A groundbreaking technique can help explore changes taking place within the deep regions of the brain at the cellular level, scientists have revealed.
The findings could lead to greater information on how the brain adapts to changing situations, including repeated drug exposure.
Researchers at Stanford University used time-lapse fluorescence microendoscopy, a technique that uses miniature probes to directly visualize specific cells over a period of time, to explore structural changes that occur in neurons as a result of tumor formation and increased stimulation in the mouse brain.
"Continued drug use leads to changes in neuronal circuits that are evident well after a person stops taking an addictive substance," said Nora D. Volkow, director of the National Institute on Drug Abuse (NIDA), US.
"This study demonstrates an innovative technique that allows for a glimpse of these cellular changes within the brain regions implicated in drug reward, providing an important tool in our understanding and treatment of addiction," she added.
The researchers focused on two brain regions for the study - the hippocampus and striatum.
The striatum, a brain region important for motor function and habit formation, is also a major target for abused drugs.
Some researchers believe that a shift in activity within the striatum is at least partly responsible for the progression from voluntary drug-taking to addiction.
The new technique could allow a better understanding of how these processes occur at the cellular level, leading to insights into mechanisms underlying addictive behaviours.
"The results should now allow neuroscientists to track longitudinally in the living brain the effects of drugs of abuse at the levels of neural circuitry, the individual neuron, and neuronal dendrites," said another researcher Mark Schnitzer.
The study has been published in Nature Medicine.