Many researches have analysed psychological, physical, and even social effects of narcotics consumption. Nevertheless, drug addiction had never before been related to the decision-making capacity of the individual . The “Behavioural medicine and health psychology” research group of the Universidad de Granada, coordinated by Professor Miguel Pérez García and Professor Antonio Verdejo García, of the Department of Personality, Assessment and Psychological treatment, have carried out two studies which show that drug users make decisions without taking into account the context involved (with non-adaptation) or future consequences (they look only for immediate benefits).
For the first of these conclusions, the UGR researchers analysed a sample population of 97 narcotic multi-addicted consumers (addicted to alcohol, cocaine, heroine or a combination of the latter two substances) who had followed the therapeutic programme called “Proyecto Hombre” and had attended the Regional Centre for Rehabilitation known as “Cortijo Buenos Aires”. The researchers also analysed a control group of 81 non-drug users with a similar profile. “Our work consisted of presenting a simple stimulus (a geometric shape) to the individuals who, after examining it thoroughly, were asked to choose one of two shapes as being different from the other”, explains Antonio Verdejo. The results of the study showed that drug addicts choose a shape without taking into account the reference previously presented to them, while non-drug users took the decision according to the context presented.
Not all the information
It is very easy to explain this fact: “Drug addicts are intellectually normal,” states Miguel Pérez, “but their orbitofrontal cortex, which is the part of the brain on which decision-making depends, have been damaged”. Their particular viewpoint when making a decision causes them “to act according to their interests and objectives, without considering all the information that they should, such as rules that have been established”.
Researchers from the UGR have also revealed that drug addicts present what Antonio Damasio, the last to be awarded the Scientific Research Prince of Asturias award, called “future myopia”. This means that they do not consider the final consequences of their acts, but only the immediate results. Regardless of the type of act, it is aimed only at obtaining an immediate reward, even if this entails terrible future consequences”, explains Antonio Verdejo. In this case, his study was performed with 106 drug addicts, with a minimal abstinence period of two weeks.
The research was conducted with the “discounting of delayed rewards”, a technique by which the longer the delay, the greater the reward the individual receives. To put this into practice, Professor Verdejo and Professor Pérez García used a card game in which the individual starts with a fixed amount of cards, the amount increasing or decreasing according to the decisions made.
Using different tests, Spanish researchers found that 76.4% of drug-addicted patients had “future myopia” when making decisions, while 23.6% take into account the future consequences of their acts.
Reference:
Antonio Verdejo García and Miguel Pérez García. Department of Personality, Assessment and Psychological treatment of the Universidad de Granada.
Phone: +34 958 242 948 / +34 958 244 251. E-mail: averdejo@ugr.es, mperezg@ugr.es
