A systematic review of experiments examining the efficacy of repetitive transcranial magnetic stimulation in treating cocaine addiction revealed that the most effective results were achieved in studies utilizing high-frequency pulses (at least 5 Hz) targeting the left dorsolateral prefrontal cortex of the brain. Individuals undergoing this treatment reported significantly reduced cravings for cocaine and exhibited less impulsivity in response to extreme negative emotions. The findings were published in the journal Psychiatry Research.
Cocaine is a powerful stimulant drug derived from the leaves of the coca plant, native to South America. Although classified as an illicit drug practically everywhere, many use it recreationally for its euphoric and energizing effects. The use of this drug leads to increased alertness, feelings of extreme happiness, and a sense of increased energy. Cocaine can be snorted, smoked, or injected. However, its effects are short-lived, leading to a cycle of repeated use to maintain the desired high. This, in time, leads to cocaine addiction.
Cocaine addiction, or cocaine use disorder, is a chronic, relapsing condition marked by an uncontrollable desire to consume cocaine despite its detrimental effects. It arises from alterations in the brain’s reward system, resulting in intense cravings and compulsive drug-seeking behavior. The addiction can have severe physical, psychological, and social repercussions, including cardiovascular issues, mental health disorders, relationship problems, and financial and legal difficulties.
Traditional treatments for cocaine addiction involve a blend of behavioral therapies, support groups, and medications to alleviate withdrawal symptoms and cravings. However, these treatments often fall short of being fully effective, driving researchers to explore new treatment avenues.
One of the promising new methods to treat cocaine addiction is transcranial magnetic stimulation. Transcranial magnetic stimulation is a non-invasive technique that uses magnetic fields to stimulate nerve cells in the brain. It has become prominent as a way to treat depression, but multiple studies evaluated its potential for treating cocaine addiction as well.
Study author Andrea Amerio and her colleagues conducted a systematic review of these studies with the goal of evaluating their results i.e., making an assessment of how effective magnetic transcranial stimulation is in treating cocaine addiction based on their findings.
These authors conducted a search of the most popular electronic databases of scientific articles using various combinations of terms related to cocaine use, craving, dependence, and transcranial magnetic stimulation. They looked for articles published by the end of November 2022. The review focused on studies involving adults up to 65 years old diagnosed with cocaine use disorder, requiring at least two treatment groups and a comparison of rTMS efficacy against traditional treatments or a sham.
This search yielded 92 articles, but only 8 met the inclusion criteria after a manual review. All of these studies had two groups of participants. One group was undergoing transcranial magnetic stimulation, while the other was subjected to a sham treatment. A sham treatment typically means that participants were either made to believe that they were receiving transcranial magnetic stimulation when they were not or that participants in neither group knew whether the magnetic transcranial stimulation equipment used on them was actually turned on or not.
The studies varied in their stimulation targets within the prefrontal cortex of the brain, employing different frequencies of magnetic pulses. Some stimulated both sides of the prefrontal cortex, while others focused on the middle part (medial prefrontal cortex) or the upper part (dorsolateral). They used different frequencies of magnetic pulses.
The findings indicated that treatments utilizing at least 5 Hz, administered over multiple sessions and targeting the left dorsolateral prefrontal cortex, were most effective. These treatments, employing repetitive pulses at a regular frequency, were more effective than those using continuous theta burst stimulation patterns, which mimic the brain’s natural theta rhythm.
Participants in groups subjected to these treatments tended to show a significant decrease in craving for cocaine compared to groups treated with low-frequencies of pulses and those exposed to sham treatments. These treatments also seemed to produce a considerable amelioration in participants’ tendency to act rashly under extreme negative emotions compared to control groups.
“Although still scant and heterogeneous, the strongest evidence so far on the use of rTMS [repetitive transcranial magnetic stimulation] on individuals with CUD [cocaine use disorder] support the high-frequency stimulation over the left DLPFC [dorsolateral prefrontal cortex region of the brain] as a potential treatment of cocaine craving and impulsivity. Overall, rTMS has proven to be well tolerated and there were no significant differences in adverse events across the active and sham groups,” the study authors concluded.
The study systematizes the scientific knowledge on the effects of transcranial stimulation on cocaine addiction symptoms. However, it should be noted that the findings are based on the results of just a handful of studies, some of which reported no effects of the treatment.
The paper “Effects of transcranial magnetic stimulation on cocaine addiction: A systematic review of randomized controlled trials” was authored by A. Amerio, C. Baccino, G.S. Breda, D. Cortesi, V. Spiezio, L. Magnani, D. De Berardis, B. Conio, A. Costanza, G. De Paola, G. Rocca, G. Arduino, A. Aguglia, M. Amore, and G. Serafini.
