Life Long Learning and Experiences are Good for the Brain

Rewiring in the brain is life-long

A new study from the Max Planck Institute overturns decades-old beliefs that most of the brain is hard-wired when one is a young adult. Working with older rats, neuroscientists were able to demonstrate rewiring of the brain by changing the nature of the sensory experience, suggesting that to stop learning may result in a substantial amount of lost brain connections.

Despite a long-held scientific belief that much of the wiring of the brain is fixed by the time of adolescence, a new study shows that changes in sensory experience can cause massive rewiring of the brain, even as one ages. In addition, the study found that this rewiring involves fibers that supply the primary input to the cerebral cortex, the part of the brain that is responsible for sensory perception, motor control and cognition. These findings promise to open new avenues of research on brain remodeling and aging.

“This study overturns decades-old beliefs that most of the brain is hard-wired before a critical period that ends when one is a young adult,” said MPFI neuroscientist Marcel Oberlaender, PhD, first author on the paper. “By changing the nature of sensory experience, we were able to demonstrate that the brain can rewire, even at an advanced age. This may suggest that if one stops learning and experiencing new things as one ages, a substantial amount of connections within the brain may be lost.”

The researchers conducted their study by examining the brains of older rats, focusing on an area of the brain known as the thalamus, which processes and delivers information obtained from sensory organs to the cerebral cortex. Connections between the thalamus and the cortex have been thought to stop changing by early adulthood, but this was not found to be the case in the rodents studied.

Being nocturnal animals, rats mainly rely on their whiskers as active sensory organs to explore and navigate their environment. For this reason, the whisker system is an ideal model for studying whether the brain can be remodeled by changing sensory experience. By simply trimming the whiskers, and preventing the rats from receiving this important and frequent form of sensory input, the scientists sought to determine whether extensive rewiring of the connections between the thalamus and cortex would occur.

On examination, they found that the animals with trimmed whiskers had altered axons, nerve fibers along which information is conveyed from one neuron (nerve cell) to many others; those whose whiskers were not trimmed had no axonal changes. Their findings were particularly striking as the rats were considered relatively old – meaning that this rewiring can still take place at an age not previously thought possible. Also notable was that the rewiring happened rapidly – in as little as a few days.

“We’ve shown that the structure of the rodent brain is in constant flux, and that this rewiring is shaped by sensory experience and interaction with the environment,” said Oberlaender. “These changes seem to be life-long and may pertain to other sensory systems and species, including people. Our findings open the possibility of new avenues of research on development of the aging brain using quantitative anatomical studies combined with noninvasive imaging technologies suitable for humans, such as functional MRI (fMRI).”

The study was possible due to recent advances in high-resolution imaging and reconstruction techniques, developed in part by Oberlaender at MPFI. These novel methods enable researchers to automatically and reliably trace the fine and complex branching patterns of individual axons, with typical diameters less than a thousandth of a millimeter, throughout the entire brain.

Oberlaender is part of the Max Planck Florida Institute’s Digital Neuroanatomy group, led by Nobel laureate Bert Sakmann. The group focuses on the functional anatomy of circuits in the cerebral cortex that form the basis of simple behaviors (e.g. decision making). One of the group’s most significant efforts is a program dedicated to obtaining a three-dimensional map of the rodent brain. This work will provide insight into the functional architecture of entire cortical areas, and will lay the foundation for a mechanistic understanding of sensory perception and behavior.

Source: Max Planck Institute

Image: Human Brain from Shutterstock

1 Comment on "Life Long Learning and Experiences are Good for the Brain"

  1. Madanagopal.V.C. | October 17, 2012 at 12:06 pm | Reply

    Rewiring of the neurons of the brain is continuous in the sense that man keeps on learning till his death. Learning is not only confined to reading books and science but everyday`s experience is also a learning process. Whether a man is literate or illiterate, he keeps on learning in some spheres. The hard disk of the brain is more than a billion terabytes in capacity. Only thing needed is to make copy of the file of every day`s learning in permanent connections of neurons growth. We should note that brain`s neurons growth is possible throughout life but once the brain cell dies it cannot be regenerated, like all other cells of the body. Otherwise, every 40 days one should keep on reading alphabets of his nursery classes repeatedly, because the neurons would perish and regenerate in the brain like other cells where programmed cell death is a boon to get new tissues periodically in skin , blood ,hair etc. Life long learning new things everyday for generating new neurons is good to beat Alzheimer`s disease in later years. The article gives a sound proof for life long learning to be beneficial for the brain. Thank YOu.

Leave a comment

Your email address will not be published.


*