J Psychiatry Neurosci 2012;35(6):390-8
Dustin A. Pardini, PhD; Mary Phillips, MD
From the Department of Psychiatry, University of Pittsburgh Medical Center, Pittsburgh, Pa.
Background: Abnormal neural responses to others’ emotions, particularly cues of threat and distress, have been implicated in the development of chronic violence. We examined neural responses to several emotional cues within a prospectively identified group of chronically violent men. We also explored the association between neural responses to social emotions and psychopathic features.
Methods: We compared neural responses to happy, sad, angry, fearful and neutral faces between chronically violent (n = 22) and nonviolent (n = 20) men using functional magnetic resonance imaging (fMRI). Participants were prospectively identified from a longitudinal study based on information collected from age 7 to 27 years. We assessed psychopathic features using a self-report measure administered in adulthood.
Results: The chronically violent men exhibited significantly reduced neural responses in the dorsomedial prefrontal cortex to all faces, regardless of the emotional content, compared with nonviolent men. We also observed a hyperactive amygdala response to neutral faces in chronically violent men, but only within the context of viewing happy faces. Moreover, they exhibited a greater dorsomedial prefrontal cortex response to mildly fearful faces than nonviolent men. These abnormalities were not associated with psychopathic features in chronically violent men.
Limitations: It remains unclear whether the observed neural abnormalities preceded or are a consequence of persistent violence, and these results may not generalize to chronically violent women.
Conclusion: Chronically violent men exhibit a reduced neural response to facial cues regardless of emotional content. It appears that chronically violent men may view emotionally ambiguous facial cues as potentially threatening and implicitly reinterpret subtle cues of fear in others so they no longer elicit a negative response.
Submitted Feb. 25, 2010; Revised May 11, 2010; Accepted May 11, 2010.
Acknowledgments: Neuroimaging data collection was supported by grants awarded to Dr. Pardini from the National Institute on Mental Health (1K01MH078039–01A1), Centers for Disease Control and Prevention (R49/CCR323155) through the National Center for Injury Prevention, and National Science Foundation (SES-0215551) through the National Consortium on Violence Research. The larger PYS study was supported by grants awarded to Dr. Rolf Loeber from the National Institute on Drug Abuse (DA411018), National Institute on Mental Health (MH 48890, MH 50778) and the Office of Juvenile Justice and Delinquency Prevention (96-MU-FX-0012). Any opinions, findings, conclusions or recommendations expressed in this paper are those of the authors and do not necessarily reflect the views of the National Science Foundation. Special thanks to Rolf Loeber, Magda Stouthamer-Loeber and to the PYS participants for their assistance on this project.
Competing interests: See above for Dr. Pardini. None declared for Dr. Phillips.
Contributors: Drs. Pardini and Phillips both designed the study, analyzed the data, reviewed the written article and approved its publication. Dr. Pardini acquired the data and wrote the article.
Correspondence to: Dr. D.A. Pardini, Sterling Plaza, Ste. 408, 201 N Craig St., Pittsburgh PA 15213; firstname.lastname@example.org