Short answers, pulled from the story.
Hervey M. Cleckley published The Mask of Sanity in 1941. This monograph fundamentally reshaped how psychiatry understood dangerous personalities by describing patients who appeared charming and emotionally stable yet systematically destroyed lives without feeling guilt. Cleckley formulated sixteen criteria for this condition based on his observations at a Veterans Administration hospital in Georgia.
The average score on the Psychopathy Checklist-Revised for North American prisoner samples is 22.1. Approximately 20.5% of inmates score 30 or higher, which is a threshold often used to designate a psychopath. This checklist measures interpersonal-affective traits and antisocial behaviors to assess the presence of psychopathic traits in incarcerated offenders.
The amygdala is approximately 18% smaller in individuals with psychopathy. This region is critical for processing fear and sadness, and its reduced size contributes to the individual's reduced emotional sensation and impaired empathy. Damage to the ventromedial prefrontal cortex also regulates activity in the amygdala, leading to common characteristics observed in psychopathic individuals.
The Antisocial Process Screening Device can be administered to individuals aged 6 to 13. This tool is an adaptation of the Psychopathy Checklist-Revised and can be used by parents or teachers for early identification of psychopathic traits. Research indicates that children with conduct disorder who display callous-unemotional traits tend to have a more severe form of the disorder with an earlier onset.
Only 11 percent of violent females in prison met the psychopathy criteria compared to 31 percent of violent males. Men score higher than women on both the Psychopathy Checklist-Revised and the Psychopathic Personality Inventory. Studies suggest that for girls, 75% of the variance in severe callous and unemotional traits is attributable to environmental factors, while genetic factors play a more significant role for boys.
No pharmacological therapies are known to alleviate the emotional, interpersonal, and moral deficits of the disorder. Attempts to treat psychopathy with existing tools have been largely ineffective, and patients are generally unmotivated to seek treatment. The management of antisocial and criminal behavior remains the main aim of therapy programs in correctional settings.