Psychopathy

• people with antisocial personality disorder exhibit traits of impulsivity, high negative emotionality, low conscientiousness and associated behaviours including irresponsible and exploitative behaviour, recklessness and deceitfulness
  • manifest in unstable interpersonal relationships, disregard for the consequences of one's behaviour, a failure to learn from experience, egocentricity and a disregard for the feelings of others
  • many people with antisocial personality disorder have a criminal conviction and are imprisoned or die prematurely as a result of reckless behaviour
    • criminal behaviour is central to the definition of antisocial personality disorder, although it is often the culmination of previous and long-standing difficulties, such as socioeconomic, educational and family problems (1)
      • prevalence of antisocial personality disorder among prisoners is slightly less than 50%
      • estimated in epidemiological studies in the community that only 47% of people who meet the criteria for antisocial personality disorder have significant arrest records
      • prevalence of antisocial personality disorder in the general population is 3% in men and 1% in women
• psychopathy
  • in English-speaking countries the term psychopathy is generally used with the meaning of a persistent personality disorder that is characterised by anti-social conduct. People in this category are not mentally ill in the sense of being psychotic or neurotic, nor are they necessarily mentally subnormal, but they come into conflict with society because of abnormalities in their personality
    • people with psychopathy and people who meet criteria for dangerous and severe personality disorder (DSPD) represent a small proportion of people with antisocial personality disorder. However, they present a very high risk of harm to others and consume a significant proportion of the services for people with antisocial personality disorder (1)
  • such people may behave in ways regarded as unethical or criminal by the rest of society. As a result the term psychopath can be used with pejorative overtones, implying dislike or censure. For this and other reasons (such as lack of a widely agreed definition), some psychiatrists avoid using the term; others hold that the term can be usefully maintained if applied carefully and without prejudice

Notes:

• under current diagnostic systems, antisocial personality disorder is not formally diagnosed before the age of 18 but the features of the disorder can manifest earlier as conduct disorder. People with conduct disorder typically show antisocial, aggressive or defiant behaviour, which is persistent and repetitive, including aggression to people or animals, destruction of property, deceitfulness, theft and serious rule-breaking
• neuroimaging studies have shown the involvement in this pathological condition of prefrontal areas, especially orbitofrontal cortex, and amygdala in individual with antisocial personality disorder
  • also individuals exhibit alterations in measures of 5-HT system, such as blunted hormonal response to 5-HT pharmacological challenges and reduced 5-HT receptors numbers
  • there may be EEG abnormalities in individuals antisocial personality disorder
    • study evidence revealed EEG abnormalisties in 50% of violent offenders (2)
    • a more recent study revealed attenuated alpha rhythm and theta and delta activities increase in the frontal lobe in violent offenders with antisocial personality disorder (3)

Reference:

• 1. NICE (January 2009). Antisocial personality disorder - treatment and management
• 2. Bach-y-Rita G et al. Episodic dyscontrol: a study of 130 violent patients. Am J Psychiat 1971;127:473-1478.
• 3. Reyes AC, Amado AA. Qualitative and quantitative EEG abnormalities in violent offenders with antisocial personality disorder. Journal of Forensic and Legal Medicine 2009; 16 (2): 59-63