In the first meta-analytic review of the response modulation hypothesis (RMH), an attention-based model for understanding the etiology of psychopathy, Smith and Lilienfeld (2015) report that the average effect size for response modulation deficits in psychopathic individuals fell in the small to medium range (r = .20; p. < .001, d = .41). Moreover, support for the RMH extended to both psychopathy dimensions, across diverse assessments and settings, and spanned child, adult, female, and male samples. The analysis also revealed good (...) empirical support for a central tenet of the RMH, namely that response modulation deficits are not limited to the processing of threat or other emotion stimuli. Unfortunately, the Smith and Lilienfeld meta-analysis contains several theoretical and quantitative problems, including failing to distinguish adequately between the tasks used to evaluate RMH predictions and the theory itself, confusion regarding the evolution of the RMH and its impact on effect sizes, misinterpretations of RMH predictions and evidence regarding dominant response sets, passive avoidance, and primary task performance, and biased statements promoting the low fear model over the RMH. In this response, we endeavor to reduce misunderstanding by addressing the most salient issues, with the hope that increasing clarity will sharpen the focus of future research and result in more valid assessments of the RMH. (shrink)

Psychopathy is a personality disorder characterized by interpersonal manipulation and callousness, and reckless and impulsive antisocial behavior. It is often seen as a disorder in which profound emotional disturbances lead to antisocial behavior. A lack of fear in particular has been proposed as an etiologically salient factor. In this review, we employ a conceptual model in which fear is parsed into separate subcomponents. Important historical conceptualizations of psychopathy, the neuroscientific and empirical evidence for fear deficits in psychopathy are compared against (...) this model. The empirical evidence is also subjected to a meta-analysis. We conclude that most studies have used the term "fear" generically, amassing different methods and levels of measurement under the umbrella term "fear." Unlike earlier claims that psychopathy is related to general fearlessness, we show there is evidence that psychopathic individuals have deficits in threat detection and responsivity, but that the evidence for reduced subjective experience of fear in psychopathy is far less compelling. (shrink)