A special lockdown bonus with Kayla and special guest, her sister Alexis. We discuss the mystical MacDonald Triad, which many purport to be a predictor of violence, especially with serial killers. But is it accurate? Get your pitchforks out.

And stay healthy, please.

Sources:

• Grafman, J., Schwab, K., Warden, D., Pridgen, A., Brown, H. R., & Salazar, A. M. (1996). Frontal Lobe Injuries, Violence, and Aggression: A Report of the Vietnam Head Injury Study. Neurology, 46(5), 1231–1231. https://doi.org/10.1212/WNL.46.5.1231
• Leary, T., Southard, L., Hill, J., & Ashman, J. (2017). The Macdonald Triad Revisited: An Empirical Assessment of Relationships between Triadic Elements and Parental Abuse in Serial Killers. North American Journal of Psychology, 19(3), 627.
• Macdonald, J. M. (1963). The threat to kill. American Journal of Psychiatry, 120(2), 125–130. https://doi.org/10.1176/ajp.120.2.125
• Parfitt, C. H., & Alleyne, E. (2018). Not the sum of its parts: A critical review of the macdonald triad. Trauma, Violence, & Abuse, 1524838018764164. https://doi.org/10.1177/1524838018764164

  Ramsland, K. (2012). Triad of Evil. Psychology Today. http://www.psychologytoday.com/blog/shadow-boxing/201203/triad-evil
• Yarnell, H. (1940). Firesetting in children. American Journal of Orthopsychiatry, 10(2), 272–286. https://doi.org/10.1111/j.1939-0025.1940.tb05690.x

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