Substances used and prevalence rates of pharmacological cognitive enhancement among healthy subjects

Stimulant abuse as a coping strategy-Forensic and criminal consequences of stimulant abuse for neuroenhancement

Pharmacological neuroenhancement (PN) describes the use of divergent psychoactive substances to enhance mental performance (cognition) without medical need. This kind of substance abuse takes place predominantly in stressful situations. Users implicitly-or even explicitly-describe this kind of drug abuse to be a coping strategy. Regarding the decision making process whether to use PN drugs or not, users indicate that legal aspects to be decisive. However, the legal situation has been neglected so far. To elucidate the German legal situation, PN substances have to be divided into over-the-counter drugs, prescription drugs and illegal drugs. Amphetamines have the highest cognition-enhancing potential, followed by modafinil and caffeine-containing substances. It is pointed out that the use of both freely available and prescription PN substances and narcotics without medical indication have so far been largely exempt from punishment under German law. However, individuals (physicians, bus and truck drivers, etc.) taking PN substances may expose others at risk due to wrong decisions (driving or treatment), errors based on side effects of the used substances. Therefore, the protection of life and health of others could legitimize criminal regulation.

Identifying Determinants of Neuro-Enchancement Substance Use in Students

Abstract. Background: Use of Neuro-Enhancement Substances (NES) such as prescription drugs, illicit drugs, or alcohol to improve cognition, prosocial behavior, and performance is increasing among students. Aims: The study applied a multi-theory, integrated theoretical model to identify motivational and social cognition determinants of NES use among students. Methods: A prospective longitudinal design was adopted with 306 high school (66.8% female; Mage = 17.31 years, SD = 0.93) and 692 university (70.5% female; Mage = 24.97 years, SD = 6.64) students. They completed measures of motivation, social cognition constructs, and planning with respect to studying behavior and NES use. Results: Well-fitting structural equation models indicated the pervasive influence of autonomous motivation, attitudes, subjective norms, and perceived behavioral control for studying, as well as of attitudes, subjective norms, and perceived behavioral control for NES use. Inclusion of past NES use increased explained variance in NES use and attenuated model effects, but the pattern of effects remained. Multi-group analyses indicated consistency in the pattern model effects across high school and university students. Limitations: The study findings might not be generalizable, as student samples were not randomly recruited. Furthermore, NES use only relied on self-report, and its assessment did not consider different NES substances. Finally, there was no assessment of implicit attitudes and habits toward studying and NES use. Conclusions: Findings extend prior literature by demonstrating the integrated guiding view that students’ motivation and beliefs about studying influence their beliefs about and use of NES. Furthermore, the findings provide starting points for interventions targeting the reduction in NES use.

Intelligenzsteigerung durch Neuroenhancement?

Zusammenfassung. Die menschliche Intelligenz gehört zu den bestuntersuchten psychologischen Merkmalen, in denen interindividuelle Differenzen bestehen. Die mehr als 100jährige Forschungsgeschichte hat einen hoch belastbaren Wissensstand hervorgebracht; dieser umfasst die Definition, die Psychometrie, die (ontogenetische) Entwicklung, die Struktur, die Vorhersagekraft für real-life-Variablen, das Wissen über elementar-kognitive, verhaltensgenetische und neurobiologische Grundlagen der Intelligenz, u.v.m. Jüngst steht zudem die Frage des ‚enhancements‘ der Intelligenz im Fokus, eine Frage, die nicht zuletzt durch die aktuelle philosophische Strömung des Transhumanismus stark an Bedeutung gewinnt. Der Transhumanismus nimmt eine substanzielle Erhöhung (enhancement) von Fähigkeiten und anderen (auch) psychologischen Eigenschaften des Menschen ins Zentrum und postuliert, dass ein soziokultureller Fortschritt – und letztlich das Überlegen des Homo Sapiens und unseres Planeten – erst durch technologischen Fortschritt ermöglicht werde. Viele Transhumanisten stellen eine substanzielle Steigerung der Intelligenz in den Vordergrund, die primär durch (neuro–)‌technologische und pharmakologische Maßnahmen zu bewerkstelligen seien. Diese Debatten sind jedoch oft gekennzeichnet durch übertrieben optimistische Annahmen der Möglichkeiten moderner neurowissenschaftlicher Methoden bei gleichzeitiger Vernachlässigung der potenziellen negativen Folgen für das Individuum, für die Gesellschaften und insgesamt für unsere Spezies. Im gegenständlichen Überblicksbeitrag werden behaviorale, neuroelektrische und pharmakologische Methoden im Hinblick auf ihr aktuelles Potenzial einer Steigerung der individuellen Intelligenz analysiert. Die zwischenzeitlich zu diesen Fragen vorliegenden experimentellen Studien, sowie verfügbare Metaanalysen lassen allerdings den Schluss zu, dass bislang keine der gegenwärtig verfügbaren Methoden das Potenzial haben, die individuelle Intelligenz substanziell zu steigern. Und selbst falls solche möglicherweise in absehbarer Zeit zur Verfügung stünden, müssen zuvor sowohl individuelle als auch gesellschaftliche (negative) Konsequenzen einer kritischen Analyse unterzogen werden. Diese sind Gegenstand einer abschließenden Diskussion.

Exploring the use of cognitive enhancement substances among Portuguese university students

Background

Prescription drug use and the consumption of substances to enhance college students' cognitive performance, described as pharmacological cognitive enhancement (PCE), is a known phenomenon potentially impacting individuals' health. University and college students are two specific subpopulations noted to use PCE (up to 17%, on average). To our knowledge, no data have been published on the use of PCE drugs among university students at a national level in Portugal and the factors that might be associated with this usage.

Objective

The main objective was to estimate the prevalence of PCE use by Portuguese university students and to identify the PCE substances commonly used by university students, i.e., those classified as prescription drugs and other legal and nonprescribed substances, including food supplements.

Methods

The study followed a cross-sectional exploratory, descriptive design and pursued a convenience sample of students from Portuguese public and private universities (22 higher education institutions).

Results

From a sample of 745 university students, 32% indicated the use of prescribed and nonprescribed substances. The most consumed substances were food supplements with CNS stimulants being the most frequent prescription-only drugs but not necessarily accessed through a medical prescription. A significant statistical association was found between substance consumption and the field of study. Health science students reported more food supplements and drug intake, allegedly under prescribed regimens, compared to humanities and exact sciences students. The study discusses the need to better understand the competitive societies that produce and support young students' outputs and the perceived ‘need’ for performance-enhancing substances.

Conclusions

One-third of the university students aimed to improve their performance by pharmacological cognitive enhancement, with a preference for food supplements dispensed in pharmacies. PCE substance consumption in higher education is thus non-negligible. The study suggests the need to improve regulations on potential inequalities in academic rankings and success and an observant attitude concerning implications that negatively affect health in the long run.

The Impact of Instant Coffee and Decaffeinated Coffee on the Gut Microbiota and Depression-Like Behaviors of Sleep-Deprived Rats

Objective

Based on our previous research, chronic paradoxical sleep deprivation (PSD) can cause depression-like behaviors and microbial changes in gut microbiota. Coffee, as the world’s most popular drink for the lack of sleep, is beneficial to health and attention and can eliminate the cognitive sequelae caused by poor sleep. The purpose of this study is to investigate the effects of coffee and decaffeinated coffee on PSD rats.

Research Design and Methods

A total of 32 rats were divided into four groups: control group, PSD model group, conventional coffee group, and decaffeinated coffee group. Behavioral tests, including sucrose preference test, open field test, forced swimming test, and tail suspension test, as well as biochemical detection for inflammatory and antioxidant indexes were performed. The effects of coffee and decaffeinated coffee on the gut microbiota of PSD rats were investigated by 16S rRNA gene sequencing.

Results

Coffee and decaffeinated coffee significantly improved the depression-like behaviors. Moreover, the serum levels of interleukin-6 and tumor necrosis factor alpha were decreased in both coffee and decaffeinated coffee groups, as well as the levels of superoxide dismutase and GSH-Px were increased. Gut microbiota analysis revealed that the abundance of S24-7, Lachnospiraceae, Oscillospira, and Parabacteroides were significantly increased in PSD rats, while the abundance of Akkermansia and Klebsiella were significantly decreased. After the treatment of coffee and decaffeinated coffee, the abundance of the above gut microbiota was all restored in different degrees. Coffee had relatively more significant effects on PSD-induced depressive-like behaviors, while the difference between coffee and decaffeinated coffee was not obvious in correcting the disorder of gut microbiota.

Conclusions

These findings have shown that both coffee and decaffeinated coffee are effective for sleep deprivation-induced depression-like behaviors and the dysbiosis of gut microbiota and indicated that caffeine may be not the only key substance of coffee for regulating gut microbiota.

Drinking coffee enhances neurocognitive function by reorganizing brain functional connectivity

The purpose of this study was to identify the mechanisms underlying effects of coffee on cognition in the context of brain networks. Here we investigated functional connectivity before and after drinking coffee using graph-theoretic analysis of electroencephalography (EEG). Twenty-one healthy adults voluntarily participated in this study. The resting-state EEG data and results of neuropsychological tests were consecutively acquired before and 30 min after coffee consumption. Graph analyses were performed and compared before and after coffee consumption. Correlation analyses were conducted to assess the relationship between changes in graph measures and those in cognitive function tests. Functional connectivity (FC) was reorganized toward more efficient network properties after coffee consumption. Performance in Digit Span tests and Trail Making Test Part B improved after coffee consumption, and the improved performance in executive function was correlated with changes in graph measures, reflecting a shift toward efficient network properties. The beneficial effects of coffee on cognitive function might be attributed to the reorganization of FC toward more efficient network properties. Based on our findings, the patterns of network reorganization could be used as quantitative markers to elucidate the mechanisms underlying the beneficial effects of coffee on cognition, especially executive function.

Just "Like Coffee" or Neuroenhancement by Stimulants?

Introduction: Pharmacological neuroenhancement (PN) is a topic of increasing importance and prevalence among students. However, there is a lack of differentiating PN substances, according to their psychoactive effects. In particular, there is a lack of data about PN by caffeinated drinks, even if coffee is a common and broadly used Neuroenhancer because of its cognitively enhancing effects regarding wakefulness, alertness and concentration.

Materials and Methods: A web-survey was developed for German students and alumni about the non-medical use of caffeine for PN contained questions about coffee, caffeinated drinks and energy drinks, caffeine pills and methylxanthine tea regarding frequency and further contextual factors.

Results: Six hundred and eighty-three participants completed the survey. Nearly all participants knew about PN (97.7%). 88.1% admitted using some over-the-counter substances. For PN purposes, coffee was used by 72.9% followed by energy drinks (68.2%) and cola drinks (62.4%). Methylxanthine containing tea was used for PN purposes, too (black tea 52.3%, green tea 51.7%). 1.8% admitted using illegal substances or prescription drugs, too.

Discussion: Using legal methylxanthine containing drinks for PN seems to be extremely common with coffee and energy drinks being the preferred substances, while illegal and prescription drugs are only minimally used. Further studies should investigate the awareness of methylxanthine containing drinks as well as its character to be a flavoring drink or a neuroenhancer.

Social Justice Theories as the Basis for Public Policy on Psychopharmacological Cognitive Enhancement

Psychopharmacological cognitive enhancements could lead to a higher quality of life of healthy individuals with lower cognitive capacities, but the current regulatory framework does not seem to enable access to this group. This article discusses why Sen’s Capability Approach could open up such access, while two other modern social justice theories – utilitarianism and Rawls’ Justice as Fairness – could not. In short, the utilitarian approach is proven to be inadequate, due to practical reasons and having a low chance of real-world success. Rawls’ Justice as Fairness seems to be problematic because of conflicting stances that follow from his First Principle of Justice. The Capability Approach has the greatest chance of success in the context of these substances, because of arguments that can be identified under the banners of agency/self-respect and the way the public views those who take the capability path out of their poor situation. The article also discusses general and practical problems with psychopharmacological cognitive enhancement that should be addressed when writing new policy on this topic.

Feigning ADHD and stimulant misuse among Dutch university students

The increasing number of university students seeking diagnosis of attention-deficit/hyperactivity disorder (ADHD), and findings of an increased stimulant misuse among university students, has raised concerns regarding the credibility of the symptoms of those students. However, most of our current knowledge refers to university students in North America and less is known about this issue on European campuses. The present survey aimed to collect opinions on feigning ADHD and to estimate the prevalence of stimulant misuse among 1071 university students in the Netherlands. The majority of students expressed liberal attitudes towards feigning ADHD. Also, a substantial number of respondents considered feigning ADHD themselves or know someone who feigns ADHD. Furthermore, 68% of students assumed benefits of taking stimulants without prescription and 16% have indeed already taken stimulants without prescription. Feigning ADHD and misuse of prescription medication are prevalent issues among Dutch students. The results underline the need for a careful diagnostic evaluation of individuals for ADHD. Furthermore, efforts are required in order to prevent stimulant drug trafficking and misuse among university students.

Psychiatric Comorbidity and Stress in Medical Students Using Neuroenhancers

Background: Pharmacological neuroenhancement (PN) is a common healthcare problem at least among students. PN seems to be associated with stressful situations. There is a lack of data about personal characteristics, comorbidities, and coping strategies regarding stress and factors of resilience in students and medical staff. Methods: A web-based survey about the non-medical use of PN drugs with a focus on neuroenhancement was developed and distributed among medical students throughout Germany; the questionnaire was open in April and May of 2020. The survey contained questions about the use of well-known PN drugs, frequency, special purposes, reasons for the use, psychiatric disorders, use of psychotropic drugs apart from PN purposes, and factors of resilience using the brief resilience scale. Results: Data of 1,159 students of medicine were analyzed. The most frequently used substances for PN were coffee (78.8% lifetime prevalence rate), energy drinks (45.7%), caffeine tablets (24.3%), methylphenidate (5.2%), illicit amphetamines (2.0%), and cocaine (1.7%). 98.4% suspected that PN drug use could lead to addiction. PN drug use specifically for PN was significantly associated with the use of (a) any psychotropic drug (other than neuroenhancers), (b) any psychiatric disorder, and (c) higher values of feeling pressure to perform in professional/students' life and in private life as well as (d) the subjective feeling of pressure to perform to be burdening and (e) harmful to one's own health. PN drug use in general was significantly associated with being less resilient. The use of illicit PN drugs, over the counter drugs and prescription drugs was associated with being less resilient. Conclusion: This study indicates that PN with legal and illegal drugs is a widespread phenomenon among German medical students. Users seem to be more often burdened by psychiatric disorders, especially addictive disorders, the perception of stress, pressure to perform and low levels of resilience. These aspects should be considered in further investigation of PN drug use.

Cognitive enhancement effects of stimulants: a randomized controlled trial testing methylphenidate, modafinil, and caffeine

RATIONAL

At all times humans have made attempts to improve their cognitive abilities by different means, among others, with the use of stimulants. Widely available stimulants such as caffeine, but also prescription substances such as methylphenidate and modafinil, are being used by healthy individuals to enhance cognitive performance.

OBJECTIVES

There is a lack of knowledge on the effects of prescription stimulants when taken by healthy individuals (as compared with patients) and especially on the effects of different substances across different cognitive domains.

METHODS

We conducted a pilot study with three arms in which male participants received placebo and one of three stimulants (caffeine, methylphenidate, modafinil) and assessed cognitive performance with a test battery that captures various cognitive domains.

RESULTS

Our study showed some moderate effects of the three stimulants tested. Methylphenidate had positive effects on self-reported fatigue as well as on declarative memory 24 hours after learning; caffeine had a positive effect on sustained attention; there was no significant effect of modafinil in any of the instruments of our test battery. All stimulants were well tolerated, and no trade-off negative effects on other cognitive domains were found.

CONCLUSIONS

The few observed significant positive effects of the tested stimulants were domain-specific and of rather low magnitude. The results can inform the use of stimulants for cognitive enhancement purposes as well as direct further research to investigate the effects of stimulants on specific cognitive domains that seem most promising, possibly by using tasks that are more demanding.

Medical Students' Attitudes Towards Pharmacological Cognitive Enhancement With Methylphenidate

OBJECTIVE

The aim of this study was to assess medical students' perception of pharmacological cognitive enhancement (PCE) with methylphenidate and to determine whether this perception differs between junior and senior medical students.

METHODS

The second and fifth year medical student groups of 2017 at a specific university completed self-administered questionnaires in order to investigate if there were a difference in their attitudes towards methylphenidate use for PCE.

RESULTS

A total of 353 students were included as follows: 135 second year and 218 fifth year students. Fifth year students were more aware of PCE with methylphenidate than second year students (94% versus 87%; p value = 0.02). Many students (second year = 86%; fifth year = 71%; p value = 0.2469) were of the opinion that methylphenidate could enhance academic performance. Sixty-six percent of all the students were concerned about the fairness of PCE; 93% were concerned about the harmfulness of methylphenidate. There were no statistical significant differences in the attitudes towards methylphenidate use for PCE between the two groups of junior and senior students.

CONCLUSION

In both groups, the majority of students were against the use of methylphenidate for PCE in students without attention deficit and hyperactivity disorder. Their attitudes regarding the use of methylphenidate for non-medical purposes did not differ significantly. Addressing the topic of PCE with medical students is essential, and the impact on their practice can be an important direction for future research.

The Dark Triad of personality and attitudes toward cognitive enhancement

Background

Cognitive enhancement (CE) refers to the voluntary improvement of human cognitive capabilities. Few studies have examined the general attitude of the public towards CE. Such studies have suggested that the use of CE is considered largely unacceptable by the public. In parallel, past research indicates that individuals scoring high on the Dark Triad of personality (Machiavellianism, narcissism, and psychopathy) and competitiveness have atypical views of ethical questions. In this study, we examined (a) whether attitudes towards CE are associated with individual differences in the Dark Triad of personality as well as in trait and contextual competitiveness and (b) whether the Dark Triad moderates the effect of trait and contextual competitiveness on attitudes towards CE.

Method

US employees (N = 326) were recruited using Mechanical Turk. Participants completed a web survey. Data were analyzed by means of (robust) hierarchical regression and (robust) ANCOVAs.

Results

The Dark Triad of personality and one of its subscales, Machiavellianism, predicted positive attitudes towards CE. Neither trait competitiveness nor contextual competitiveness were linked to general attitudes towards CE, but the DT was a positive moderator of the association between contextual competitiveness and positive attitudes.

Conclusion

Our findings extend the incipient knowledge about the factors relating to favourable views of CE by highlighting the role of dark personality traits in shaping such views. Our study further shows contextual factors can play a differentiated role with respect to such attitudes depending upon dark personality traits. Implications for policy-making are discussed.

Personalizing neuromodulation

In the era of "big data", we are gaining rich person-specific information about neuroanatomy, neural function, and cognitive functions. However, the optimal ways to create precise approaches to optimize individuals' mental functions in health and disease are unclear. Multimodal analysis and modeling approaches can guide neuromodulation by combining anatomical networks, functional signal analysis, and cognitive neuroscience paradigms in single subjects. Our progress could be improved by progressing from statistical fits to mechanistic models. Using transcranial magnetic stimulation as an example, we discuss how integrating methods with a focus on mechanisms could improve our predictions TMS effects within individuals, refine our models of health and disease, and improve our treatments.

[Informations on psychotropics and their adaptations for patients suffering from mental disorders in France during the SARS-CoV-2 epidemic]

The 2019-20 coronavirus pandemic (SARS-CoV-2; severe acute respiratory syndrome coronavirus 2) has dramatic consequences on populations in terms of morbidity and mortality and in social terms, the general confinement of almost half of the world's population being a situation unprecedented in history, which is difficult today to measure the impact at the individual and collective levels. More specifically, it affects people with various risk factors, which are more frequent in patients suffering from psychiatric disorders. Psychiatrists need to know: (i) how to identify, the risks associated with the prescription of psychotropic drugs and which can prove to be counterproductive in their association with COVID-19 (coronavirus disease 2019), (ii) how to assess in terms of benefit/risk ratio, the implication of any hasty and brutal modification on psychotropic drugs that can induce confusion for a differential diagnosis with the evolution of COVID-19. We carried out a review of the literature aimed at assessing the specific benefit/risk ratio of psychotropic treatments in patients suffering from COVID-19. Clinically, symptoms suggestive of COVID-19 (fever, cough, dyspnea, digestive signs) can be caused by various psychotropic drugs and require vigilance to avoid false negatives and false positives. In infected patients, psychotropic drugs should be used with caution, especially in the elderly, considering the pulmonary risk. Lithium and Clozapine, which are the reference drugs in bipolar disorder and resistant schizophrenia, warrant specific attention. For these two treatments the possibility of a reduction in the dosage - in case of minimal infectious signs and in a situation, which does not allow rapid control - should ideally be considered taking into account the clinical response (even biological; plasma concentrations) observed in the face of previous dose reductions. Tobacco is well identified for its effects as an inducer of CYP1A2 enzyme. In a COVID+ patient, the consequences of an abrupt cessation of smoking, particularly related with the appearance of respiratory symptoms (cough, dyspnea), must therefore be anticipated for patients receiving psychotropics metabolized by CYP1A2. Plasma concentrations of these drugs are expected to decrease and can be related to an increase risk of relapse. The symptomatic treatments used in COVID-19 have frequent interactions with the most used psychotropics. If there is no curative treatment for infection to SARS-CoV-2, the interactions of the various molecules currently tested with several classes of psychotropic drugs (antidepressants, antipsychotics) are important to consider because of the risk of changes in cardiac conduction. Specific knowledge on COVID-19 remains poor today, but we must recommend rigor in this context in the use of psychotropic drugs, to avoid adding, in patients suffering from psychiatric disorders, potentially vulnerable in the epidemic context, an iatrogenic risk or loss of efficiency.

Use of new psychoactive substances to mimic prescription drugs: The trend in France

Among the expanding world of New Psychoactive Substances (NPS), Designer Medicines (DM) are designed to mimic psychoactive drugs and might lead to adverse events of various severity. The DM category includes designer benzodiazepines (DB), phenmetrazine, modafinil, methylphenidate analogs, and novel synthetic opioids (NSO). To investigate DM-related complications in France, all data on NPS collected in the French Addictovigilance network database through spontaneous reports (SRs) and the annual survey on deaths related to the abuse of licit and illicit psychoactive substances (DRAMES survey) between 2009 and 2017 were analyzed. From 2009-2017, about 800 cases of NPS-related abuse or somatic complications were reported to the French Addictovigilance Network, including 71 fatal cases (9%). DM use progressively increased over the years, particularly after 2013 (4% of all SRs on NPS in 2011 versus 14 % in 2017). Moreover, DM were implicated in 17 % of NPS-related deaths in France, just after cathinones (43 %) and dissociative drugs (22 %). NSO, DB and phenidate analogs were identified in 42 %, 25 % and 25 % of all DM-related death reports, respectively. DM seem to interest a new target group of users that includes mainly patients and healthy people rather than substance users. The availability on the Internet of compounds mimicking therapeutic drugs is a worrying phenomenon that could lead to their uncontrolled use.

Pharmacokinetic and pharmacodynamic of the cognitive enhancer modafinil: Relevant clinical and forensic aspects

Modafinil is a nonamphetamine nootropic drug with an increasingly therapeutic interest due to its different sites of action and behavioral effects in comparison to cocaine or amphetamine. A review of modafinil (and of its prodrug adrafinil and its R-enantiomer armodafinil) chemical, pharmacokinetic, pharmacodynamic, toxicological, clinical and forensic aspects was performed, aiming to better understand possible health problems associated to its unconscious and unruled use. Modafinil is a racemate metabolized mainly in the liver into its inactive acid and sulfone metabolites, which undergo primarily renal excretion. Although not fully clarified, major effects seem to be associated to inhibition of dopamine reuptake and modulation of several other neurochemical pathways, namely noradrenergic, serotoninergic, orexinergic, histaminergic, glutamatergic and GABAergic. Due its wake-promoting effects, modafinil is used for the treatment of daily sleepiness associated to narcolepsy, obstructive sleep apnea and shift work sleep disorder. Its psychotropic and cognitive effects are also attractive in several other pathologies and conditions that affect sleep structure, induce fatigue and lethargy, and impair cognitive abilities. Additionally, in health subjects, including students, modafinil is being used off-label to overcome sleepiness, increase concentration and improve cognitive potential. The most common adverse effects associated to modafinil intake are headache, insomnia, anxiety, diarrhea, dry mouth and raise in blood pressure and heart rate. Infrequently, severe dermatologic effects in children, including maculopapular and morbilliform rash, erythema multiforme and Stevens-Johnson Syndrome have been reported. Intoxication and dependence associated to modafinil are uncommon. Further research on effects and health implications of modafinil and its analogs is steel needed to create evidence-based policies.

Cognitive Enhancing Drugs in Sport: Current and Future Concerns

Sporting authorities and policy makers have warned of a radical increase in the availability and use of so-called 'smart' drugs, which putatively deliver cognitive enhancements in the form of improved focus, concentration, alertness, and rapid decision-making. Although the potential for health risks is well documented when it comes to performance enhancing drugs in sport, the health implications of cognitive enhancing drugs (CEDs) remain unclear. Objectives: This article aims to provide a foundational understanding about CEDs and their application in sport. It considers what little is known about the types, nature, impact, and implications of their use for athletes and sport policy. Method: A narrative literature review was undertaken to ascertain the emerging role of CEDs beyond their clinical use to treat prescribed disorders, including the limited studies in the sporting domain. This review also considered literature pertinent to the impact of CEDs in sport and the challenges for sport policy. Results: Given the prospects of negative health impacts, policy-makers interested in preventing and controlling the use of CEDs, as well as reducing harm to athletes at all levels of performance, need guidance. This article highlights multi-faceted concerns and shines a spotlight on key issues for sporting bodies to consider regarding the critical impact that widespread use and adoption of these substances might entail. Conclusion: While the World Anti-Doping Agency (WADA) is seemingly awake to the threat posed, actions to circumvent the spread of CEDs throughout sport are nascent and require greater understanding and attention.

Pharmakologisches Neuroenhancement in Deutschland

Hintergrund Die Angaben zur Verbreitung des pharmakologischen Neuroenhancements (pNE) in Deutschland variieren stark. Der Beitrag diskutiert, inwieweit dieser Umstand methodischen Aspekten der Prävalenzstudien geschuldet sein könnte.

Methode Der Beitrag gibt einen Überblick zum aktuellen Forschungsstand und beleuchtet methodische Probleme der Prävalenzforschung in Deutschland.

Ergebnisse Die Prävalenzangaben variieren je nach Erhebungsmethode, abgefragtem Zeitpunkt der Einnahme und untersuchten Zielgruppen und Stoffen bei verschreibungspflichtigen und illegalen Substanzen zwischen einem und 39%. Für frei erhältliche Mittel werden z. T. höhere Prävalenzen berichtet. Es lassen sich 4 große methodische Probleme der Forschung identifizieren: 1.) Die Heterogenität der Definitionen, 2.) die Heterogenität der Befragungsmethoden und die Qualität der Stichproben(ziehungen), 3.) Defizite bei der Frageformulierung, 4.) das Fehlen wichtiger Angaben in den zugehörigen Veröffentlichungen.

Schlussfolgerung Verlässliche Aussagen zur Verbreitung von pNE in Deutschland sind schwierig. Zwischen den Untersuchungen bestehen inhaltlich und methodisch große Unterschiede, die Ergebnisse lassen sich nur bedingt vergleichen. Notwendig sind regelmäßige bevölkerungsrepräsentative Erhebungen auf Basis einheitlicher Definitionen.

Nootropic drugs: Methylphenidate, modafinil and piracetam - Population use trends, occurrence in the environment, ecotoxicity and removal methods - A review

Pharmaceuticals which originally were designed to treat people with neurological and psychiatric conditions, e.g. Alzheimer's disease or attention deficit hyperactivity disorder (ADHD), are nowadays often misused by students as a 'brain doping' substances. These substances are known as nootropic drugs, smart drugs or cognitive enhancers, as they increase memory, attention and concentration of healthy individuals. Since they are easily available illicitly, their consumption is observed to be growing. Currently, these pharmaceuticals started gaining researchers' attention, especially since they have been recently detected in wastewater, surface water and even drinking water. This review summarises the current state of knowledge on nootropic drugs in terms of their population use trends and ethics, occurrence in the environment and detection techniques, toxicity and removal methods, in example of methylphenidate, modafinil and piracetam - three most popular nootropics. It points out that the main sources of knowledge on cognitive enhancers illicit use are often inconsistent questionnaires, which are not supported by wastewater analysis to become more veracious. Simultaneously, the studies concerning toxicity and removal methods of nootropic drugs are still limited and in many cases environmentally irrelevant. Although the prescription rules has been subjected to more strict control in developed countries, regulatory frameworks with regard to their ecosystem occurrence are still lacking and should be introduced. Moreover, the use of environmentally relevant concentrations in toxicity studies should be a standard, leading to proper ecotoxicity risk assessment. Based on this review, it is recommended to routinely monitor nootropics and their metabolites in waste- and surface waters.

Moral decision making under modafinil: a randomized placebo-controlled double-blind crossover fMRI study

RATIONALE

Modafinil is increasingly used by healthy humans as a neuroenhancer in order to improve cognitive functioning. Research on the effects of modafinil on cognition yielded most consistent findings for complex tasks relying on the prefrontal cortex (PFC).

OBJECTIVES

The present randomized placebo-controlled double-blind crossover study aimed to investigate the effect of a single dose of modafinil (200 mg) on everyday moral decision making and its neural correlates, which have been linked to the ventro- and dorsomedial PFC.

METHODS

Healthy male study participants were presented with short stories describing everyday moral or neutral dilemmas. Each moral dilemma required a decision between a personal desire and a moral standard, while the neutral dilemmas required decisions between two personal desires. The participants underwent this task twice, once under the influence of modafinil and once under placebo. Brain activity associated with the processing of the dilemmas was assessed by means of functional magnetic resonance imaging.

RESULTS

For the processing of moral vs. neutral dilemmas, activations were found in a network of brain regions linked to social cognitive processes including, among others, the bilateral medial PFC, the insula, and the precuneus. Modafinil was found to increase the number of moral decisions and had no effect on brain activity associated with dilemma processing. Exploratory analyses revealed reduced response-locked activity in the dorsomedial PFC for moral compared to neutral dilemmas under modafinil, but not under placebo.

CONCLUSIONS

The results are discussed in terms of altered predictions of others' emotional states under modafinil, possibly due to higher processing efficiency.

How perceived substance characteristics affect ethical judgement towards cognitive enhancement

Some individuals seek to enhance their cognitive capabilities through the use of pharmacology. Such behavior entails potential health risks and raises ethical concerns. The aim of this study was to examine whether a precursor of behavior, ethical judgement towards the use of existing biological cognitive enhancers (e.g., coffee, legal and illegal drugs), is shaped by the perceived characteristics of these cognitive enhancers. Students and employees completed an online questionnaire which measured perceived characteristics of 15 substances presented as potential cognitive enhancers and a measure of ethical judgement towards these cognitive enhancers. Results of mixed model regression analyzes show that ethical judgement is more favourable when cognitive enhancers are perceived as being legal, familiar, efficient, and safe for users’ health, supporting all hypotheses. Results further show that 36% of variance (in the null model) lies at the level of cognitive enhancers and 21% at the level of participants. In conclusion, cognitive enhancers vary widely in terms of ethical judgement, which is explained by the perception of the mentioned characteristics. Implications regarding prevention and policy-making are discussed.

Inhibition of Methamphetamine Self-Administration and Reinstatement by Central Blockade of Angiotensin II Receptor in Rats

The molecular mechanism and treatment of methamphetamine (METH) use disorder remain unclear. The current study aimed to investigate the role of central angiotensin II receptor (ATR) in drug taking and seeking behavior associated with METH use disorder. The effect of an ATR type 1 (AT1R) antagonist, candesartan cilexetil, on the reinforcing and motivational effects of METH was first assessed using the animal model of METH self-administration (SA) and reinstatement. The levels of dopamine D2 receptor (D2R) and AT1R were subsequently examined. Furthermore, the present study determined the expression of microRNAs (miRNAs) by comparing METH SA, METH-yoked, and Saline-yoked groups. The target miRNAs were further overexpressed in the nucleus accumbens (NAc) via a lentivirus vector to investigate the effects of target miRNAs on METH SA maintained under a fixed ratio 1, progressive ratio, and cue/drug reinstatement of METH SA. The potential role of the AT1R-PLCβ-CREB signaling pathway was finally investigated. The results suggest that AT1R blockade effectively reduced METH SA and reinstatement, in conjunction with the counter-regulation of D2R and AT1R. A total of 17 miRNAs targeting Ang II in NAc were found to be associated with the voluntary intake of METH. Furthermore, overexpression of specific miR-219a-5p targeting AT1R-regulated METH SA and reinstatement. The AT1R-PLCβ-CREB signaling pathway was found to be associated with the effect of AT1R on the drug-taking and drug-seeking behavior involving METH use disorder.

Coffee time: Low caffeine dose promotes attention and focus in zebrafish

In this study we investigated the ability of zebrafish to discriminate visual signs and associate them with a reward in an associative-learning protocol including distractors. Moreover, we studied the effects of caffeine on animal performance in the task. After being trained to associate a specific image pattern with a reward (food) in the presence of other, distractor images, the fish were challenged to locate the exact cue associated with the reward. The distractors were same-colored pattern images similar to the target. Both the target and distractors were continually moved around the tank. Fish were exposed to three caffeine concentrations for 14 days: 0 mg/L (control, n = 12), 10 mg/L (n = 14), and 50 mg/L (n = 14). Zebrafish spent most of the time close to the target (where the reward was offered) under the effects of 0 and 10 mg/L caffeine, and the shortest latency to reach the target was observed for the 10-mg/L caffeine group. Both caffeine treatments (10 and 50 mg/L) increased the average speed and distance traveled when compared to the control group. This study confirms previous results showing that zebrafish demonstrate conditioned learning ability; however, low-dose caffeine exposure seems to favor visual cue discrimination and to increase zebrafish performance in a multicue discrimination task, in which primarily focus and attention are required in order to obtain the reward.

Moral Attitudes Toward Pharmacological Cognitive Enhancement (PCE): Differences and Similarities Among Germans With and Without PCE Experience

Pharmacological cognitive enhancement (PCE), the use of illicit and/or prescription drugs to increase cognitive performance, has spurred controversial discussion in bioethics. In a semi-structured interview study with 60 German university students and employees, differences and similarities in moral attitudes toward PCE among 30 experienced participants (EPs) vs. 30 inexperienced participants (IPs) were investigated. Substances EPs used most often are methylphenidate, amphetamines, tetrahydrocannabinol and modafinil. Both EPs and IPs addressed topics such as autonomous decision making or issues related to fairness such as equality in test evaluation and distortion of competition. While most EPs and IPs were convinced that the decision of whether or not to use PCE is part of their individual freedom, their views varied considerably with regard to fairness. IPs considered issues related to fairness as much more critical than EPs. Thus, a person’s moral attitudes toward PCE may not only depend on moral common sense, but also on whether they have used illegal and/or prescription drugs for PCE before. This points to the importance of including the various relevant stakeholder perspectives in debates on the ethical and social implications of PCE.

Building Conceptions of Cognitive Enhancement: University Students' Views on the Effects of Pharmacological Cognitive Enhancers

BACKGROUND

Use of prescription stimulants for cognitive enhancement in healthy individuals has been of growing interest to the academic community. University students can be prone to use these pharmacological cognitive enhancers (PCEs) for their perceived academic benefits.

OBJECTIVES

We aimed to understand university students' beliefs about the factors influencing PCE use, the cognitive and health effects of the drugs, and how these conceptions are interrelated.

METHODS

Data were collected through focus groups with 45 students at the University of Toronto in 2015/2016. We used thematic analysis to extract key themes and cooccurrence coefficients to evaluate the overlap between these themes.

RESULTS

We found that participants perceived users as either struggling students or high-achieving ones. Alleged benefits of PCEs included enhanced focus, attention, memorization, and grades, but did not include increased intelligence or long-term cognitive enhancement. Participants disagreed on whether ADHD diagnosis would affect how PCEs worked and how "needing the drug" was determined. Mentions of nonspecific side effects were common, as was the possibility of misuse (e.g., addiction, abuse). Though not an initial aim of the study, we uncovered patterns pertaining to whom participants used as sources of information about different themes. We propose that social learning theory provides a useful framework to explain how the experiences of peers may shape the conceptions of our participants. Conclusions/Importance: Our findings highlight that conceptions surrounding PCEs are multileveled, and informed by a variety of sources, including peers. This should be considered in the development of interventions geared toward university students.

Methylphenidate promotes the interaction between motor cortex facilitation and attention in healthy adults: A combined study using event-related potentials and transcranial magnetic stimulation

OBJECTIVE

This study investigated simultaneously the impact of methylphenidate (MPH) on the interaction of inhibitory and facilitative pathways in regions processing motor and cognitive functions.

METHOD

Neural markers of attention and response control (event-related potentials) and motor cortical excitability (transcranial magnetic stimulation) and their pharmacological modulation by MPH were measured simultaneously in a sample of healthy adults (n = 31) performing a cued choice reaction test.

RESULTS

Methylphenidate modulated attentional gating and response preparation processes (increased contingent negative variation) and response inhibition (increased nogo P3). N1, cue- and go-P3 were not affected by MPH. Motor cortex facilitation, measured with long-interval cortical facilitation, was increased under MPH in the nogo condition and was positively correlated with the P3 amplitude.

CONCLUSION

Methylphenidate seems particularly to enhance response preparation processes. The MPH-induced increased motor cortex facilitation during inhibitory task demands was accompanied by increased terminal response inhibition control, probably as a compensatory process.

Pharmacological neuroenhancement and the ability to recover from stress - a representative cross-sectional survey among the German population

BACKGROUND

Pharmacological neuroenhancement (PNE) refers to the use of psychoactive substances without doctor's prescription to enhance cognitive performance or to improve mood. Although some studies have reported that drugs for PNE are also being used to cope with stressful life situations, nothing is known about the relationship of PNE and resilience, i.e. the ability to recover from stress. This study aimed at investigating the relationship of PNE and resilience in the first representative population sample.

METHODS

A cross-sectional survey in a representative sample of 1128 adults (age ≥ 18 yrs.) living in Germany was conducted. The use of PNE and related attitudes, perceptions and behaviours were assessed by structured interviews and self-report questionnaires. Stepwise logistic regression with backward elimination was conducted to identify potential risk factors for PNE use.

RESULTS

Lifetime prevalence for the use of stimulating prescription drugs without medical indication was 4.3%, 10.2% for stimulating illicit drugs, 20.3% for mood modulating prescription drugs, and 23.4% for cannabis. Coping with stressful situations was more frequently reported as underlying motive for using stimulant or mood modulating prescription drugs than stimulating illicit drugs or cannabis. The individual perceived stress increased the risk of using stimulating prescription drugs (OR: 2.86; 95% Cl: 1.49-5.46) and the individual ability to recover from stress decreased the risk of using any substance for PNE and especially mood modulating prescription drugs (OR: .62; 95% Cl: .47-.81).

CONCLUSIONS

The non-medical use of prescription drugs for PNE appears to be more prevalent in subjects who are less resilient to stress. Tailored resilience interventions that improve the ability to adapt to and recover from stressors may prevent the use of prescription medication for PNE. Further research should disentangle the association between psychological resilience and PNE as well as examine the efficacy of resilience interventions in the prevention of PNE.

Moral attitudes and willingness to enhance and repair cognition with brain stimulation

BACKGROUND

The availability of technological means to enhance and repair human cognitive function raises questions about the perceived morality of their use. However, we have limited knowledge about the public's intuitive attitudes toward uses of brain stimulation. Studies that enlighten us about the public's willingness to endorse specific uses of brain stimulation on themselves and others could provide a basis to understand the moral psychology guiding intuitions about neuromodulation and opportunities to inform public education and public policy.

OBJECTIVE

Hypothesis: We expected that subjects would be less willing to enhance or repair cognitive functions perceived as more "core" to "authentic" self-identity, prioritize brain stimulation uses for themselves, and more willing to enhance "core" functions in others. Across specific hypothetical uses, we expected the moral acceptability of specific uses to be associated with subjects' willingness to endorse them.

METHODS

We administered two surveys to the public in which subjects were asked to report how willing they would be to enhance or repair specific cognitive abilities using a hypothetical brain stimulation device called "Ceremode".

RESULTS

Among 894 subjects, we found that subjects were more willing to use technologies to repair other people than themselves. They were most inclined to repair core functions in others. Subjects' ratings of the moral acceptability of specific uses was related to their reported willingness to use brain stimulation.

CONCLUSION

Moral acceptability is related to the public's willingness to use brain stimulation. These findings suggest that the public endorses a generous approach to applying brain stimulation for cognitive gains in others. Further, this study establishes a basis to guide moral psychological studies of cognitive modification and social processes that guide attitudes toward and uses of brain stimulation.

Using coffee to compensate for poor sleep: Impact on vigilance and implications for workplace performance

Poor sleep negatively impacts vigilance and is associated with reduced well-being and work productivity. While many individuals depend on caffeine to counteract the cognitive consequences of poor sleep and restore optimal work performance, few studies have naturalistically evaluated this strategy. This study examined the effects of coffee on vigilance, comparing individuals based on recent sleep quality. Sixty-nine participants completed two randomized, counterbalanced trials consisting of 237 ml water or coffee (100 mg caffeine), followed by a continuous performance test assessing vigilance at 30, 90, and 120 min. While coffee improved and stabilized reaction time at all three assessments regardless of recent sleep history, its effects on omission and commission errors were seen only at 90 min; coffee increased commission errors and only partially reduced omission errors in individuals reporting poor sleep quality. The use of coffee to combat poor sleep may therefore be detrimental in situations requiring inhibitory control.

Maternal Caffeine Consumption during Pregnancy and Behavioral Disorders in 11-Year-Old Offspring: A Danish National Birth Cohort Study

OBJECTIVE

To examine the association between maternal caffeine consumption from coffee and tea during pregnancy and offspring behavioral disorders.

STUDY DESIGN

We studied 47 491 children enrolled in the Danish National Birth Cohort between 1996 and 2002. Data on maternal coffee and tea consumption was collected at 15 and 30 weeks of gestation. When the child was 11 years old, the Strength and Difficulties Questionnaire was filled in by children, parents, and teachers. We estimated risk ratios (RRs) for offspring behavioral disorders.

RESULTS

At 15 weeks of gestation 3% and 4% of the pregnant women consumed ≥8 cups/d of coffee or tea, respectively. Maternal coffee consumption ≥8 cups/d at 15 weeks of gestation was associated with increased risk of hyperactivity-inattention disorder (RR 1.47; 95% CI 1.18-1.83), conduct-oppositional disorders (RR 1.22; 95% CI 1.01-1.48), and any psychiatric disorder (RR 1.23; 95% CI 1.08-1.40). Maternal tea consumption ≥8 cups/d at 15 weeks of gestation was associated with increased risk of anxiety-depressive disorders (RR 1.28; 95% CI 1.09-1.52) and any psychiatric disorder (RR 1.24; 95% CI 1.11-1.40). An increased risk of hyperactivity-inattention disorder was observed with increasing daily caffeine consumption at 15 weeks of gestation.

CONCLUSION

High maternal caffeine consumption from coffee and tea at 15 weeks of gestation was associated with behavioral disorders in 11-year-old offspring. We hypothesize that caffeine exposure may affect the fetal brain and program for behavioral disorders later in life. The fetal brain seems to be more sensitive to caffeine exposure at 15 weeks of pregnancy compared with 30 weeks of gestation.

Mixed-amphetamine salts expectancies among college students: Is stimulant induced cognitive enhancement a placebo effect?

INTRODUCTION

Non-medical use of prescription stimulants for cognitive enhancement in college students is increasing, despite evidence showing little benefit in non-clinical populations. The balanced placebo design (BPD) was used to independently evaluate the pharmacologic versus expectancy effects of mixed amphetamine salts on cognitive performance among a non-clinical sample of college-aged students.

METHOD

Participants were screened and excluded for ADHD and other psychopathologies. A non-clinical sample (N=32) completed four two-hour laboratory sessions and were administered a neurocognitive battery in each session. Medication Assignment (10mg mixed-amphetamine salt (Adderall™) versus placebo) was crossed with Instructional Set (deception versus truth). A within-subjects design was used, such that all participants experienced each of the four conditions of the BPD during one of the four laboratory sessions.

RESULTS

Participants performed no better than chance in identifying whether they received stimulant or placebo (Belief about Medication Assignment; 47% agreement; κ=-0.047, p=0.590). Participants showed improvement on only two of 31 subtests during active medication. Expecting and receiving stimulants was associated with improved cognitive performance. However, expecting placebo was associated with worse cognitive performance, regardless of the type of medication given.

DISCUSSION

This study demonstrated that although non-medical use of stimulants does not enhance cognition, expectancies prominently influence cognitive performance. Participants who believed they received active medication both subjectively rated themselves as performing better and objectively performed better on a minority of subtests, independent of medication state.

Methylphenidate Enhances Early-Stage Sensory Processing and Rodent Performance of a Visual Signal Detection Task

Methylphenidate (MPH) is used clinically to treat attention-deficit/hyperactivity disorder (ADHD) and off-label as a performance-enhancing agent in healthy individuals. MPH enhances catecholamine transmission via blockade of norepinephrine (NE) and dopamine (DA) reuptake transporters. However, it is not clear how this action affects neural circuits performing cognitive and sensorimotor functions driving performance enhancement. The dorsal lateral geniculate nucleus (dLGN) is the primary thalamic relay for visual information from the retina to the cortex and is densely innervated by NE-containing fibers from the locus coeruleus (LC), a pathway known to modulate state-dependent sensory processing. Here, MPH was evaluated for its potential to alter stimulus-driven sensory responses and behavioral outcomes during performance of a visual signal detection task. MPH enhanced activity within individual neurons, ensembles of neurons, and visually-evoked potentials (VEPs) in response to task light cues, while increasing coherence within theta and beta oscillatory frequency bands. MPH also improved reaction times to make correct responses, indicating more efficient behavioral performance. Improvements in reaction speed were highly correlated with faster VEP latencies. Finally, immunostaining revealed that catecholamine innervation of the dLGN is solely noradrenergic. This work suggests that MPH, acting via noradrenergic mechanisms, can substantially affect early-stage sensory signal processing and subsequent behavioral outcomes.

Methylphenidate, modafinil, and caffeine for cognitive enhancement in chess: A double-blind, randomised controlled trial

Stimulants and caffeine have been proposed for cognitive enhancement by healthy subjects. This study investigated whether performance in chess - a competitive mind game requiring highly complex cognitive skills - can be enhanced by methylphenidate, modafinil or caffeine. In a phase IV, randomized, double-blind, placebo-controlled trial, 39 male chess players received 2×200mg modafinil, 2×20mg methylphenidate, and 2×200mg caffeine or placebo in a 4×4 crossover design. They played twenty 15-minute games during two sessions against a chess program (Fritz 12; adapted to players' strength) and completed several neuropsychological tests. Marked substance effects were observed since all three substances significantly increased average reflection time per game compared to placebo resulting in a significantly increased number of games lost on time with all three treatments. Treatment effects on chess performance were not seen if all games (n=3059) were analysed. Only when controlling for game duration as well as when excluding those games lost on time, both modafinil and methylphenidate enhanced chess performance as demonstrated by significantly higher scores in the remaining 2876 games compared to placebo. In conjunction with results from neuropsychological testing we conclude that modifying effects of stimulants on complex cognitive tasks may in particular result from more reflective decision making processes. When not under time pressure, such effects may result in enhanced performance. Yet, under time constraints more reflective decision making may not improve or even have detrimental effects on complex task performance.

Modafinil alters decision making based on feedback history - a randomized placebo-controlled double blind study in humans

Modafinil is becoming increasingly popular as a cognitive enhancer. Research on the effects of modafinil on cognitive function have yielded mixed results, with negative findings for simple memory and attention tasks and enhancing effects for more complex tasks. In the present study we examined whether modafinil, due to its known effect on the dopamine level in the striatum, alters feedback-related choice behaviour. We applied a task that separately tests the choice of previously rewarded behaviours (approach) and avoidance of previously punished behaviours. 18 participants received a single dose of 200 mg modafinil. Their performance was compared to a group of 22 participants who received placebo in a double-blind design. Modafinil but not placebo induced a significant bias towards approach behaviour as compared to the frequency of avoidance behaviour. General attention, overall feedback-based acquisition of choice behaviour and reaction times in high vs low conflict choices were not significantly affected by modafinil. This finding suggests that modafinil has a specific effect on dopamine-mediated choice behaviour based on the history of feedback, while a contribution of noradrenaline is also conceivable. The described change in decision making cannot be considered as cognitive enhancement, but might rather have detrimental effects on decisions in everyday life.

Sensitivity of Quantitative Signal Detection in Regards to Pharmacological Neuroenhancement

Pharmacological neuroenhancement (PNE) is a form of abuse and has not yet been addressed by methods of pharmacovigilance. In the present study, we tested if quantitative signal detection may be sensitive in regards to PNE. We evaluated the risk of drug abuse and dependence (DAAD) related to substances that are known to be used for PNE and divided this group into agents with (methylphenidate) and without a known abuse potential outside the field of PNE (atomoxetine, modafinil, acetylcholine esterase inhibitors, and memantine). Reporting odds ratios (RORs) were calculated using a case/non-case approach based on global and country-specific drug safety data from the Uppsala Monitoring Centre (UMC). Both control substances (diazepam and lorazepam) and methylphenidate were statistically associated with DAAD in all datasets (except methylphenidate in Italy). Modafinil was associated with DAAD in the total dataset (ROR, 2.7 (95% confidence interval (CI), 2.2-3.3)), Germany (ROR, 4.6 (95% CI, 1.8-11.5)), and the USA (ROR, 2.0 (95% CI, 1.6-2.5)). Atomoxetine was associated with DAAD in the total dataset (ROR, 1.3 (95% CI, 1.2-1.5)) and in the UK (ROR, 3.3 (95% CI, 1.8-6.1)). Apart from memantine, which was associated with DAAD in Germany (ROR, 1.8 (95% CI, 1.0-3.2)), no other antidementia drug was associated with DAAD. Quantitative signal detection is suitable to detect agents with a risk for DAAD. Its sensitivity regarding PNE is limited, although atomoxetine and modafinil, which do not have a known abuse potential outside PNE, and no antidementia drugs, whose use in PNE is presumably low, were associated with DAAD in our analysis.

From Clinical Application to Cognitive Enhancement: The Example of Methylphenidate

Methylphenidate (MPD) is a central nervous system (CNS) stimulant, which belongs to the phenethylamine group and is mainly used in the treatment of attention deficit hyperactive disorder (ADHD). However, a growing number of young individuals misuse or abuse MPD to sustain attention, enhance intellectual capacity and increase memory. Recently, the use of MPD as a cognitive enhancement substance has received much attention and raised concerns in the literature and academic circles worldwide. The prescribing frequency of the drug has increased sharply as consequence of the more accurate diagnosis of the ADHD and the popularity of the drug itself due to its beneficial short-term effect. However, careful monitoring is required, because of possible abuse. In this review different aspects concerning the use of MPD have been approached. Data showing its abuse among college students are given, when the drug is prescribed short term beneficial effects and side effects are provided; moreover studies on animal-models suggesting long lasting negative effects on healthy brains are discussed. Finally, emphasis is given to the available formulations and pharmacology.

Pharmacological Neuroenhancement: teachers' knowledge and attitudes-Results from a survey study among teachers in Germany

Background

Pharmacological neuroenhancement (PN) is a topic of increasing importance. Its prevalence rates range from 1 % to more than 20 %. Students are a group that shows exceptionally high prevalence rates. However, little is known about teachers’ knowledge, management, attitudes and ethical judgements regarding PN.

Methods

A web-based survey containing 40 closed questions was developed. All teachers working at all private and public schools in Mecklenburg-Vorpommern, a state in northeastern Germany, were invited to participate after their respective school offices were contacted by telephone, email and mail.

Results

In total, 255 teachers participated in the survey. Of those, 73.3 % had already heard about PN in general, and 68.2 % had heard about PN in students. Their sources of knowledge were digital media such as TV (73.8 %) and the internet (40.6 %) and print media (64.7 %); their own students informed 29.9 % of the teachers about PN in general and 35.6 % of them about PN among students. Furthermore, 34.9 % of the surveyed teachers were convinced that PN substance use was ineffective in general, and 51.8 % of the surveyed teachers believed that PN substances were ineffective in achieving better grades. Only 1.2 % thought that none of the so-called PN substances could lead to addiction, and 37.6 % would classify PN substance use as general drug misuse. The highest values regarding risk of addiction were observed for illicit drugs. The prevalence of PN substance use was evaluated to be very low and to be significantly higher in male, highly skilled and college/university students. In total, 1.6 school lessons per year were used to discuss PN. Finally, 55.7 % of the surveyed teachers believed that performance-enhancing substances should be forbidden at schools.

Conclusion

Teachers, as an integral part of the education of children and adolescents, often know about PN substances and mostly refuse their use being afraid about the risk of addiction. However, regarding effects as well as side effects of PN substances, teachers have very different opinions. Furthermore, they seem to underestimate the prevalence among their students and broach the topic infrequently. Teachers should be sensitized for high prevalence rates and should broach the topic of PN more frequently to their students to prevent potential misuse of PN substances.

Classics in Chemical Neuroscience: Methylphenidate

As the first drug to see widespread use for the treatment of attention deficit hyperactivity disorder (ADHD), methylphenidate was the forerunner and catalyst to the modern era of rapidly increasing diagnosis, treatment, and medication development for this condition. During its often controversial history, it has variously elucidated the importance of dopamine signaling in memory and attention, provoked concerns about pharmaceutical cognitive enhancement, driven innovation in controlled-release technologies and enantiospecific therapeutics, and stimulated debate about the impact of pharmaceutical sales techniques on the practice of medicine. In this Review, we will illustrate the history and importance of methylphenidate to ADHD treatment and neuroscience in general, as well as provide key information about its synthesis, structure-activity relationship, pharmacological activity, metabolism, manufacturing, FDA-approved indications, and adverse effects.

Drugs As Instruments: Describing and Testing a Behavioral Approach to the Study of Neuroenhancement

Neuroenhancement (NE) is the non-medical use of psychoactive substances to produce a subjective enhancement in psychological functioning and experience. So far empirical investigations of individuals' motivation for NE however have been hampered by the lack of theoretical foundation. This study aimed to apply drug instrumentalization theory to user motivation for NE. We argue that NE should be defined and analyzed from a behavioral perspective rather than in terms of the characteristics of substances used for NE. In the empirical study we explored user behavior by analyzing relationships between drug options (use over-the-counter products, prescription drugs, illicit drugs) and postulated drug instrumentalization goals (e.g., improved cognitive performance, counteracting fatigue, improved social interaction). Questionnaire data from 1438 university students were subjected to exploratory and confirmatory factor analysis to address the question of whether analysis of drug instrumentalization should be based on the assumption that users are aiming to achieve a certain goal and choose their drug accordingly or whether NE behavior is more strongly rooted in a decision to try or use a certain drug option. We used factor mixture modeling to explore whether users could be separated into qualitatively different groups defined by a shared "goal × drug option" configuration. Our results indicate, first, that individuals' decisions about NE are eventually based on personal attitude to drug options (e.g., willingness to use an over-the-counter product but not to abuse prescription drugs) rather than motivated by desire to achieve a specific goal (e.g., fighting tiredness) for which different drug options might be tried. Second, data analyses suggested two qualitatively different classes of users. Both predominantly used over-the-counter products, but "neuroenhancers" might be characterized by a higher propensity to instrumentalize over-the-counter products for virtually all investigated goals whereas "fatigue-fighters" might be inclined to use over-the-counter products exclusively to fight fatigue. We believe that psychological investigations like these are essential, especially for designing programs to prevent risky behavior.

A Comparison of the Cheater Detection and the Unrelated Question Models: A Randomized Response Survey on Physical and Cognitive Doping in Recreational Triathletes

Purpose

This study assessed the prevalence of physical and cognitive doping in recreational triathletes with two different randomized response models, that is, the Cheater Detection Model (CDM) and the Unrelated Question Model (UQM). Since both models have been employed in assessing doping, the major objective of this study was to investigate whether the estimates of these two models converge.

Material and Methods

An anonymous questionnaire was distributed to 2,967 athletes at two triathlon events (Frankfurt and Wiesbaden, Germany). Doping behavior was assessed either with the CDM (Frankfurt sample, one Wiesbaden subsample) or the UQM (one Wiesbaden subsample). A generalized likelihood-ratio test was employed to check whether the prevalence estimates differed significantly between models. In addition, we compared the prevalence rates of the present survey with those of a previous study on a comparable sample.

Results

After exclusion of incomplete questionnaires and outliers, the data of 2,017 athletes entered the final data analysis. Twelve-month prevalence for physical doping ranged from 4% (Wiesbaden, CDM and UQM) to 12% (Frankfurt CDM), and for cognitive doping from 1% (Wiesbaden, CDM) to 9% (Frankfurt CDM). The generalized likelihood-ratio test indicated no differences in prevalence rates between the two methods. Furthermore, there were no significant differences in prevalences between the present (undertaken in 2014) and the previous survey (undertaken in 2011), although the estimates tended to be smaller in the present survey.

Discussion

The results suggest that the two models can provide converging prevalence estimates. The high rate of cheaters estimated by the CDM, however, suggests that the present results must be seen as a lower bound and that the true prevalence of doping might be considerably higher.