Bad behaviour in childhood can predict both mental- and physical-health problems later in life. Among children with behaviour problems those with so-called callous-unemotional traits are a particular cause for concern. They show a lack of guilt and empathy for other people similar to that shown by adult psychopaths and tests have shown that they have difficulty recognising fear and sadness in others. Similar problems have been found among neuropsychological patients with damage to a part of the brain called the amygdala leading to suggestions that problems in this area could also exist in children with conduct problems. A brain-scan study of 30 boys - average age 11 - by researchers at the Institute of Psychiatry in London showed them pictures of fearful and neutral faces. Those boys with conduct problems and a higher level of callous-unemotional traits had less activity in the right amygdala when shown the fearful faces.
Jones, Alice P. ... [et al] - Amygdala hypoactivity to fearful faces in boys with conduct problems and callous-unemotional traits American Journal of Psychiatry January 2009, 166(1), 95-102