A stimulating environment may be the key to rehabilitation for drug and food addicts, according to a study by a Western Washington University professor.
Jeff Grimm, a behavioral neuroscience professor at Western, published a paper about the behavior of craving in rats in January, co-written by five Western undergraduates. The two-year study examined how environmental conditions, such as social interactions and engaging activities, affected rats conditioned to crave a sugar called sucrose.
The study found that environmental enrichment with more social interactions and activities for the rats reduced sucrose cravings both overnight and long-term.
Grimm is trying to understand the learning involved in food and drug addiction so he can study craving behavior when the addictive substance is taken away.
Sucrose-seeking in rats is a model for drug addiction in humans and provides insight to food addiction, Grimm said.
The kind of work done in behavioral psychology labs is related to a rehabilitation method called contingency management, which involves managing the environment of people with addictions, Grimm said.
“You can coax people to pay more attention to certain behaviors and tasks instead of taking drugs,” he said.
Grimm, who has worked at Western for since 2001, has a strong background in drug addiction and its process.
“I didn’t mean to study food addiction to start with,” he said. “I’ve been meeting people with extreme weight problems and thinking, this is interesting in its own right, and not just as a model for drug addiction.”
Research of food craving is still limited, said Jesse Barnes, co-author of the paper and Western alumnus.
“[Food craving research] may help to break down the thought that there is a big difference between drug addiction and food addiction,” Barnes said.
Kylan Dorsey is another co-author of the study and a Western alumnus.
“It’s not just a character flaw, it is a real disease,” Dorsey said. “People see drug addiction as a problem but food addiction is so overlooked.”
Adults in the U.S. weigh, on average, 24 pounds more than they did in 1960, according to the Center for Disease Control website. People who are overweight are at a higher risk for cardiovascular disease, diabetes and certain cancers.
As the obesity epidemic continues, more resources are going to be put into food addiction research, Dorsey said.
“It’s cool to be on the lead line and getting our research in now,” he said.
The study of environmental enrichment focuses on rehabilitation through social interactions and activities as opposed to pharmaceuticals or behavioral manipulation, Grimm said.
“Our rats live in a boring situation,” he said. “They don’t get a lot of interaction with other rats.”
Grimm’s lab introduced environmental enrichment by putting the rats in a bigger cage with other rats and toys.
Previous studies performed in Grimm’s lab examined the effect of environmental enrichment on long-term addiction, where he found the enrichment decreased sucrose craving in rats, Grimm said.
To form the addiction in the rats, Grimm conditioned them to press a lever that delivered a sucrose solution for them to drink, which was paired with a light and a tone. The light and tone are involved in “cue-reactivity,” which is a trigger that trained rats to associate it with sucrose. The sucrose solution was eventually withheld after an addiction had been established.
To test the craving level in the rats, the researchers observed how often the rats pressed the lever to administer the sucrose solution, and how they responded to seeing the light and hearing the tone.
When the rats were subjected to environmental enrichment away from the sucrose source, cue-reactivity decreased.
When presented with the opportunity to press the lever and receive sucrose, the rats were not as interested in pressing the lever, Grimm said.
“Sugar didn’t seem as important to them,” he said.
Cue-reactivity translates into human behavior as well, Dorsey said.
“A commercial for, say, a Wendy’s quadruple-pounder can trigger the same cue-reactivity as the light and tone,” he said. “It drives the motivation to get that food.”
Part of the recovery process of a drug or food addict is recognizing these triggers and redirecting their behavior, Grimm said.
In the study published in January, Grimm’s lab researched specific aspects of environmental enrichment and which methods were most effective, such as social interactions, the toys or having a bigger space. He also studied the effects of long-term exposure to environmental enrichment compared to short-term exposure.
The results of the study suggested that social interaction is not as necessary for rehabilitation as the toys.
Grimm and his student researchers are beginning to look into the brain chemistry of the rats, and how each treatment affects different parts of the brain. The new findings in the difference between long-term and short-term environmental enrichment will drive his studies, Grimm said.