The study, by Rinah Yamamoto and colleagues at McLean Hospital in Belmont, Massachusetts assessed the suspected link by contrasting reactions to varying perceived availability of the drug. The researchers suggest that more appropriate care could be given if the degree of dependency and abuse were assessed in a natural environment with a potential access to the drug, rather than in a clinical setting.
Yamamoto explains that craving, is an intense and often irrepressible urge to seek and consume the drug, which can result in relapses even after extended periods of abstinence. In searching for effective therapies, understanding how craving, cognition and motivation are entwined is essential.
The researchers administered intravenous cocaine (0.2 mg/kg) to individuals with cocaine dependence who were not seeking treatment. "Unblinded" participants knew for certain they would receive cocaine, while the "blinded" group knew there was a 33 percent chance of getting the drug. The researchers obtained subjective ratings of craving, high, rush and low from the volunteers along with their heart rate and blood pressure measurements. Measurements were collected prior to cocaine administration and every minute for 20 minutes thereafter.
The results showed that several hours prior to the infusion all volunteers had similar craving scores. However, those volunteers who knew they were to receive a cocaine infusion said they felt a greater craving immediately prior to the receipt of cocaine than the "blinded" volunteers who did not know whether the infusion was placebo or the genuine drug. The team also found that the unblinded subjects experienced a more rapid onset of high and rush cocaine responses along with significantly higher cocaine-induced heart rate elevations.
The findings suggest that the cocaine expectancy state modulates the user's subjective and objective responses to the drug. These data are consistent with the previous studies demonstrating that drug-induced elevated dopamine concentrations in the brain may prime drug users to associate the cues around the source of dopamine boost (e.g., cocaine) with the pleasure experienced once the drug is taken.
Charlotte Webber | alfa
Innovative genetic tests for children with developmental disorders and epilepsy
11.07.2018 | Christian-Albrechts-Universität zu Kiel
Oxygen loss in the coastal Baltic Sea is “unprecedentedly severe”
05.07.2018 | European Geosciences Union
For the first time ever, scientists have determined the cosmic origin of highest-energy neutrinos. A research group led by IceCube scientist Elisa Resconi, spokesperson of the Collaborative Research Center SFB1258 at the Technical University of Munich (TUM), provides an important piece of evidence that the particles detected by the IceCube neutrino telescope at the South Pole originate from a galaxy four billion light-years away from Earth.
To rule out other origins with certainty, the team led by neutrino physicist Elisa Resconi from the Technical University of Munich and multi-wavelength...
For the first time a team of researchers have discovered two different phases of magnetic skyrmions in a single material. Physicists of the Technical Universities of Munich and Dresden and the University of Cologne can now better study and understand the properties of these magnetic structures, which are important for both basic research and applications.
Whirlpools are an everyday experience in a bath tub: When the water is drained a circular vortex is formed. Typically, such whirls are rather stable. Similar...
Physicists working with Roland Wester at the University of Innsbruck have investigated if and how chemical reactions can be influenced by targeted vibrational excitation of the reactants. They were able to demonstrate that excitation with a laser beam does not affect the efficiency of a chemical exchange reaction and that the excited molecular group acts only as a spectator in the reaction.
A frequently used reaction in organic chemistry is nucleophilic substitution. It plays, for example, an important role in in the synthesis of new chemical...
Optical spectroscopy allows investigating the energy structure and dynamic properties of complex quantum systems. Researchers from the University of Würzburg present two new approaches of coherent two-dimensional spectroscopy.
"Put an excitation into the system and observe how it evolves." According to physicist Professor Tobias Brixner, this is the credo of optical spectroscopy....
Ultra-short, high-intensity X-ray flashes open the door to the foundations of chemical reactions. Free-electron lasers generate these kinds of pulses, but there is a catch: the pulses vary in duration and energy. An international research team has now presented a solution: Using a ring of 16 detectors and a circularly polarized laser beam, they can determine both factors with attosecond accuracy.
Free-electron lasers (FELs) generate extremely short and intense X-ray flashes. Researchers can use these flashes to resolve structures with diameters on the...
13.07.2018 | Event News
12.07.2018 | Event News
03.07.2018 | Event News
20.07.2018 | Health and Medicine
19.07.2018 | Earth Sciences
19.07.2018 | Power and Electrical Engineering