Patients with schizophrenia take less risky decisions and have less tolerance for economic injustices

A study conducted by Spanish and French universities analyses the economic behaviour of people with schizophrenia or antisocial personality disorder who also consume cocaine.Meet â•fi Meet

Researchers from the Jaume I University (UJI), the CEU Cardenal Herrera University (CEU UCH) of Castellón and French University Bourgogne Franche-Comité (UBFC) of Dijon, have just published a study that evaluates the risk-based decisions and the perception of injustice in the economic realm of people who consume cocaine and who have associated mental pathologies: schizophrenia or antisocial personality disorder. The results, which have been published today in high-impact scientific journal Scientific Reports, from editorial group Nature, reveals that people with schizophrenia take less risky decisions and have less tolerance for economic-type injustices in comparison to healthy people. The study has been funded by the Ministry of Science, Innovation and Universities and by the Foundation of the Provincial Hospital of Castellón.

In the study, participants took part in an experiment with two types of decisions. Firstly, they had to choose between different lottery bets, in a task aimed at evaluating their degree of aversion to economic risk. Secondly, they took part in a modified version of the “dictator game” which makes it possible to arouse altruistic or non-altruistic attitudes, when faced with situations of both advantageous and disadvantageous economic injustices. People with mental diseases face these types of decision-making processes influenced by past experiences linked to risk and comparing and finding differences with other experiences. This is why both scenarios were designed with the goal of observing their decision-making process in both circumstances.

The results of the study of the UJI, CEU UCH and UBFC show that participants with antisocial personality disorder associated to the consumption of cocaine did not show significant differences compared to the control group, integrated by students from different university levels of the UJI who voluntarily participated in the experiment. However, among the people who consume cocaine with schizophrenia there were statistically significant differences: on one hand, their economic decisions were less risky when choosing lottery bets and, on the other, they showed less tolerance for the economic injustice in the modified dictator game.

Economic decisions and psychosocial treatment

In light of these results, and given the lack of clear patterns in prior studies, the authors of the research highlight the interest in studying the economic decision-making process in order to design psychosociological treatments for dual pathology: mental pathologies associated with drug consumption. Gonzalo Haro, Medicine professor at the CEU UCH, says that experimental economy studies such as this one “can contribute to a suitable evaluation of the patients on behalf of psychiatrists regarding a possible legal incapacitation to make use of their money and assets, especially in the case of people addicted to cocaine who suffer schizophrenia.”

As Abel Baquero, fellow professor of the CEU UCH, says, “the results of the research are further proof of the importance of studies on economic behaviour as a useful tool, both in mental health and addictions, as they make it possible to have valuable additional information for the treatment of dual pathology.” Schizophrenia and antisocial personality disorder are the two pathologies that are most associated to the consumption of cocaine, the most consumed illegal substance in Europe. It is believed that 2.3 million European youths aged 15 to 34 consume it. In Spain, cocaine is the cause of 36.5% of cases that require treatment for drug consumption, and half of the total cases tended to in Emergency Rooms linked to drug consumption.

The team of behavioural experimentalists of the UJI, coordinated by professor Aurora García Gallego, has ample experience in the implementation of experimental methodology on very diverse population samples, although this has been the first field experiment with patients. “The type of results obtained and the external validity showed on behalf of the scientific community has left an open door that is as important as it is encouraging for future studies of relevance for medicine,” he says.

Research team

The researchers that have conducted this study have been Gerardo Sabater Grande, Aurra García Gallego and Noemí Herranz Zarzoso, from the Laboratory of Experimental Economy (LEE) and the Department of Economy of the UJI; Gonzalo Haro and Abel Baquero, from the TXP research group of the CEU UCH of Castellón; and Nikolaos Georgantzis, from the Burgundy School of Business of the UBFC (Dijon, France), and also a member of the LEE team and the Department of Economy of the UJI. CEU UCH professor Gonzalo Haro leads the Dual Pathology Unit of the Provincial Hospital of Castellón, where the people addicted to cocaine who took part in the experimental tests of the study undergo treatment.

More information on the study: “Risk-taking and fairness among cocaine-dependent patients in dual diagnoses: Schizophrenia and Anti-Social Personality Disorder”, in Scientific Reports. DOI: 10.1038/s41598-020-66954-2

www.nature.com/articles/s41598-020-66954-2