Zapping away cocaine addiction with laser light
By Ben Coxworth
April 5, 2013
Like so many other illicit drugs, cocaine can be extremely, destructively addictive. Recent research suggests, however, that ridding people of such addictions may be as simple as zapping them on them scalp. In a study conducted at the National Institutes of Health (NIH), and at the Ernest Gallo Clinic and Research Center at UC San Francisco, scientists were able to turn cocaine addiction on and off in rats via pulses of laser light to their brains.
The scientists started with light-sensitive proteins known as rhodopsins, which they inserted into the neurons of the rats’ prefrontal cortex via genetic engineering. The prefrontal cortex is associated with impulse control – something that addicts tend to lack.
Those neurons were then able to be activated by exposing them to laser light, which was fed into the animals’ brains through implanted fiber optic cables. The result was that compulsive drug-seeking behavior could be instantly turned off in cocaine-addicted rats, by turning on the neurons.
Conversely, deactivating the neurons (by turning off the light) caused non-addicted rats to exhibit addicted behavior. This makes sense, as research has shown that both addicted rats and addicted humans tend to have a low amount of prefrontal cortex activity.
While the scientists aren’t necessarily suggesting that lasers be hooked up to cocaine addicts’ heads, they do believe that the same sort of effect could be achieved through the existing technique of transcranial magnetic stimulation (TMS), in which an electromagnetic field is applied to the brain through the scalp.
Human trials are scheduled to begin soon at NIH, in which cocaine-addicted subjects will receive TMS treatments to their prefrontal cortex. A paper on the research was published this week in the journal Nature.