, Damasio, & Anderson, 1994), has been equivocal. Different aspects of psychopathy (personality traits, antisocial deviance) and/or moderating variables may help to explain these inconsistent findings. In a sample of college students (N = 129, age 18–27), we examined the relationship between primary and secondary psychopathic features and IGT performance. A measure of impulsivity was included to investigate its potential as a moderator. In a joint model including main effects and interactions between primary psychopathy, secondary psychopathy and impulsivity, only secondary psychopathy was significantly related to risky IGT performance, and this effect was not moderated by the other variables. This finding supports the growing literature suggesting that secondary psychopathy is a better predictor of decision-making problems than the primary psychopathic personality traits of lack of empathy and remorselessness.