This is the first study to demonstrate reduced amygdala responsiveness in youths with callous-unemotional traits. These findings support the contention that callous and unemotional personality traits are associated with reduced amygdala response to distress-based social cues.

Individuals with disorders marked by antisocial behavior frequently show deficits in recognizing displays of facial affect. Antisociality may be associated with specific deficits in identifying fearful expressions, which would implicate dysfunction in neural structures that subserve fearful expression processing. A meta-analysis of 20 studies was conducted to assess: (a) if antisocial populations show any consistent deficits in recognizing six emotional expressions; (b) beyond any generalized impairment, whether specific fear recognition deficits are apparent; and (c) if deficits in fear recognition are a function of task difficulty. Results show a robust link between antisocial behavior and specific deficits in recognizing fearful expressions. This impairment cannot be attributed solely to task difficulty. These results suggest dysfunction among antisocial individuals in specified neural substrates, namely the amygdala, involved in processing fearful facial affect. KeywordsFacial affect; fearful expression; antisocial; amygdala; psychopathy; emotion; meta-analysis Processing facial affect is crucial for socialization and normal social interaction (Corden et al. 2006;Fridlund, 1991). Aggression and other maladaptive antisocial behaviors may result from failure to be appropriately guided by the social cues of others (Blair, 2003a;Montagne et al. 2005;Walker and Leister, 1994). Some have suggested that distress-related cues, particularly fearful expressions, play an important role in inhibiting antisocial behavior (Blair, 2001;Nichols, 2001;Price, 2004). Accordingly, many studies find impairments in processing distress-related cues among antisocial populations. Not all studies find this impairment, however. It is unclear whether these inconsistencies result from disparate methodologies, sample populations, or analytic techniques, or, alternately, from the absence of a strong relationship between fearful affect processing and antisociality. Better understanding of facial affect recognition deficits associated with antisociality would permit more precise hypotheses to be formulated regarding neurocognitive correlates of antisocial behavior. We thus conducted this meta-analysis to assess associations between antisociality and facial affect recognition deficits. We hypothesized that, beyond any general facial affect recognition deficits, antisocial individuals show specific deficits in processing fearful expressions. We also hypothesized that such deficits are not solely attributable to task difficulty.*Address correspondence to: Abigail Marsh, Ph.D., Mood and Anxiety Program, National Institute of Mental Health, 15K North Drive, MSC 2670, Bethesda, MD, 20892. Email: marsha@mail.nih.gov; Tel: (301) Fax: (301) 402−6353. Publisher's Disclaimer: This is a PDF file of an unedited manuscript that has been accepted for publication. As a service to our customers we are providing this early version of the manuscript. The manuscript will undergo copyediting, typesetting, and review of the resulting proof before it ...

The facial expressions of fear and anger are universal social signals in humans. Both expressions have been frequently presumed to signify threat to perceivers and therefore are often used in studies investigating responses to threatening stimuli. Here the authors show that the anger expression facilitates avoidance-related behavior in participants, which supports the notion of this expression being a threatening stimulus. The fear expression, on the other hand, facilitates approach behaviors in perceivers. This contradicts the notion of the fear expression as predominantly threatening or aversive and suggests it may represent an affiliative stimulus. Although the fear expression may signal that a threat is present in the environment, the effect of the expression on conspecifics may be in part to elicit approach.

To our knowledge, this study provides the first evidence of abnormal ventromedial prefrontal cortex responsiveness in children with psychopathic traits and demonstrates this dysfunction was not attributable to comorbid attention-deficit/hyperactivity disorder. These findings suggest that reversal learning impairments in patients with developmental psychopathic traits relate to abnormal processing of reinforcement information.