Psychopathic personality in young people

This article is an overview of developments in psychopathy and their application to children and adolescents. A key question is whether or not psychopathy is stable throughout the lifespan. Some characteristics indicate phenotypic similarities with adult psychopathy, and current instruments appear to be measuring similar constructs across the age ranges. Although the literature on developmental aspects of psychopathy in young people is limited, a number of instruments have been designed to measure the construct. These tools appear to have reasonable construct, concurrent and predictive validity, but we cannot yet recommend their routine use in clinical practice or in the criminal justice system, given the limited evidence base on their predictive validity. At best, they should be viewed as a means of subtyping potentially high-risk groups with a view to treatment planning. Psychopathic personality in young people 467 Advances in Psychiatric Treatment (2004), vol. 10. http://apt.rcpsych.org/ particularly those with a history of repeated violent behaviour, exhibit neuropsychological deficits (Moffitt & Henry, 1991) and have reduced levels of arousal, including reduced plasma cortisol levels (Raine, 1993; McBurnett & Lahey, 1994). These findings suggest a role for neurobiological factors, particularly executive (prefrontal) and temporolimbic (amygdala) dysfunction, in the aetiology of conduct disorder and psychopathy. The prefrontal cortex and behaviour There are a number of theories relating to the neurological basis of antisocial behaviour and psychopathy. Of those focusing on the prefrontal cortex, the most prominent are the somatic marker hypothesis (Damasio, 1994) and the response modulation deficit hypothesis (for a review see Newman, 1998). The somatic marker hypothesis suggests that damage to the ventromedial cortex results in a failure of the somatosensory structures to mark experiences as good or bad, and consequently there is no mechanism for learning to avoid aversive situations. This model receives some support from studies of acquired psychopathy, where subjects show an attenuated autonomic response to aversive social stimuli. The response modulation deficit hypothesis, which also focuses on the ventromedial prefrontal cortex, accounts for the risk-taking behaviour and failure to learn from experience seen in criminals with psychopathic personality performing laboratory-based tasks of passive-avoidance learning. Some support for the response modulation deficit hypothesis comes from studies revealing that children with marked callous and unemotional traits show an insensitivity to punishment cues on a gambling task (Frick, 1998). The amygdala and affect There are also two main theories relating to the affective characteristics of psychopathy: the punishment/low-fear theory (Lykken, 1995) and the violence inhibition mechanism deficit hypothesis (Blair, 1995). Both models suggest a crucial role for the amygdala as the seat of dysfunction in psychopathic individuals. The low-fear model stresses the aspects of psychopathy related to sensation-seeking and insensitivity to punishment (Lykken, 1995; Patrick, 1994), whereas the violence inhibition mechanism model accounts for the specific failure of basic emotions (e.g. fear) to result in autonomic arousal and the inhibition of ongoing behaviour in individuals with psychopathic personality. To date, few of these theories have been extensively tested in child and adolescent samples. However, some support for the violence inhibition mechanism model has emerged in studies showing a selective impairment in the processing of sad and fearful faces in children with psychopathic tendencies (Blair et al, 2001). The relationship between callous-unemotional traits and conduct disorder Frick (1998) outlined a basic framework for conceptualising the relationship between what he termed callous-unemotional traits and conduct problems in children. In this model, callousunemotional traits develop as part of a unique temperamental style, low behavioural inhibition, which makes the child poorly responsive to socialisation. Kochanska (1993) suggested that behavioural inhibition is critical in the development of conscience in young children and reported that low-fear children did not respond to the type of socialisation (gentle, non-power, assertive discipline) that led to conscience development in more fearful children. Subsequent studies in children with conduct disorder indicated that the style parents use to socialise their child has less impact on the development of conduct problems in children with callous-unemotional traits, suggesting that genetic or neurodevelopmental factors make a more significant contribution in children who are notably callous. Psychopathy in children and adolescents The existence and assessment of psychopathy in children and adolescents is a contentious issue (Edens et al, 2001; Hart et al, 2002; Seagrave & Grisso, 2002). Key concerns centre on the reliability and validity of current assessment tools, the developmental appropriateness of these measures, how closely the construct mimics that in adulthood and the potentially negative impact of attaching a label of psychopathy to those who have not yet reached maturity (Box 1). Frick (2002) argues that psychopathy presents no more of a challenge than any other measure of psychopathology in children and adolescents, and suggests that psychopathy assessment in juveniles may be a means of early detection and intervention in high-risk groups.