Our Brain Is Being Beaten

With the increase in computer performance and accessibility of personal computing, most jobs require computer skills as part of their work. According to an analysis done by the US Department of Labor and the Brookings Institution from 2002 to 2016, 517 out of the 545 most common US occupations have seen a rapid increase in digitization and desire for computer skills [1]. The computer has made our jobs much simpler and, in some ways, made human crystallized intelligence, knowledge acquired by memory and experience, laughable [2]. A computer’s memory can hold tens of billions of bytes, while most of us can’t seem to remember our own passwords.

This effectively has changed the working environment for many Americans. Many of our jobs now don’t require a simple rinse-and-repeat of the same movement or information, such as cashiers, factory workers, and truck drivers; we have self-checkouts, robots, and autonomous driving to take care of that. Thus, businesses nowadays don’t want to spend the extra resources to train a human the same information and movements that a computer can do at a lower cost, more accurately, and with a whole lot less complaining.

In response, our workforce is now shifting toward an emphasis on fluid intelligence, the ability to use critical thinking to solve problems with speed and efficiency [2]. However, this raises another issue: our aging population. The fastest-growing population segment in America is age 65 and older [3]. It is projected that by 2029, more than 20 percent of the total US population will be 65 and older and by 2056, the population 65 and older is projected to be larger than the population 18 and younger [3]. The decline of pensions and lower savings for retirees is forcing people to work longer when they would normally retire [4]. Consequently, the fastest-growing segment of our labor force is workers 65 and older, at an 11 percent growth in the next 5 years [5].

With a work environment valuing fluid intelligence more and more, how will older people cope? A study conducted at the University of Colorado presented fluid intelligence tasks to 196 participants ages 20 to 89, testing participants’ planning, decision making, reaction time, and critical thinking skills. The study showed that older participants’ ability to complete the tasks quickly and accurately was lower compared to younger participants and suggested that fluid intelligence declines with age [6]. This has implications on an older person’s ability to learn critical thinking skills for a new job. Some jobs require sustained, razor-sharp focus and have little margin for error, such as air traffic controllers, radar operators, paramedics, and pilots. We are experiencing great shortages of personnel in these jobs and seniors are generally advised not to do them. Moreover, people currently doing these jobs aren’t advised to stay for many years. Would it be helpful for individuals to find a way to let them work for longer, with less health implications and with less mistakes? As our fastest-growing segment of the workforce, we can’t leave older people behind. There must be a way to turn back the brain’s years, and have it work at peak performance.

Enter neuroenhancement, a newly developing field of neuroscience seeking to use pharmacological and non-pharmacological methods to enhance cognitive functioning and performance in healthy humans. These methods include drugs such as modafinil, methylphenidate, donepezil, and rolipram, as well as non-invasive brain stimulation methods such as transcranial direct current stimulation (tDCS). Government agencies, such as the National Institutes of Health and the US Department of Defense, as well as new startup companies, have begun sponsoring neuroenhancement research and are leading the way in making it safe and accessible for seniors [7]. Though neuroenhancement has brought up ethical debates, with arguments likening its use to doping in sports as well as fears of abuse, widening socioeconomic divides, and its potential implications on the skilled labor market, neuroenhancement still holds boundless potential. If successful, neuroenhancement can allow us to work longer with more focus, increase job accessibility, and keep us competitive in the workforce.

Neuroenhancement by Mouth

In order to help our aging workforce gain ground in the ever-digitizing and high-intensity work environment, we can increase cognitive performance by facilitating learning and increasing attention on the job. There exists numerous drugs known as nootropics, of varying legality, that help us achieve this. In the interest of your common, law-abiding senior looking for jobs, we will focus on the legal selection of pharmacological neuroenhancers and how they facilitate learning and increase attention.

As we get older, our ability to learn and remember new things slowly diminishes. This explains why it’s easier to learn a new language when young and it becomes much harder as we age. A study conducted on 2450 Americans ages 16-89 tested and scored each participant on tasks involving long- and short-term memory in linguistic, literary, and facial recognition contexts. It found that the median age of peak performance for each of these tasks ranged from 19 to 30 years old [8]. With the average life expectancy of Americans at 78.6 years, this figure is a grim reality that as we live longer and longer, and demand for work gets higher and higher, many won’t have the ability to learn new skills for new jobs [9]. Donepezil and rolipram, two drugs that directly target the brain’s neurological mechanisms for learning, may offer a solution to this dilemma.

Donepezil is a drug already approved for use in Alzheimer’s disease patients and works by inhibiting the enzyme acetylcholinesterase, which clears neurons and synapses of excess acetylcholine after a nerve impulse, in a process called reuptake [2]. Various studies have shown acetylcholine to promote learning. A study done on rhesus monkeys that interfered with acetylcholine supply to the hippocampus showed “severe impairment in learning visual scenes and object–reward associations” [10]. By inhibiting acetylcholine reuptake via acetylcholinesterase inhibition, donepezil effectively increases the effect of acetylcholine on our neurons, which facilitates our brains' ability to learn and make new associations. A Stanford University study testing the potential benefits of donepezil on non-Alzheimer’s subjects has already shown promise. Eighteen licensed pilots, with the average age of 52, were given a series of complex flight-simulation tasks to test reaction time, critical thinking, and decision making in the piloting setting. Nine pilots followed a 30-day donepezil treatment plan, with the other nine receiving placebos. The donepezil-assisted group “showed greater ability to retain the capacity to perform a set of complex simulator tasks than the placebo group” [11]. Donepezil is not yet approved for use outside of treating Alzheimer’s disease, but there is now a resurgence in interest in the drug due to its potential for neuroenhancement.

Like donepezil, rolipram is another drug being targeted for a transition into neuroenhancement usage.  It was originally developed as an antipsychotic and anti-inflammatory drug, but it has shown to facilitate learning and memory by increasing the production of cyclic-AMP response element-binding proteins (CREB), which promote long-term potentiation (LTP) [12]. LTP is the strengthening of synapses in response to repeated exposure to stimuli and is the basis of brain plasticity, the process in which our brain can change its structure and function over time. A study conducted on fruit flies with and without increased CREB levels found that fruit flies with increased CREB levels were quicker to learn the location of a food source than fruit flies with normal CREB levels.  Furthermore, high-CREB fruit flies learned the location of the food source within one trial while normal-CREB fruit flies took more than ten trials [12]. Another study researching the effects of rolipram on rats after a memory-impairing drug had been administered, has found that rolipram increased cyclic-AMP (cAMP) and CREB levels in the rats’ brains. The increased levels of cAMP and CREB facilitated  LTP, so much so that the memory deficit incurred by the administration of the memory-impairing drug had been completely recovered just one week after rolipram treatment [13]. Although studies on rolipram have shown great potential for neuroenhancement, it was discontinued in clinical trials due to its undesirable side effects on the gastrointestinal tract [14]. Research is now focused on drugs with a similar function and mechanism as rolipram as well as modifying rolipram itself to be safe enough to re-enter clinical trials and be approved for public use.

Learning and memory aren’t the only things that peak early and decline as we age. A study done at Ryerson University analyzed the performance of 24 young adults (ages 18 to 29) and 24 older adults (ages 60 to 76) in tasks designed to test one’s ability to be alerted by a stimulus, orient themselves to respond, and respond within a certain time. Older adults were found to have reduced alerting and reaction time when compared to their young adult counterparts [15]. It’s harder to catch an older person’s attention, which can cost them when our jobs require extra learning and become more based on critical thinking. Drugs that help heighten attention are among the most well-known and frequently used in the world. They are stimulants, a class of drugs that include anything from your daily cup of coffee to controlled substances such as cocaine and ecstasy. Two standout stimulants with approved medical uses and proven cognitive benefits are modafinil and methylphenidate.

Modafinil is prescribed to patients with narcolepsy and various other sleep disorders. Modafinil has also seen uses as a “go-pill” in the United States Air Force, allowing its use in pilots to ensure combat readiness and wakefulness [16]. Modafinil keeps us awake by partially blocking dopamine transporters in our neurons, which clear our synapses of excess dopamine after a nerve impulse [17]. By blocking dopamine transporters, modafinil effectively increases dopamine’s effects, which include motivation, arousal, and motor control, much like donepezil and acetylcholine. Modafinil’s mechanism of action can lead to addiction and dependence, which is why it is a controlled substance in the United States and only attainable with a prescription, though many doses are distributed and administered illegally. Research is being done in rats to discover potential neuroenhancing benefits with modafinil. One study found that rats given a single daily dose of a close variant of modafinil called CE-123 were shown to have heightened memory acquisition and retrieval compared to rats that weren’t given any CE-123 [17]. It is unclear what an effective dose for a human will be, and if modafinil variants can be more effective as a neuroenhancer. Despite this, modafinil is rising to prominence as one of the most promising neuroenhancers and one of the closest to widespread use.

Methylphenidate is one of the most well-known, most prescribed, and also most abused stimulants in the world. It’s commonly known by its brand name Ritalin and is used to treat narcolepsy and attention deficit hyperactivity disorder (ADHD). Methylphenidate is popular for abuse among college students, who seek to exploit the cognitive effects of the drug to increase academic performance [18]. The way that methylphenidate interacts with our brain and acts as a stimulant is similar to modafinil, with the addition of a norepinephrine reuptake inhibitory effect. Hence, methylphenidate increases the effect of dopamine and norepinephrine on the brain. Norepinephrine is responsible for preparing our brain and body for action and is integral to our fight-or-flight response. Comparatively, methylphenidate is more powerful and has a higher potential for addiction than modafinil. Methylphenidate also carries risks for overdose, with symptoms stemming from overstimulation of the central nervous system, including heart palpitations and convulsions [19]. Methylphenidate is placed under stricter regulation than modafinil at Schedule II, where it is grouped with drugs such as cocaine and fentanyl. Despite its reputation and current legal status, methylphenidate in low doses has shown potential in being a neuroenhancer. A study done on rats given a low dose (0.5-2.5 mg/kg of body weight) of methylphenidate and tasked with spatial reasoning and learning tasks showed “enhanced learning acquisition and memory retention”, while higher doses (exceeding 5 mg/kg of body weight) “impaired learning acquisition and memory retention” [18]. Further research is being conducted on how this dosage could apply to human use and how the risks of addiction could change as a result of a lower dose. Methylphenidate still has a lot of research in front of it and a stained reputation to reconcile with before having the chance to enter mainstream use, but its potential as a neuroenhancer is promising and interest surrounding it is rising.

Neuroenhancement As An “Electrifying” Experience

The nervous system functions electrochemically, and within the topic of neuroenhancement, the “chemical” portion tends to take center stage when we think about developing and testing new techniques. However, neuroenhancement through pharmacological means can be cumbersome and can be seen as a temporary and fleeting solution to enhancing cognition. For those seeking a more permanent method of neuroenhancement without having to worry about missed pills, side effects, or overdoses, there exist methods that focus on the brain and neurons as a purely electrical system.

Transcranial direct-current stimulation (tDCS) takes advantage of the brain’s electrical properties. Billions of neurons in our brain constantly change their electrical charges in response to impulses. tDCS works by fitting electrodes to the scalp and applying a weak direct current (0.5-2 mA) to stimulate neurons in the brain, increasing or decreasing neuronal excitability to the demands of the user [20]. Given its mechanism of action, tDCS is promising when applied to the elderly brain, which may not fire impulses driving learning, memory, critical reasoning, and executive functioning as fast as it used to. Studies have already shown that tDCS can improve specific cognitive functions when applied to specific brain regions. A study testing the effects of tDCS to the motor cortex found that older subjects (age 65 to 71) saw faster acquisition of a complex motor task as well as increased retention of that task 24 hours after tDCS was applied [21]. Another study applying tDCS to the prefrontal cortex found that older subjects (average age of 70) saw significant improvement in working memory tasks, though sample sizes were small and only consisted of women [22]. Furthermore, the effects of tDCS can last even after stimulation is over. One study using animal brain slices found that tDCS induces LTP in motor neurons after stimulation, creating a fast-tracked path for learning [23]. On a more practical front, tDCS is far more personalized than neuroenhancing drugs, since it can be customized to suit an individual’s unique brain structure rather than a “one dose fits all” drug. tDCS is also non-invasive, painless, and doesn’t require administration of any drugs. There are even numerous affordable devices available for purchase today which contain all the electrodes, batteries, and instructions needed to perform tDCS.

The biggest barrier to widespread tDCS use in the workplace is that it needs at least one highly-trained person to monitor its activity. It is very dangerous to just buy a tDCS kit and apply a current to your scalp without first screening your brain for points of stimulation and having a professional administer stimulation. The solution to this problem is to use computers to help administer tDCS through a brain-computer interface (BCI). BCIs are surgically-implanted electrodes in the brain that convert neural information into digital code that a computer can then interpret and modify. BCIs are beneficial in that they allow for two-way information flow, meaning that neural signals can be sent to a computer, and a computer can send its own signals back directly via neuroprosthetics. These signals could be modified from the original signals sent into the brain, where it will result in neural impulses and human action [24]. The idea is to implant BCIs to transmit neural information to a computer to determine what impulses to modify and where to modify them. These modifications can be sent back through the BCI to a tDCS electrode, which will stimulate different parts of the brain as specified by the computer.

BCI technology for neuroenhancement is still way ahead of our time and much of its components are still under early development. However, companies such as Neuralink are leading the way in BCI research for neuroenhancement and are finding ways to make them safe and accessible to use [25]. Currently, they are working on ultrathin high-bandwidth electrode “threads” connected to a minuscule chip, as well as a similarly-sized robot to precisely implant them deep inside the brain with micron precision. At about 10 micrometers combined, the robot and its thread will be as wide as the outside ridge of a US penny. One chip and its threads will be able to record the activity of over 10,000 neurons in very specific regions of the brain, and Neuralink claims that one person can have 10 chips implanted all at once. Neuralink plans to implement wireless communication in a hearing aid-like BCI device between the brain and a computer, as well as develop a BCI ecosystem accessible via a Neuralink mobile app [25]. Neuralink plans to conduct experiments on human subjects as early as late 2020.

It is very ironic that our path to finding a solution for helping older folks gain ground on an increasingly computerized job environment leads us back to using computers as a solution. In essence, the use of tDCS and BCI technology can be thought of as an amalgamation with our competitors. Because we as humans have lost ground to computers, we will soon incorporate a computer into our own human minds. Like the old saying goes, “if you can’t beat them, join them”.

The More That’s on the Mind, the More There Is to be Conscious Of

Before neuroenhancement can be made widely accessible to seniors, all methods must pass clinical trials on healthy subjects. This process may take years to complete, with some methods never making the cut. Because many neuroenhancing drugs already have approved medical uses for disease treatment, clinical trials on healthy humans may be given priority. However, drugs like modafinil and methylphenidate are known to carry a risk for abuse, and its classification under the Controlled Substances Act may slow down clinical research even further due to stricter regulations on human experimentation. Despite this, researchers are constantly synthesizing, testing, and modifying neuroenhancing drugs in order to capture all of their benefits with minimal risks and side effects.

Transcranial direct current stimulation (tDCS) is currently being tested in healthy human subjects with studies showing great promise. Currently, the biggest drawback to using tDCS is its inability to target very specific brain regions, which is expected as a non-invasive stimulation method. High-definition transcranial direct current stimulation (HD-tDCS) seeks to improve stimulation precision and accuracy by adding more electrodes with more configurable stimulation patterns [26]. Brain-computer interfaces (BCI) are also seeing testing in healthy human subjects. More and more companies are entering the BCI market seeking to improve BCI accessibility and safety, while driving down the costs of manufacturing. Neuralink, one of the leaders in BCI innovation, plans to run experiments for its BCIs on human subjects as early as late 2020 [25].

To many, the thought of hacking our own brain with chemicals and technology is an eerie proposition. Aside from the potential risks associated with neuroenhancement, such as addiction, harmful side effects, and operator error, ethical issues have been raised regarding its widespread use.

The overarching question surrounding neuroenhancement is its reflection on the human condition and self-concept [27]. Libertarian bioethicists argue that advancements in medical technology are opportunities to overcome human limitations and create progress within the human condition. They claim that it is an individual’s responsibility to challenge life’s boundaries and that restricting neuroenhancement infringes on an individual’s natural rights. Conservative bioethicists argue that tinkering with a healthy human brain undermines human nature and is damaging to the self-concept. They claim that neuroenhancement could serve as another factor that can lead to widespread inequality that could uproot our social structure if it is not regulated.

Another issue regarding neuroenhancement is equality and privilege. As a new and emerging science, neuroenhancement will come at a high cost in its early stages of consumer availability [28]. This will mean that it will be most accessible to the wealthy and the most privileged, who would then be able to gain cognitive advantages over everyone else. This disparity in cognitive ability could manifest in income inequality, especially if we consider seniors living on retirement savings. For example, a senior with enough resources to afford neuroenhancement will have an edge in the job market over a senior without the means to afford it.

If neuroenhancement becomes more widespread in the workplace, there is a concern that workplace standards will be raised in response to the increase in productivity seen in neuroenhancement users [28]. This could in turn create pressure in non-users to start using neuroenhancers to keep up with their colleagues. Many may feel coerced into doing something they would not otherwise do or do something that does not coincide with their beliefs. Bioethicist Jacob Appel suggests that employers could go as far as to require their employees to undergo neuroenhancement for their work [27]. Such a measure poses neuroenhancement as a barrier to entry for many if one doesn’t have the means to buy the drugs or undergo the procedures to be a competitive job applicant.

Concerns over hacking, data mining, and cybersecurity have plagued every single digital device we use in our life. With the implementation of BCIs, these concerns are further magnified as our own neurological information can be accessed via computer, leaving it vulnerable to hacking and data mining. Hackers have been able to take control of several different medical devices, including hearing aids, insulin pumps, and even pacemakers. With BCI manufacturers looking to implement wireless communication and internet connectivity in their devices, there is little doubt that BCIs will fall victim to hacking. A hacker could take control of one’s BCI and essentially “read his/her mind” by stealing neurological data. If integrated with other neurological devices, such as tDCS electrodes, a BCI hacker could send unwanted electrical currents to their victim’s brain, which could cause irreversible brain damage or even death. “Big data” has been a buzzword in mainstream media as of late. There is a possibility that hackers could mine neurological data from a person’s brain to sell off to others, allowing anyone to analyze the person’s thought patterns and cognitive activity. The person whose neurological data has been mined could be shown specific advertisements based on their brain activity, for example. With BCIs providing large amounts of information connected to other devices, precautions and security measures must be implemented before they can be rolled out for the public to use.

Overall, these ethical issues come together when considering how neuroenhancement should be regulated in the future. Neuroenhancement does carry the potential to harm oneself and society as a whole. However, as a science, it is important to keep pushing neuroenhancement forward to create new opportunities and improve livelihoods for all individuals. It is unlikely that neuroenhancement, with all of its potential risks, will go entirely unregulated. However, current policies and regulations do not yet ensure that the benefits of neuroenhancement will be maximized and the risks will be minimized. As neuroenhancement becomes more accessible and widespread, policies and regulations must reflect the changes that it will bring.

The Case for Neuroenhancement

In its current state, neuroenhancement is still being developed into an accessible, widespread treatment for seniors to use. Neuroenhancing drugs are constantly being synthesized, tested, and modified to maximize benefits and minimize harm. tDCS trials show great promise and equipment is now being sold to consumers at affordable prices. BCIs are constantly being worked on to become microscopically smaller and more electrode-dense with human trials being run very soon. However, all neuroenhancement methods carry potential societal implications that our world may not yet be prepared for. Neuroenhancement has the potential to widen socioeconomic divides, pose as a barrier to entry to the workforce, and infiltrate our own personal privacy. There is a debate among bioethicists of whether neuroenhancement is a fundamental human right or damaging to the human condition. Bioethicists also question neuroenhancement’s ability to carry more societal benefits than unforeseen consequences. No matter the stance, policies and regulations must be adapted to ensure the safety and stability of the individuals using neuroenhancement and the society around them.

The prospects of neuroenhancement inject a lot of hope for many seniors who are trying to enter or stay in the workforce even as the workforce moves past them. Though many may argue that people at retirement age should stay out of work for health and business reasons, our current socio-economic position does not reflect this. As savings dry up and retirement finances become less stable, seniors are now the fastest-growing segment of our workforce. However, seniors are much less suited for modern jobs that require sharp attention and fluid intelligence. Neuroenhancement provides an opportunity to keep working even as we enter our golden years to ensure financial stability. With more seniors working and becoming financially stable, there will be less reliance on the young to keep supporting the old. This allows for maximum productivity among the two generations. By exploiting the mechanisms that drive our brains’ ability to think, learn, and solve, neuroenhancement could be the answer to those who are seeking to work at an older age. With more time and development, neuroenhancement may be able to revitalize a large part of our workforce and give new opportunities to older workers where they would have been left behind.

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