A systematic review investigating a tolerance for pain and empathy for other people's pain in psychopathic traits within the general population

Psychopathic traits have been related to a higher tolerance for nociceptive pain and a deficit in empathy for others' pain. However, results are varied and inconsistent. As a result, this systematic review was conducted to consolidate findings. Reported in accordance with the PRISMA statement, a comprehensive literature search used 5 databases to identify articles published between 2000 and 2022 examining pain experience and empathy for others' pain in psychopathic traits (PROSPERO: CRD42023426112). From a total of 9522 articles, 8 papers were identified as eligible for inclusion. A total of 573 participants were included across 8 studies. Differences in pain tolerance to pressure and electric shocks were found in those higher in psychopathic traits, but not when using cold temperatures. In addition, higher levels of psychopathic traits related to less brain activity in response to others' pain, thus impacting empathy. This review highlights that within psychopathic traits, pain tolerance findings may be dependent upon the type of nociceptive pain stimulus and data collection method. Additionally, a lack of empathy for others may have a neurological basis. Lastly, boldness and meanness traits may play a specific tole in tolerating more nociceptive pain and lacking empathy for others.