Repeated use of cocaine and opioidsin addition to being addictive, alters the functioning of specific brain circuits useful for survival, given that they regulate fundamental behaviors, such as the search for food and water to satisfy hunger and thirst. A research of which Bowen Tan of the Laboratory of Molecular Genetics of the Rockefeller University in New York is the first signatory, published in the journal Sciencenow shows in great detail this alteration, which occurs above all at the level of an area of the brain called nucleus accumbens. A small structure that is part of the limbic system and which, among others, has a function of regulation of motivated behavior, perception of pleasure and gratificationcontrol of emotional reactions.
Basic needs for survival
The study was carried out on mice, to which these drugs were first repeatedly administered and then withdrawn, while the activity of specific groups of neurons in the nucleus accumbens was detected. Thus it was revealed a signal alteration in these circuits, which on a behavioral level resulted in a lack of the natural search for food and water. The results of the study show how some types of drugs can alter the neural circuits intended to ensure the satisfaction of basic needs for survival, however the acute and chronic action of drugs of abuse is certainly even more complex and their impact on decision-making processes it extends beyond this destruction of the organism’s homeostatic needs. In fact, in addiction to these drugs, a complete and problematic re-prioritization of the decision-making process occurs.
A strong economic-social impact
It is through these mechanisms that those who become addicted to cocaine or opiates take a short-sighted attitude towards their basic needs and ends up neglecting basic behaviors for maintaining a state of health and well-being, such as adequate and correct searching for food or liquids. The study was carried out using a sophisticated neuroscience technique, called «two-photon longitudinal calcium imaging», which allows us to study neuronal activity in real time within the brains of living animals and which uses fluorescence to visualize cellular structures within biological tissue. Drug addiction generates a significant portion of healthcare costs and has a significant economic-social impact. In particular, opioid addiction is responsible for approximately 80 percent of drug-related deaths.
