Image preferences expressed by cocaine-dependent individuals could help scientists develop new methods for determining the effectiveness of addiction treatment, according to new research from Brookhaven National Laboratories, eScience News reported Nov. 17.

Researcher Scott Moeller tested the image preferences of subjects who were addicted to cocaine and subjects in a control group who were not cocaine-dependent, and found that those who were addicted to cocaine showed a clear preference for the drug-related images.

Through a series of tests, both groups of subjects were asked to select cards with digital images that (unknown to the subjects) were classified as "cocaine-related," "pleasant," "unpleasant," or "neutral."

While individuals addicted to cocaine preferred cocaine-related images, those in the non-addicted group showed a clear aversion to these images and tended to select "pleasant" images, instead. However, those in the cocaine group rated "pleasant images" as more appealing than the cocaine-related images they seemed to prefer, suggesting that they may not be fully aware of their preferences and that such preferences may not be driven by pleasure or reward.

In earlier studies, scientists needed to administer cocaine or drugs that are pharmacologically similar to cocaine in order to test the drug's effects on the brain and behavior. "This behavioral study demonstrates for the first time that drug-related choice in cocaine addiction extends to abstract, non-pharmacological stimuli, facilitating the study of choice behavior in addiction without using actual cocaine," Moeller said.
 
"Tasks like the ones developed here could be used clinically to predict the effectiveness and outcomes of drug-addiction treatment, including abstinence or relapse," added Rita Goldstein, director of Brookhaven Laboratory Neuropsychoimaging group. "Simultaneous neuroimaging studies are needed to investigate the brain structures that underlie choices made by drug-addicted individuals."

Moeller presented the findings of the study at the Society for Neuroscience's recent annual meeting in Washington, D.C.