|Vol. 1, No. 1-2 , 1995, Page 6|
You're climbing into bed when you see a huge spider on the covers.
You're taking a shower alone when you hear someone breaking into your house.
You're in the dentist's office, waiting for a root canal.
Just reading those sentences causes your heart rate, skin conductance levels, and facial expression to change subtly. But a recent study found that psychopathic criminals-those who act impulsively without regard for consequences, and without empathy for their victims-react very differently.
Christopher Patrick et al. assigned 54 prisoners to low- and high-psychopathology groups based on a psychopathology checklist. They then recorded their skin, cardiac and facial responses to "fear imagery" sentences, like those above, and to neutral sentences.
The psychopaths, the researchers found, showed much smaller heart-rate and skin-conductance changes in response to the fear-provoking sentences than non-psychopathic subjects-indicating that the normal processes in which words prompt emotions is defective in psychopathic criminals. Facial responses also were smaller in the psychopathic group, although the difference was not significant.
Interestingly, the researchers note, the psychopaths reported having the same responses upon hearing the fear-imagery sentences as did non-psychopaths-even though the tests showed that they were reacting differently. The researchers say this indicates that nonaffective memory operations are intact in these individuals. This is consistent, they say, with the "mask of sanity" psychopaths present to the world.
Patrick et al. say the psychopath's inability to respond in a normal manner to fearful imagery "helps to account for the reckless, impulsive lifestyles of psychopaths," and also "helps to explain why verbally oriented approaches to treatment, which rely on language-affect connections, are so notoriously ineffective with this population."
Patrick et al.'s research strongly supports an earlier prospective study by Adrian Raine and colleagues. In the late 1970s, Raine et al. measured the resting heart rate, skin conductance and EEGs of 101 15-year-old male school children in England. When the subjects reached the age of 24, in 1988, the researchers ran computer searches to locate all who had been found guilty of crimes. They discovered that the subjects who later committed crimes "had a significantly lower resting heart rate, skin conductance activity, and more slow-frequency electroencephalographic activity than non-criminals." These differences were not related to social, demographic, or academic factors.
The researchers concluded that their findings "implicate under-arousal in all three response systems (electrodermal, cardiovascular, and cortical) in the development of criminality."
"Emotion in the criminal psychopath: fear image processing," Christopher Patrick, Bruce Cuthbert, and Peter Lang, Journal of Abnormal Psychology, Vol. 103, No. 3, 1994. Address: Christopher Patrick, Department of Psychology, Florida State University, Tallahassee, FL 32306-1051.
"Relationships between central and autonomic measures of arousal at age 15 years and criminality at age 24 years," Adrian Raine, Peter H. Venables, and Mark Williams, Archives of General Psychiatry, Vol. 47, November 1990. Address: Adrian Raine, Department of Psychology, S.G.M. Building, University of Southern California, Los Angeles, CA 90089-1061.