How the Brain Learns from Mistakes

Learning from mistakes may be, in part, a matter of
genetics.

New research shows that a certain gene glitch may make it harder to learn
from negative feedback.

That gene glitch affects the number of receptors for the brain chemical
dopamine.

Dopamine parks at dopamine receptors to do its job.  Having fewer
dopamine receptors is like having fewer parking spots at work -- you can't do
your job if you're circling, looking for a parking spot.

German researchers studied 26 healthy men, some of whom had the dopamine
receptor gene mutation.

The men -- who were about 27 years old, on average -- watched the letter
pairs AB, CD, and EF appear on the screen.

The men picked one letter from each letter pair. Choosing A, C, or E, made a
smiley face pop onto the computer screen. A scowling face appeared on the
computer screen if they picked B, D, or F.

Next, the men saw new letter pairs. They picked a letter from each pair and
got more feedback reinforcing or discouraging their choices.

Men with fewer dopamine receptors were less responsive than the other men to
negative feedback. But all of the men were good at learning from positive
feedback.

The findings may shed new light on the link between fewer dopamine receptors
and risky habits such as addiction and compulsive
gambling, write the researchers.

They included graduate student Tilmann Klein of the Max Planck Institute for
Human Cognitive and Brain Sciences in Leipzig, Germany.

Klein's team doesn't note any addictions in the men who participated in the
study, which appears in tomorrow's edition of Science.

By Miranda Hitti
Reviewed by Brunilda Nazario
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