Some teens' marijuana use has been linked to disrupted communication between two key regions in the brain’s reward circuitry at age 20. Disrupted communication between the regions was associated with poorer psychosocial functioning at age 22.
Cocaine produces a portion of its rewarding effects by increasing levels of granulocyte-colony stimulating factor (G-CSF) in the brain’s reward center. Treatments that prevent G-CSF signaling in the nucleus accumbens might reduce motivation to use cocaine.
October 2017 High-frequency electrical stimulation of neurons deep in the brain can reduce rats’ relapse-like behavior and motivation to take heroin. The finding strengthens hope that deep brain stimulation might offer a new treatment alternative for opioid addiction, particularly for patients who have not benefited from other treatments.
This research traced the effects of cocaine-induced disruption of serotonin regulation in the ventral pallidum and orbitofrontal cortex. The findings suggest that these effects may contribute to drug-seeking and cocaine-associated cognitive impairments.
July 2014 The Scientific Director of NIDA’s Intramural Research Program talks about switching off animals’ compulsive cocaine seeking by optogenetically activating the prefrontal cortex, and the implications of this work for people. In an accompanying podcast, Dr. Bonci walks viewers through experiments that showed that prefrontal cortex activity levels may constitute a simple switch controlling whether or not animals compulsively seek cocaine.
Methamphetamine alters brain structures involved in decision-making and impairs the ability to suppress habitual behaviors that have become useless or counterproductive. The two effects were correlated, indicating that the structural change underlies the decline in mental flexibility.