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LIVING FOR `NOW'
Now-oriented thinking-making decisions with no regard to their consequences-is a hallmark of
criminals, who kill on impulse or steal "just for the fun of it." New research by Antoine Bechara et
al. shows that now-oriented thinking also is a common symptom of people with injuries to a
specific area of the prefrontal cortex.
The researchers designed a card-selecting task that required subjects to weigh long-term risks and
benefits. Control subjects found the task easy, but subjects with damage to the ventromedial
prefrontal cortex made card choices with "high immediate reward, but severe delayed punishment."
Their performance, the researchers say, is "comparable to their real-life inability to decide
advantageously, especially in personal and social matters [in which] an exact calculation of the
future outcomes is not possible and choices must be based on approximations." The researchers
found that their subjects "are generally insensitive to future consequences, positive or negative, and
thus their behavior is always guided by immediate prospects, whatever they may be."
Antonio Damasio, who participated in the research project, suggests that people with prefrontal
cortex damage can form mental representations of future outcomes, but that these are not "marked"
with a negative or positive value. He suspects that "developmental" sociopaths-those whose
problem behavior starts very early in life, and does not result from known injury or illness-may
have a similar defect.
The symptoms of "developmental" sociopaths are more severe than those of people with prefrontal
cortex injury; this makes sense, Damasio says, because the second group has benefited from years
of normal development.
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"Insensitivity to future consequences following damage to human prefrontal cortex," Antoine
Bechara, Antonio Damasio, Hanna Damasio, and Steven W. Anderson, Cognition, 50:7, 1994.
Address: Antonio Damasio, Department of Neurology, University of Iowa Hospitals and Clinics,
Iowa City, IA 52242.
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