New studies show that two novel compounds powerfully suppressed animals’ pain responses, while producing little or none of the respiratory depression and liability for misuse and abuse associated with morphine and other typical opioids.
A brain imaging study strongly suggests that regular users of marijuana have smaller orbitofrontal cortex (OFC) volumes. Such a deficit could make it more difficult to change counterproductive behaviors, including drug use.
Individuals with weak signaling in a nicotine-sensitive brain circuit were more vulnerable to nicotine dependence than those with stronger signaling, according to a study conducted while the subjects’ brains were in a resting state. A second resting-state study finds that the same circuit appears to mediate dependence associated with a genetic risk factor for smoking.