According to new research, mice who received cocaine experienced rapid growth of new brain structures associated with learning and memory, suggesting a way in which drug use could lead to drug-seeking behavior.

Using a microscope, the researchers were able to peer directly into the brain’s nerve cells of living mice.  Within two hours of administering the drug, they observed a significant increase in the density of dendritic spines, which are responsible for signaling, in the frontal cortex. Conversely, mice given saline solution displayed no such increase.