快猫短视频

THE brain can鈥檛 compensate for damage to the frontal lobe during childhood.
Because such damage can stop children learning moral rules, the finding may shed
light on why people become psychopathic.

Antonio Damasio and his colleagues at the University of Iowa studied a
20-year-old woman and a 23-year-old man whose frontal lobes were damaged when
they were infants. Like many patients who suffer the same damage in adulthood,
they scored normally on intelligence tests, but showed impaired social
behaviour.

The two patients often lied, stole and assaulted others, and showed little
remorse. But unlike patients who sustain similar damage as adults, they reasoned
about social dilemmas as simplistically as 10-year-olds. 鈥淎dult-onset patients
operate inappropriately, but they know the rules,鈥� says Damasio. 鈥淭hese
early-onset patients never learnt the rules.鈥�

The finding suggests the damage prevented the patients learning moral
reasoning as children. This is surprising, as the brain often compensates for
injuries in childhood. If there鈥檚 damage to regions that handle language, for
instance, other parts of the brain may take over their role.

The study also hints that there might be a physical basis for psychopathy.
Both the brain-damaged subjects behaved in many ways like adult psychopaths. In
particular, they showed no physical signs of anxiety when they were about to
make a risky response and didn鈥檛 learn from experience.

Raymond Dolan, a neuropsychiatrist at University College London, welcomes the
study. 鈥淚t鈥檚 putting problems at the heart of interpersonal behaviour into the
realm of neuroscience.鈥�