Re-Regulation of Reward System After Opioid Dependence

In a recent study published in the Journal of Addiction Medicine, researchers from Penn State University College of Medicine found that patients in recovery from opioid dependence may show signs that the body’s natural reward systems are normalizing, even within a few months after drug withdrawal. The study provides evidence of a “physiological re-regulation” of disrupted brain and hormonal responses to pleasurable stimuli — both drug- and nondrug-related. The study included two groups of seven patients in treatment for opioid dependence. One group had recently gone through medically assisted opioid withdrawal (within the past one to two weeks), and the other group was in extended care, and had been drug-free for two to three months. The researchers performed several tests to assess changes in the brain’s reward system during early recovery. The test results showed several significant differences in the reward system between the two groups. In brain activity studies, patients with recent drug withdrawal showed heightened responses to drug-related cues, such as pictures of pills. In the extended-care patients, these increased responses to drug cues — in the prefrontal cortex, involved in attention and self-control — were significantly reduced. The study supports past research showing dysregulation of the reward system during early recovery from opioid dependence. It also provides evidence that these responses may become re-regulated during several weeks in residential treatment — a period of “clinically documented” abstinence from opioids. To read more about this study, click here.