When a group of genetically identical mice lived in the same complex enclosure for 3 months, individuals that explored the environment more broadly grew more new neurons than less adventurous mice, according to a study published today (May 9) in Science. This link between exploratory behavior and adult neurogenesis shows that brain plasticity can be shaped by experience and suggests that the process may promote individuality, even among genetically identical organisms.
“This is a clear and quantitative demonstration that individual differences in behavior can be reflected in individual differences in brain plasticity,” said Fred Gage of the Salk Institute for Biological Studies in La Jolla, California, who was not involved the study. “I don’t know of another clear example of that . . . and it tells me that there is a tighter relationship between [individual] experiences and neurogenesis than we had previously thought.”
Scientists have often tried to tackle the question of how individual differences in behavior and personality develop in terms of the interactions between genes and environment. “But there is next to nothing [known] about the neurobiological mechanisms underlying individuality,” said Gerd Kempermann of the German Center for Neurodegenerative Diseases in Dresden….