Nerve cells communicate through short, fleeting pulses of electrical activity. Yet some memories stored in the brain can persist for decades. Research into how the nervous system bridges these two radically different time scales has been going on for decades, and a number of different ideas have picked up some experimental support.
For instance, based on their past activity, nerve cells can dictate which partners they make contact with or increase or decrease the strength of those connections—in essence, rewiring the brain as it develops and processes experiences. In addition, individual cells can make long-term changes in the genes that are active, locking specific behaviors in place. In a paper released by Nature Neuroscience, scientists have looked at the changes in gene expression associated with memories of positive associations and found that they are held in place by chemical modifications of the cells’ DNA.
via Ars Technica
Image: Oak Ridge National Lab