Erasing Addiction with the Help of Neuroscience

Addiction plagues our country, so it is no surprise that it is a hot topic in neuroscience research at the moment.  Dr. Stephan Steidl studies the reward pathway that leads to addiction.  He uses optogenetics in mice to take a deeper look at how the mesolimbic and mesocortical pathways contribute to reward.  Using this technique, he is able to stimulate certain regions of the brain by implanting a light in a mouse’s brain and switching the light on and off.  One of Dr. Steidl’s studies specifically looked at dopamine which causes “excitation of LDTg (Laterodorsal Tegmental Nucleus) inputs to the Ventral Tegmental Area (VTA).”  He found that stimulating those neurons as a reward to a behavior greatly reinforced the behavior in mice, so much so that they would do it up to 300 times in 30 minutes.  Dr. Steidl’s research identifies a specific area of the brain that contributes to supporting addictive behaviors.  

 A recent National Geographic article entitled “How Science is Unlocking the Secrets of Addiction,” looks into even more research on addiction.  It mentions a study by Bonci and colleagues that also used optogenetics in mice.  However, this study focused on the area in the prefrontal cortex that when stimulated weakens addictions.  That finding complements Steidl’s research, and together they point toward practical applications in humans.  Dr. Gallimberti, a psychiatrist and toxicologist, saw the opportunity for human application and did just that through the use of Transcranial Magnetic Stimulation (TMS).  TMS is a large magnet that when held next to areas of the brain will briefly interrupt the neural circuitry by stimulating or inhibiting specific regions.  By stimulating the inhibitory area in the prefrontal cortex, the hope was that addictions would stop.  In the studies performed on cocaine addicts, TMS treatment was found to be more effective than traditional care for addictions.  Thus, TMS is a practical next step for humans to benefit from optogenetics research like Dr. Steidl’s. 

Dr. Steidl’s Research:

Steidl, Stephan, et al. "Operant Responding for Optogenetic Excitation of Ldtg Inputs to the  

VTA Requires D1 and D2 Dopamine Receptor Activation in the Nacc." Behavioural Brain Research, vol. 333, 30 Aug. 2017, pp. 161-170. EBSCOhost, doi:10.1016/j.bbr.2017.06.045.

National Geographic Article:

Smith, Fran. “How Science Is Unlocking the Secrets of Addiction.” National Geographic, 22

Aug. 2017, www.nationalgeographic.com/magazine/2017/09/the-addicted-brain/.

Photo:
From the National Geographic article. Taken by Max Aguilera-Hellweg.