Sleep deprivation adversely affects interpersonal responses to frustration Ellen T. Kahn-Greene, Erica L. Lipizzi, Amy K. Conrad, Gary H. Kamimori, William D.S. Killgore * Division of Psychiatry and Neuroscience, Department of Behavioral Biology, Walter Reed Army Institute of Research (WRAIR), 503 Robert Grant Avenue, Silver Spring, MD 20910, United States Received 22 December 2005; received in revised form 25 April 2006 Available online 7 September 2006 Abstract Sleep deprivation produces negative effects on mood and cognitive function, but existing data have almost exclusively utilized objective rating scales, which do not permit evaluation of idiosyncratic and unstructured responses. In this study, we used a semi-projective measure, the Rosenzweig Picture-Frustra- tion (P-F) Study, to assess subjective responses to frustration following two nights without sleep. Twenty- six healthy volunteers completed the P-F at rested baseline and again following 55 h of continuous wakefulness. Participants provided written responses for an ambiguous cartoon character confronted with various frustrating situations. Relative to rested baseline, sleep deprivation was associated with altered responses on several indices, indicating a great number of uncommon types of responses, increased ten- dency to blame others for problems, and a reduced willingness to alleviate a conflict situation by accepting blame. Individual differences in several aspects of emotional intelligence were predictive of the extent to which responses to frustration changed with sleep loss. These findings suggest that sleep deprivation signif- icantly weakens the inhibition of aggression and willingness to behave in ways that facilitate effective social interaction, possibly through reduced metabolic activity in prefrontal regions of the brain important for personality, affect, and inhibitory behavior. Ó 2006 Elsevier Ltd. All rights reserved. 0191-8869/$ - see front matter Ó 2006 Elsevier Ltd. All rights reserved. doi:10.1016/j.paid.2006.06.002 * Corresponding author. Tel.: +1 301 319 9391; fax: +1 301 319 9979. E-mail address: william.killgore@na.amedd.army.mil (W.D.S. Killgore). www.elsevier.com/locate/paid Personality and Individual Differences 41 (2006) 1433–1443