Neuroenhancement
Neuroenhancement refers to the use of drug medication to enhance certain brain processes in healthy persons who do not have any mental illness.[1] [2][3][4] [5] Along with cognitive functioning, neuroenhancements have also attempted to help people with lack of social skills and empathy. Such neuroenhancement drugs try to increase oxytocin and decrease cortisol levels helping people better their communication and social interaction skills.[4]
The abuse of neuroenhancement drugs without clinical consent poses a pressing issue. Currently, there is not enough information to conclude that neuroenhancement drugs have an enhancing effect on healthy individuals. Determining the correct dosage is crucial as too little or too much of the drug may have no or even adverse effects.[1] Guidelines for the regulation of these drugs need to be established before the abuse of such drugs goes beyond regulatory control.[4]
Neuroenhancements are a specific subset of nootropics. Unlike many nootropics that are illegal, neuroenhancements require prescription for usage. Neuroenhancement drugs are also intended for treating patients suffering from neurological disorders, but recent years have seen an increasing number of healthy individuals requesting neuroenhancement drug prescriptions.[6][7] Many common nootropics however, such as racetam, vinpocetine, and phosphatidylserine, are intended to increase the cognitive performance of healthy individuals and are illegal.[5]
Drug neuroenhancement
Modafinil
Modafinil is wakefulness promoting drug that decreases fatigue, increases vigilance, reduces daytime sleepiness, and improves mood.[3][4][8] Modafinil is currently licensed for treating patients with disorders such as narcolepsy, sleep apnea, and shift-work sleep disorder.[1][4] This drug also seems promising in the treatment of depression and bipolar disorder.[4] Modafinil is currently being used by United States Air Force personnel for missions of great duration in an attempt to decrease fatigue amongst aircrew. It has become more popular amongst the general public. In an online poll conducted by Nature magazine, 8.8% of 1400 corresponding readers admitted use of modafinil for non-medical reasons. Their reasoning behind its use was for increasing concentration and focus on a specific task or to counteract sleep deficit and jetlag.[1] A comparison between the sales of modafinil to the number of patients revealed a disproportionate ratio, indicating high abuse.[1]
Modafinil had moderate enhancing effects on increasing attention in individuals who were not sleep deprived. Effects on sleep deprived individuals were more apparent; a single dose resulted in enhanced wakefulness, executive functions, and memory.[8] In the case of sustained sleep deprivation, repeated intake of modafinil helped individuals maintain higher levels of wakefulness than the placebo, but did not help attention and executive function.[1][8] Since the majority of these trials were conducted on military personnel, further research needs to be conducted on the effects of modafinil on the general population. Modafinil may impair one’s self-monitoring ability. A common trend found in research studies indicated that participants rated their performances on cognitive tests higher than it actually was, suggesting “overconfidence” effect.[1] Modafinil showed improvement in spatial working memory, planning and decision making, motivation, and visual pattern recognition memory following a delay. [9] Subjective ratings of the participants in this experiment demonstrated that those taking modafinil rated each task performed significantly higher in terms of enjoyment.[9]
Modafinil is becoming increasingly popular amongst the general population. Apart from a consumer’s want to increase his neurological performance, there are financial incentives for manufacturers as well. Modafinil has a market share of more than $700 million dollars a year, indicating a high degree of off-label use.[3] Modafinil is also one of the more easily available neuroenhancement drugs in the market today. In Asian countries, modafinil can even be bought online.[3] Modafinil first came into attention when world champion runner Kelli White was tested positive for illegally consuming modafinil in the Athletics World Championship in 2003, resulting in the loss of her 2 gold medals.[3]
Methylphenidate
Methylphenidate (MPH) is a stimulant that is used to treat attention-deficit hyperactivity disorder (ADHD). MPH is known to be highly abused by the general population, especially college students.[1][3] In an online poll conducted by Nature magazine, 12.4% of 1400 corresponding readers admitted use of MPH for non-medical reasons. Their reasoning behind its use was for increasing concentration, sleep deficit, and jetlag.[1]
A comparison between the sales of MPH to the number of patients revealed a disproportionate ratio, indicating high abuse.[1] MPH is believed to have a positive effect for memory consolidation, but studies have not been able to conclusively verify this claim.[1] [8] Popular opinion that MPH enhances attention could not be verified.[1][8] Studies of MPH have reported improved problem solving skills. However, when these studies were repeated to replicate the results, the placebo group scored higher, indicating that MPH may even impair performance.[3]
These inconclusive, and generally negative, results for memory enhancement are insufficient to explain the use of MPH for non-medical reasons. Users may have motives other than genuine neuroenhancement that propels its illegal use, such as subjective and recreational effects.[1] The lack of any result, positive or negative, indicated that the 10–20 mg dosage may be too low for the drug.[1] Further studies need to be conducted, looking at different doses of MPH.[1][8]
Memantine
Memantine is a NMDA receptor antagonist and is used to treat patients with moderate to severe Alzheimer’s disease, but is also abused as a neuroenhancement drug.[2] Studies conducted on memantine were unable to conclusively verify neuroenhancement capability of the drug. Since most of these studies were single dose tests of memantine, it is possible that these drugs would only show some effect, positive or negative, after continuous intake. Until then, single dose studies of memantine are not enough to reveal the drug’s actual potential.[2]
Donepezil
Donepezil is an acetylcholinesterase inhibitor (AChEI) that is used to treat patients with mild to moderate Alzheimer’s disease. While many AChEI’s could be potential neuroenhancement substances, donepezil is the most commonly used AChEI’s by the general population due to its widespread patients use for treating Alzheimer’s disease.[2]
Most studies on donepezil are unable to conclusively verify neuroenhancement capability of the drug.[2] In such studies, it was seen participants that took donepezil scored higher than those that took the placebo. Donepezil’s helps individuals retain training tasks, verbal memory, and episodic memory.[2] In sleep deprivation studies, while donepezil had no effect on well rested patients, it had a positive effect on patients with 24 hours of sleep deprivation. Such patients benefited from increased memory performance and attention that would otherwise be deficit in such sleep deprived conditions.[2] This effect however, was only seen in individuals whose performance declined significantly due to sleep deprivation.[2]
Non-drug neuroenhancement
Transcranial direct current stimulation
While neuroenhancement drugs are a potential method for cognitive performance enhancement, Transcranial direct current stimulation (tDCS) over the motor cortex (MC) is being seen as another potential method.[10] Although it was originally intended to help patients with brain injuries such as stroke, there has been a lot of interest in the last few years on tDCS’s capabilities for healthy individuals as well. Recent studies have already shown improved neuroplasticity from tDCS to facilitate motor learning in young humans, and it may be possible to apply this method to the older segment of the workforce as well.[10]
Stimulating higher cognitive functions of the brain, such as the language function, with tDCS in one study resulted in improved word retrieval. tDCS works by enhancing the connectivity in a given stimulated network, providing neural efficiency in highly specific brain areas critical for task performance. [11] During this time, fMRI images also showed reduced activity in the semantic retrieval processes, suggesting more efficient processing in task-critical areas of the brain.[11] Reduced activity in circumscribed task-related areas has been attributed to consolidation of motor learning and superior memory performance. New research in tDCS is trying to localize the stimulation to affect the desired subset of highly specific task-relevant neurons.[11]
Deep brain stimulation
Deep brain stimulation (DBS) is another form of neuroenhancement. Unlike tDCS, though, DBS involves the implantation of a medical device, and is restricted for use for only a few, severe diseases such as Parkinson's disease and dystonia. [12] In one study, DBS improved movement by 39%, reduced disability by 38%, and improved quality of life by 30% for patients suffering from dystonia over a course of 3 months.[12] The patients had a reduction in dystonia symptoms by 50%.[12] Improvement was noticeable within hours to days after DBS application. The benefits of DBS as of now are far more than those of high-dosage trihexphenidyl, a powerful drug used in the treatment for dystonia.
Side effects
Neuroenhancements drugs are well tolerated by healthy humans.[1][2] These drugs are already in mainstream use to treat patients with different kinds of psychiatric disorders. Since most of the information on neuroenhancements and its capabilities are drawn from research experiments, the best way to determine adverse effects are drop-out rates and subjective rating.[1][2] The drop-out rates were minimal or non-existent for donepezil, memantine, MPH, and modafinil.[1][2] In the drug trials, participants reported the following adverse reactions to the consumption of donepezil, memantine, MPH, or modafinil: gastrointestinal complaints (nausea), headache, dizziness, nightmares, anxiety, drowsiness, nervousness, restlessness, sleep disturbances, and insomnia.[2] The side effects normally ceased in the course of treatment.[2] While there were no reported side effects from DBS, 18% of the patients suffered from device related complications such as infections due lead dislodgment or breakage.[12]
Ethical, social and legal Issues
Neuroenhancement is often seen analogous to the issue of doping in sports. [13] A common concern raised is an unfair advantage of people who consume enhancing drugs over people who don’t. Many athletes, however, feel that the only way for them to win against athletes that take performance enhancing drugs(PED) is for them to take PED’s as well; a similar thought process has developed within the general population in regard to people that consume neuroenhancement drugs.[13] In a research study of 18-34 year olds, 50% of them had little or no objection to the concept of doping.[13] Students, in particular, often feel that cognitive neuroenhancers are acceptable.[13] However, parents and healthcare providers are concerned about the safety and well-being of those that consume neuroenhancement.[13]
In a recent article published by Jayne C Lucke, the concept of neuroenhancement is compared to Viagra. The author states that “recreational users of Viagra had lower confidence in their ability to achieve an erection than non-users, even though they had significantly better erectile function. They become psychologically dependent on these drugs.” The author believes a similar trend can be seen neuroenhancement users.[13] The author goes on to argue about how expectation, especially in students that are the general force, differs vastly on what is considered normal or good performance. Many argue that the only option for regulation of neuroenhancements is to allow it to everyone, thus minimizing cheating. Banning the drugs, on the other hand, may have detrimental consequences to society. Not only would it create a black market, amplifying issues caused by illicit use, it would also increase the cost to society from enforcing the law.[13] Neuroenhancement drugs need to be assessed further for their merits and adverse effects, making it easier for policy makers to make a call on the regulation of such drugs.[8]
Scope for cognitive enhancement
Proponents of cognitive enhancement have argued that there are vast potential benefits for the workforce, especially for the older segment. [10] Due to advances in medical technology over the last century, the human life expectancy has increased significantly. Demographics for developed countries indicate rapid growth of the older segment of the workforce. Advancing age generally shows a pattern in the reduction of the ability to acquire new skills, but integration in the industry today requires employees to be able to acquire and retain new skills more than ever before.[10]
Opinion on neuroenhancements
General public
The opinion of the general public on the issue of neuroenhancement is scattered.[6][13] In general, the younger population under the age of 25 feel that neuroenhancements are acceptable or that the decision lies in the hand of that individual. Healthcare officials and parents feel concerned due to safety factors, lack of complete information on these drugs, and possible irreversible adverse effects.[13]
Studies have estimated that between 7-9% of the college population in the United States consumes neuroenhancement drugs. Some studies estimate this figure to be as high as 12% or even 20%.[6] Students primarily attribute consumption of these drugs for increased concentration, improved alertness, or to “get high”.[6][13] Neuroenhancement drug users rated the positive potential of neuroenhancement drugs higher than non-users, and rated the adverse effects of these drugs lower than non-users, showing more confidence in the result of these drugs. In a survey of 1324 German students, 32% of participants that do not consume neuroenhancement drugs felt they had positive cognitive effects while 12% felt they had a relaxation effect.[6] In contrast, 54% of participants that do consume neuroenhancement drugs felt they had a positive cognitive effect while 25% felt they had a relaxation effect.
The need to remain “alert” and “focused” can also been seen in the trend of caffeine consumption. The caffeine consumption for both students and the general population of the US is around 90%.[6] [7] Students who consume neuroenhancements also had a higher frequency of consuming psychoactive lifestyle drugs such as cannabis. This demonstrates a trend of psychological addiction amongst neuroenhancement users.[6]
Physicians
Physicians play an important role in determining the potential abuse of neuroenhancing drugs. While some neuroenhancing drugs do not require a prescription and are easily available, others that require prescription are up to the discretion of the physician. Most physicians would agree that their criteria to determine whether or not a dysfunction should be considered a disease is if the patient indicates subjective suffering and/or negative consequences for everyday ability to work.[5] Physicians, however, stated that they do not prescribe medication without a clear indication of such a dysfunction.[5]
References
- ↑ 1.0 1.1 1.2 1.3 1.4 1.5 1.6 1.7 1.8 1.9 1.10 1.11 1.12 1.13 1.14 1.15 1.16 1.17 Repantis, Dimitris; Schlattmann, Peter (2010). "Modafinil and methylphenidate for neuroenhancement in healthy individuals: A systematic review". Pharmacological Research 62 (3): 187–206. doi:10.1016/j.phrs.2010.04.002. PMID 20416377.
- ↑ 2.0 2.1 2.2 2.3 2.4 2.5 2.6 2.7 2.8 2.9 2.10 2.11 2.12 Repantis, Dimitris (June 2010). "Acetylcholinesterase inhibitors and memantine for neuroenhancement in healthy individuals: A systematic review". Pharmacological Research 61 (6).
- ↑ 3.0 3.1 3.2 3.3 3.4 3.5 3.6 Normann, Claus (November 2012). "Neuroenhancement: status quo and perspectives". European Archives of Psychiatry and Clinical Neuroscience.
- ↑ 4.0 4.1 4.2 4.3 4.4 4.5 Normann, Claus (November 2012). "Neuroenhancement strategies for psychiatric disorders: rationale, status quo and perspectives". European Archives of Psychiatry and Clinical Neuroscience 262.
- ↑ 5.0 5.1 5.2 5.3 Ott, R. (2012). "Neuroenhancement - perspectives of Swiss psychiatrists and general practitioners". Swiss Medical Weekly 142.
- ↑ 6.0 6.1 6.2 6.3 6.4 6.5 6.6 Eickenhorst, Patrick (2012). "Neuroenhancement Among German University Students: Motives, Expectations, and Relationship with Psychoactive Lifestyle Drugs". Journal of Psychoactive drugs 44 (5): 418–427. doi:10.1080/02791072.2012.736845. PMID 23457893.
- ↑ 7.0 7.1 Olsen, Nicole (2013). Caffeine Consumption Habits and Perceptions among University of New Hampshire Students.
- ↑ 8.0 8.1 8.2 8.3 8.4 8.5 8.6 Ragan, Ian (February 2013). "What should we do about student use of cognitive enhancers? An analysis of current evidence". Neuropharmacology 65: 588–595.
- ↑ 9.0 9.1 Muller, U. "on non-verbal cognition, task enjoyment and creative thinking in healthy volunteers". Effects of modafinil on non-verbal cognition, task enjoyment and creative thinking in healthy volunteers 64: 490–494.
- ↑ 10.0 10.1 10.2 10.3 Zimerman, Maximo (2013). "Neuroenhancement of the Aging Brain: Restoring Skill Acquisition in Old Subjects". Annals of neurology 73 (1): 10–15. doi:10.1002/ana.23761. PMID 23225625.
- ↑ 11.0 11.1 11.2 Meinzer, Marcus (2012). "Electrical brain stimulation improves cognitive performance by modulating functional connectivity and task-specific activation". The Journal of Neuroscience 32 (5): 1859–1866. doi:10.1523/JNEUROSCI.4812-11.2012. PMID 22302824.
- ↑ 12.0 12.1 12.2 12.3 Kupsch, Andreas (2006). "Pallidal Deep-Brain Stimulation in Primary Generalized or Segmental Dystonia". New England Journal of Medicine 355 (19): 1978–1990. doi:10.1056/NEJMoa063618. PMID 17093249.
- ↑ 13.0 13.1 13.2 13.3 13.4 13.5 13.6 13.7 13.8 13.9 Lucke, Jayne C.; Bell, Stephanie K.; Patridge, Bradley J.; Hall, Wayne D. (2011). "Academic Doping or Viagra for the brain?". EMBO Rep 12 (3): 197–201. doi:10.1038/embor.2011.15. PMC 3059919. PMID 21311560.