When asked to inhibit their response to a “cocaine-cues” video, active cocaine abusers were, on average, able to suppress activity in brain regions linked to drug craving, according to a new study at the U.S. Department of Energy’s Brookhaven National Laboratory. The results, to be published in an upcoming issue of NeuroImage, suggest that clinical interventions designed to strengthen these inhibitory responses could help cocaine abusers stop using drugs and avoid relapse.
“Exposure to drugs or stimuli associated with using drugs is one of the most common factors leading to relapse in drug-addicted individuals,” said Nora Volkow, Director of the National Institute on Drug Abuse and lead author on the paper.
“We know from previous studies that drug cues can trigger dramatic changes in the brain that are linked to a strong craving response,” added co-author Gene-Jack Wang, Chair of Brookhaven’s medical department. “This study provides the first evidence that cocaine abusers retain some ability to cognitively inhibit their craving responses to drug-related cues.”
Added Volkow, “Our findings provide enormous hope because they imply that cognitive interventions might be developed to maximize cocaine abusers’ success in blocking the drug-craving response to help them avoid relapse.”
The scientists used a brain-scanning technique called positron emission tomography (PET) and a radioactively “tagged” form of glucose — the brain’s main fuel — to measure brain activity in 24 active cocaine abusers during three different conditions: 1) while subjects simply lay in the scanner with eyes open; 2) while subjects watched a “cocaine-cues” video with scenes simulating the purchase, preparation, and smoking of crack cocaine; and 3) while subjects watched the video but were told to try to inhibit their craving response. Scans were performed in random order and on separate days.
In each scan, the PET camera tracked the radioactive signal from the tagged glucose as it was taken up by various regions of the brain. A stronger signal indicates higher metabolic activity in a particular brain region where more glucose is being used. This technique allows scientists to accurately monitor which brain regions are most active and how that activity changes with time or in response to different situations.
The scientists also monitored the research subjects’ heart rate and blood pressure and asked them to describe their level of craving during the scans. Compared with the baseline condition, the cocaine-cues video triggered increases in brain activity in several brain regions associated with drug craving, as well as increases in research subjects’ self-reports of craving.
When the research subjects were asked to inhibit their response to the video, and those scans were compared with the no-inhibition condition, metabolic activity decreased dramatically in brain regions involved in experiencing and anticipating rewards, and in a part of the brain that plays a role in assigning value, or salience, to different stimuli. During inhibition, research subjects also reported lower levels of craving compared with the no-inhibition video condition.
The researchers say the findings have significant clinical implications:
“Many current drug treatment programs help addicted individuals predict when and where they might be exposed to drug cues so that they can avoid such situations,” Volkow said. “While this is a very useful strategy, in real-word situations, cues may come up in unexpected ways. Our findings suggest that a clinical strategy that trains cocaine abusers to exert greater cognitive control could help them selectively inhibit the craving response whenever and wherever drug cues are encountered — whether expectedly or unexpectedly.”
Because inhibitory control is crucial for regulating emotions and desires, the findings from this study could have implications for other disorders involving loss of behavioral control, such as gambling and obesity.
This study was supported by the intramural program from the National Institutes of Health Intramural Research Program at the National Institute on Alcohol Abuse and Alcoholism. Brookhaven Lab’s infrastructure for PET imaging and radiotracer development also receive support from the DOE Office of Science.
Karen McNulty Walsh | EurekAlert!
Physics of bubbles could explain language patterns
25.07.2017 | University of Portsmouth
Obstructing the ‘inner eye’
07.07.2017 | Friedrich-Schiller-Universität Jena
Physicists working with researcher Oriol Romero-Isart devised a new simple scheme to theoretically generate arbitrarily short and focused electromagnetic fields. This new tool could be used for precise sensing and in microscopy.
Microwaves, heat radiation, light and X-radiation are examples for electromagnetic waves. Many applications require to focus the electromagnetic fields to...
Strong light-matter coupling in these semiconducting tubes may hold the key to electrically pumped lasers
Light-matter quasi-particles can be generated electrically in semiconducting carbon nanotubes. Material scientists and physicists from Heidelberg University...
Fraunhofer IPA has developed a proximity sensor made from silicone and carbon nanotubes (CNT) which detects objects and determines their position. The materials and printing process used mean that the sensor is extremely flexible, economical and can be used for large surfaces. Industry and research partners can use and further develop this innovation straight away.
At first glance, the proximity sensor appears to be nothing special: a thin, elastic layer of silicone onto which black square surfaces are printed, but these...
3-D shape acquisition using water displacement as the shape sensor for the reconstruction of complex objects
A global team of computer scientists and engineers have developed an innovative technique that more completely reconstructs challenging 3D objects. An ancient...
Physicists have developed a new technique that uses electrical voltages to control the electron spin on a chip. The newly-developed method provides protection from spin decay, meaning that the contained information can be maintained and transmitted over comparatively large distances, as has been demonstrated by a team from the University of Basel’s Department of Physics and the Swiss Nanoscience Institute. The results have been published in Physical Review X.
For several years, researchers have been trying to use the spin of an electron to store and transmit information. The spin of each electron is always coupled...
26.07.2017 | Event News
21.07.2017 | Event News
19.07.2017 | Event News
27.07.2017 | Materials Sciences
27.07.2017 | Life Sciences
27.07.2017 | Power and Electrical Engineering