Social Cognitive and Affective Neuroscience Advance Access published online on September 21, 2009
Social Cognitive and Affective Neuroscience, doi:10.1093/scan/nsp036
Developmental effects of aggressive behavior in male adolescents assessed with structural and functional brain imaging
1National Institute of Neurological Disorders and Stroke, Cognitive Neuroscience Section, 10 Center Drive, Bethesda MD 20892, USA, 2Institute of Psychology, Department of Cognitive Psychology, Humboldt University, Rudower Chaussee 18, 12489 Berlin, Germany, 3Brain Innovation, Postbus 1142, 6201 BC Maastricht, The Netherlands, and 4National Institute of Mental Health, Child Psychiatry Branch, 10 Center Drive, Bethesda, MD 20892, USA.
Aggressive behavior is common during adolescence. Although aggression-related functional changes in the ventromedial prefrontal cortex (vmPFC) and frontopolar cortex (FPC) have been reported in adults, the neural correlates of aggressive behavior in adolescents, particularly in the context of structural neurodevelopment, are obscure. We used functional and structural magnetic resonance imaging (MRI) to measure the blood oxygenation level-depended signal and cortical thickness. In a block-designed experiment, 14–17-year old adolescents imagined aggressive and non-aggressive interactions with a peer. We show reduced vmPFC activation associated with imagined aggressive behavior as well as enhanced aggression-related activation and cortical thinning in the FPC with increasing age. Changes in FPC activation were also associated with judgments of the severity of aggressive acts. Reduced vmPFC activation was associated with greater aggression indicating its normal function is to exert inhibitory control over aggressive impulses. Concurrent FPC activation likely reflects foresight of harmful consequences that result from aggressive acts. The correlation of age-dependent activation changes and cortical thinning demonstrates ongoing maturation of the FPC during adolescence towards a refinement of social and cognitive information processing that can potentially facilitate mature social behavior in aggressive contexts.
Keywords: ventromedial prefrontal cortex; frontopolar cortex; fMRI; cortical thickness; neurodevelopment; trait anger
Correspondence should be addressed to Jordan Grafman, Cognitive Neuroscience Section, National Institute of Neurological Disorders and Stroke, National Institutes of Health, 10 Center Drive, Building 10, Room 7D43, Bethesda, MD 20892, MSC1440, USA. E-mail: grafmanj{at}ninds.nih.gov
*These authors contributed equally to this work.
Received April 8, 2009. Accepted August 6, 2009.