Study Finds Intravenous Drug Administration Activates Brain’s ‘Salience Network’ and Offers Insights into Addiction Mechanisms
A new clinical trial conducted by the National Institute on Drug Abuse (NIDA) and the National Institute on Alcohol Abuse and Alcoholism (NIAAA) suggests that the brain’s “salience network” is only activated when drugs are administered intravenously and not orally. Rapid drug entry into the brain, such as through injection or smoking, effectively leads to heightened addiction potential in comparison to slower administration methods, such as oral intake. The study, published in Nature Communications, provides insights into the mechanics of addiction and potential avenues for new treatments.
Dr. Nora Volkow, NIDA Director and chief of the NIAAA Laboratory of Neuroimaging, expressed that this knowledge is crucial for informing prevention interventions and developing new therapies for substance use disorders, as well as addressing the current overdose crisis. The study utilized PET/fMRI imaging techniques to compare dopamine levels and brain activity in response to the administration of methylphenidate in twenty adults.
Results indicate that the brain’s salience network is associated with recognizing the subjective effects of drugs and was only activated with intravenous drug administration. The rapid release of dopamine with such administration corresponds to an increased potential for addiction, while slower increases with oral intake are linked with a lower risk of addiction. The researchers affirm that understanding the impact of drug administration routes on the brain’s response to drugs could pave the way for addressing substance use disorders more effectively.
