1. Introduction
Neuroenhancement in healthy subjects is the improvement of cognitive, emotional and motivational functions through the consumption of various categories of substances [
1]. Cognitive enhancers may be readily available substances, such as caffeine and energy drinks, or psychostimulants, when used to improve cognitive functions [
2]. Caffeinated products, food supplements, and energy drinks are considered “soft enhancers”, whereas prescription drugs (beta-blockers, modafinil, and methylphenidate) and drugs of abuse (alcohol, cannabis, cocaine, and amphetamines) are defined as “neuroenhancers” [
3]. University students are at high risk of neuroenhancement [
4]. Some studies suggested that neuroenhancers were helpful for improving concentration, making it possible to study for longer [
5], to increase working memory performance, to boost self-esteem, and to cope with stressors (academic overload, competition with peers, constant pressure to succeed, financial burden) [
5,
6]. This risky behavior appears to increase the likelihood of using the stimulant again, at higher doses and/or in combination with drugs.
There are numerous concerns regarding neuroenhancement in Europe [
4,
7,
8,
9,
10,
11]. A study of Swiss university students found that 13.8% had tried to enhance their cognitive performance at least once with prescription drugs (7.6%) or drugs of abuse (7.8%) [
4]. In France, data relative to neuroenhancement among university students are scarce. In the English literature, only two studies were published. The first one, conducted in 2014, reported that among a non-representative sample of 206 medicine and pharmacology students questioned, 67.4% declared to have consumed at least one cognitive enhancer in the past year: The majority consumed vitamin C (84.8%) and caffeine tablets (71.9%), and only 5.8% used prescription drugs [
12]. The second study was conducted in 2016. Lifetime prevalence of cognitive enhancer use among undergraduate and postgraduate medical students was 33%. The commonly used substances were caffeine tablets and energy drinks (29.7%), followed by prescription drugs (6.7%) and illicit drugs (5.2%) [
10]. These studies investigated prevalence of neuroenhancement only among health students, while neglecting participants with other curriculums who are also susceptible to consume neuroenhancers. Furthermore, the investigated substances do not represent all categories of substances consumed for cognitive enhancement [
10,
12].
When comparing the different countries, the highest lifetime prevalence rates of alcohol and drug use were found among Eastern European countries [
13,
14]. This high prevalence of drugs and alcohol use in the general young population could influence their use exclusively for the purposes of cognitive enhancement in Romanian universities. To date, no studies have been performed to either confirm or refute this hypothesis.
There is no study investigating the prevalence of all categories of cognitive enhancers among French and Romanian students with different study curriculums. We conducted a cross-sectional study to determine the use, motivations, and factors associated with the use of soft enhancers, drugs of abuse, and prescription drugs among French and Romanian university students.
4. Discussion
This survey is the first to provide information about the use of a large range of products (prescription drugs, drugs of abuse, and soft enhancers), reasons for neuroenhancement, and the factors associated with neuroenhancement for university students at French and Romanian universities. The use in the previous year only for the neuroenhancement was 55.0% for soft enhancer consumption, 4.3% for use for drugs of abuse, and 2.2% for prescription drugs. These findings are consistent with the findings of previous European studies on this subject [
3,
21]). In our study, Romanian students had the highest rates of soft enhancer use (84.9%), and the trends observed were similar to those reported among students at Puerto Rico (88%), American (92%), and Omanian (97%) universities [
22,
23,
24]. The most widely used substance in our cohort was coffee (45.3%), followed by vitamins (26.9%) and energy drinks (10%). Caffeinated beverages, such as coffee, tea, and energy drinks, are generally considered socially acceptable and form the basis of the coping strategies used by students to enhance cognitive function and to manage stressful academic situations [
23,
24,
25]. However, the misuse of soft enhancers can have a number of adverse effects, including breathing problems, an abnormal heartbeat, increases in blood pressure, diuresis and natriuresis, a decrease in insulin sensitivity, high levels of irritability, and chronic daily headaches if the usual dose is not taken [
24,
25,
26]. It might be important (for future studies) to ask about the dosing of these substances to learn more about patterns of use and any indications of risk.
We found a prevalence of drugs of abuse consumption for the neuroenhancement of 4.3% (8% among Romanians students and 3% among French students). The most frequently used were alcohol (4.0%) and cannabis (3.2%) followed by amphetamines (0.8%) and cocaine (0.4%). Lifetime prevalence among Swiss university students was reported of 7.8% (5.6% for alcohol and 2.5% for cannabis) [
4]. Euphoric effects that occur after using drugs of abuse can be explained by the changes in the dopamine and serotonin levels in the brain, which might increase motivation [
27], whereas frequent use has addictive potential and can generate anxiety, aggression, and paranoia [
26]. Alcohol and cannabis use is related to increases in skipping class and lower grades due to interference with academic performance and assignments [
28].
In our study, the prevalence of prescription drug use was 2.2%, almost beta-blockers (1.8%), and low use of methylphenidate (0.5%) and modafinil (0.1%). Drug consumption rates were higher for Romanian students than for French students. Studies among German students reported a similar prevalence, ranging between 0.26% and 2.0% [
10]. Unlike the majority of European studies, which reported the preference of methylphenidates and modafinil by students, in our study, beta-blockers were the most used. Methylphenidate is prescribed to treat Attention-Deficit Hyperactivity Disorder (ADHD), modafinil is used to treat narcolepsy [
29] and beta blockers, prescribed for cardiac arrhythmia, also have an anxiolytic effect [
30]. Because of their extensive misuse by students, European governments have imposed strong restrictions on the prescription and delivery of methylphenidates and modafinil [
31,
32,
33,
34,
35,
36]. For example, dextroamphetamine and mixed amphetamine salts are prescribed to treat ADHD in the United States, whereas they are banned in Switzerland or Germany [
34,
35]. In France, these stimulants are subjected to a double prescription system. They are initially prescribed by psychiatrists and then the prescription should be confirmed by a general practitioner [
30,
32]. These modalities could limit methylphenidate and modafinil use but could lead to the research of other alternatives. Figures for the US are more worrying due to the misuse of stimulants prescribed for ADHD [
36,
37,
38]. A meta-analysis of 21 US studies examining the prevalence of prescription drug misuse revealed that the past-year prevalence rates were 5% to 9% in high schools and 5% to 35% in colleges [
36]. Methodologically, whereas the larger survey studies typically result in smaller rates of stimulant misuse, smaller, single-site studies with often face-to-face interviews, report higher risk. College practitioners and psychologists could assess for a learning disorder or attention deficit disorder to offer evidence-based medicine treatment. This would potentially reduce binge alcohol drinking and illicit substance use [
39].
Smoking and binge drinking in recreational contexts were factors associated with drugs of abuse and soft enhancers for neuroenhancement. Our multivariate model strengthens the recent description in the US student population [
40]. No significant association with eating disorders was detected for any of the three categories of substance. The association with methamphetamine has been recently demonstrated but despite a difference in our study, it was not significant, perhaps due to a lack of power [
41].
Healthcare students are more frequent users of soft enhancers than other students. Healthcare students often experience emotional difficulties dealing with the challenges of their training [
10], which can lead to burnout in some cases. Limiting the amount of knowledge and the psychological pressure because of competition during the first year may improve the use of psychostimulants in this population. Limiting sleep deprivation because of shifts may lessen psychostimulant use in healthcare students [
35].
The primary reasons for using neuroenhancers reported by the university students were to stay awake (69.3%), to improve concentration (55.5%), to reduce stress (40.9%), and to improve memory (39.6%). The promotion of wakefulness was also reported by university students as one of the main reasons for neuroenhancement [
36].
These findings indicate that challenges in the management of academic stress and workloads are behind most use of prescription and illicit drugs for neuroenhancement [
4,
22,
31,
42]. Students see cognitive enhancement as a way of coping with stressors and, therefore, increasing academic performance [
37,
43].
In our sample, 74.4% of users reported that neuroenhancement met their expectations and 40.5% reported an improvement in academic performance. However, it could be subjective effects. Several studies have called into question the cognitive performance benefits of drugs of abuse or prescription drugs in students [
1,
44,
45]. A meta-analysis showed that expectations regarding the effectiveness of these drugs exceed their real effects [
1]. This hypothesis was supported by a placebo-controlled study demonstrating that Modafinil affected the perceived change in physical performance and tiredness, but not cognitive performance in healthy adults [
46]. Another double-blind placebo-controlled study reported that there were no significant differences in word recall tasks between sleep-deprived participants who received methylphenidate and those who received a placebo. However, significant differences were found between subjects who assumed they had received methylphenidate and those who assumed they had received a placebo [
1]. Munro et al. cannot rule out the possibility that neuroenhancement prevented declines in academic performance, but conclude that students who engaged in neuroenhancement showed no increases in their academic performance and gained no detectable advantages over their peers [
45]. Prescription drug consumption could affect neuroplasticity and may, therefore, result in deterioration of cognitive performance and even the personality of users [
47].
In our study, many side effects were recorded, such as sleep disorders, palpitations, weariness, anxiety, loss of appetite, and aggressiveness. Another type of risk regarding the safety of cognitive neuroenhancers is addiction. A nationwide survey estimates that almost one in twenty misusers of prescription drugs meet the criteria for dependence or abuse [
47]. Physiological changes in the brain caused by repeated use could lead to increased use of these drugs in more demanding academic environments [
48]. Psychological addiction could also be generated because, with neuroenhancers, activities seem more interesting and rewarding [
43], which might give the feeling that it is impossible to succeed without the drug use [
49]. Furthermore, there is a real risk of delivering counterfeit medications [
50] and a desire to use some smart drugs, but they did not use them, mainly due to the fear of side effects [
51]. The medical safety and efficacy of prescription drugs varies with the substance used and side effects are not only pharmacological but also psychological and physiological. Repantis et al. [
1] concluded that in the majority of trials, the drugs were well tolerated and, to some degree, improved memory, but there was no consistent evidence with repeated doses. A proper consumption would involve making enhancements available while managing their risks [
52]. Ethical debates about neuroenhancement are between the issue of whether individuals have the right to use neuroenhancers and its potential social outcomes [
52].
Our findings in this report have several limitations. The study did not include information from all the students at each of the three universities. It was a convenience sample, which could lead to a selection bias with an under- or overestimation of the neuroenhancement use. This bias could be limited by the anonymity of the questionnaire. Our French sample includes a bit more females than the origin population: Two-thirds of students are females in France, and almost three-quarters in Cluj-Napoca university. This convenience sample does not allow generalizing the results to other French and Romanian universities. However, we recruited a heterogeneous sample with respect to all major academic disciplines in the two French universities. The present study also has important strengths: The combination of similar studies at three different institutions in two countries, the use of specific questions regarding the broad range of neuroenhancement substances.
This study is one of the most detailed and consistent surveys shedding light on neuroenhancement among university students in Western and Eastern Europe. Specific questions concerning differences in neuroenhancement prevalence according to institution, substance category, and purpose of use were considered. Our results raise the alarm concerning potentially risky behavior among university students, particularly those in Romania. More measures are required to avoid neuroenhancement with drugs of abuse or prescription drugs and, thus, to limit other risky behaviors. Educational programs are also required to increase student awareness of the problems caused by neuroenhancement, and to change attitudes and beliefs to decrease the risk.
