Primate Insights: How Nonhuman Primate Studies Illuminate Substance Use Disorders

Nonhuman primates—monkeys for the most part—are paving the way headfirst into exciting new research. They have always played a fundamental role in research that explores neuroscience concepts and sheds light on brain functions, cognitive processes, and neurological diseases. They are critical to finding new approaches to the treatment of neurological disorders, especially substance use disorders (SUDs).

SUDs have been a long-standing issue that affects millions of people worldwide. In 2023, 48.5 million people, age 12 and older, were diagnosed with SUDs, with a staggering 28.9 million of those people with an alcohol use disorder (U.S. Department of Health and Human Services). Luckily, nonhuman primates are leading the charge for SUD care by providing essential data that change how researchers perceive the disorders and treatment options for addiction.

Dr. Aqilah McCane, an assistant professor at the Oregon National Primate Research Center, is doing research on SUDs and has a special interest in alcohol use disorder. She and Dr. Kathleen A. Grant, a professor at the center, are studying how excess alcohol consumption by adolescent nonhuman primates interferes with the way certain brain regions function and affects the ability to learn. The goal is to identify specific nonhuman primates predisposed to addiction based on their learning patterns, map out brain regions conveying substance resilience or vulnerability, and be able to predict who will struggle with SUDs.

With this unique approach, researchers can apply their findings to the general population by measuring adolescents’ learning abilities and providing targeted prevention of addiction early in life. “Researchers, based on current studies, hope to predict who will be in which drinking classification [such as drinking in moderation, binge drinking, heavy drinking, etc.] based on behavior,” McCane explained. “The goal is to understand who’s at risk and devise preventive measures.”

Ultimately, researchers at the Oregon National Primate Research Center are focused on whether they can prevent illness, and possibly how to treat it if it has already set in.

Combining these two behavioral paradigms—learning patterns and brain activities—can create a new outlook on preventive measures for addiction. Providers will be able to measure vulnerability before addiction even becomes a problem and warn people of possible susceptibility early in life when there is still room for change. This advanced method is a new road for health care, with research focused on finding individualized care methods that can stop addiction or prevent it altogether.

So, how exactly are nonhuman primates treated during the research process? Animal research provides pivotal insights into current human issues, with humane and ethical treatment being researchers’ top priority.

“As scientists, we are bound by ethics to take what we do very seriously,” said McCane. “It’s important to us to convey that we work with animals to improve human conditions. It is necessary.” Animal-care personnel, alongside researchers, take a unique approach to ensuring every animal receives expert care. For example, if Tommy, the primate, prefers bananas while John prefers grapes, care workers would take note and try to meet as many of the animals’ preferences as possible. Animal-care employees are highly receptive to each nonhuman primate, maintaining individualized and humane treatment that ensures all the animals are happy and healthy.

Overall, nonhuman primates are pivotal to advancements in science and are the key to unlocking a better future for mental health care, according to McCane. SUDs are a prevalent issue in our world and scientists like McCane are just starting to uncover the pathways to ideal treatments with the help of nonhuman primates.