The psychopathic brain

A very interesting article by Dr Karl Kruszelnicki revealed that psychopathology, characterised by features such as egocentricity, a lack of empathy, remorse and poor impulse control, may be associated with the orbito-frontal cortex in the human brain. The orbito-frontal cortex (OFC) is located in the pre-frontal area of the frontal lobes behind the eyes, as indicated by the green shading on the image to the right.

The OFC controls those behaviours which are known to be impaired in psychopaths, including impulse control, planning and calculating risk. It also has a role in processing odours, and research has shown that psychopaths have a poor sense of smell.

Shamay-Tsoory, Harari, Aharon-Peretz, and Levkovitz (2010) proposed that psychopathy is associated with impairments in theory of mind (TOM) which is also associated with the OFC. TOM is the ability to understand what another person may be thinking and feeling, and to be able to appreciate their perspective. Shamay-Tsoory et al. showed that people with lesions in the OFC performed poorly on complex TOM tasks, particularly those drawing on affective TOM, which involves interpreting emotions. People with psychopathic tendencies had similar difficulties on complex TOM tasks as those individuals with lesions in the OFC.

The authors suggested that psychopaths may not appreciate the emotions, fears and sorrow of other people, which allows them to behave callously without feelings of remorse.

The OFC also has extensive projections to a part of the brain called the amygdala. The amygdala is involved in processing fearful and sad facial expressions and emotions and has a role in instrumental learning. Several neuroimaging studies have shown that people with psychopathic tendencies have reduced amygdala volume (Kiehl et al., 2001; Tiihonen et al., 2000).

References

Kiehl, K.A., Smith, A.M., Hare, R.D., et al. (2001). Limbic abnormalities in affective processing by criminal psychopaths as revealed by functional magnetic resonance imaging. Biological Psychiatry, 50, 677-684.

Shamay-Tsoory, S. G., Harari, H., Aharon-Peretz, J., & Levkovitz, Y. (2010). The role of the orbitofrontal cortex in affective theory of mind in criminal offenders with psychopathic tendencies. Cortex, 46, 668-677.

Tiihonen, J., Hodgins, S., Vaurio, O., et al. (2000). Amygdaloid volume loss in psychopathy. Society for Neuroscience Abstracts, 2017.