A new study finds the frequency of dreams involving drinking and drug use decreases the longer a person is in recovery.

Investigators from the Massachusetts General Hospital Recovery Research Institute studied people in recovery from alcohol and drug use disorders. They note that vivid dreams involving drinking and drug use are common among people in recovery, Science Daily reports. The study included more than 2,000 people who were in recovery from a significant alcohol or drug use disorder. About one-third reported having relapse dreams after entering recovery. The frequency of the dreams lessened the longer a person was in recovery, the researchers report in the Journal of Substance Abuse Treatment.

Relapse dreams are more common in people with more severe clinical histories of alcohol and other drug use disorders, the study found.

“The association between the decreasing frequency of these dreams and the length of time in recovery suggests that, as the body and mind gradually adapt to abstinence and a new lifestyle, psychological angst about relapse diminishes,” said lead author John F. Kelly, Ph.D.