Neuroscience research has advanced over the last few decades at an unprecedented pace: the U.S. government even declared the 1990s to be the “Decade of the Brain,” a shout-out to the phenomenal efforts of neuroscience researchers during that time [1]. But the surge in novel medicines and therapies affecting the brain sparked the need for a conversation about the ethical ramifications of obtaining information about, from, and for the good of our thinking organ. Most conversations and decisions set in place by ethicists regarding medicine and biomedical research occur through the study of bioethics; however, neuroscience covers so much brand new, uncharted territory that in 2002, it gained its own moniker for philosophical conversation: neuroethics [2].

Neuroethics, as a study, encapsulates both the ethical and philosophical sides of conducting science and practicing medicine that relates to the brain. Where bioethicists closely consider how certain technologies can affect individuals and society, neuroethicists additionally study the physiological mechanisms behind morality and ethics in the brain. While this review focuses on the former over the latter, it is important to recognize that our understanding of the ways in which the brain allows humans to comprehend the notion of right and wrong is crucial for neuroethics research. As modern medicine searches for medical solutions for disorders affecting individuals’ behavior and personalities, researchers need to fully understand the physiological mechanisms behind both neural disorders and behind the cognitive processes affected by the disorders. The following three examples outlined in this review—neuroprosthetics, neuromarketing, and neural enhancement—provide an interesting look into some of the larger bioethical issues concerning our research of the brain.

Technology and Society

A crucial aspect of neuroethics involves the study of how neural technologies affect the people and societies they are created to benefit. Though the process for the approval of new devices by the FDA is thorough, new technologies and drugs have the potential to affect people in ways other than those intended by physicians and scientists. This has been especially true regarding advances in neuroprosthetics, or technologies that help restore impaired neural function. Just as a prosthetic leg is designed to help an amputee walk or balance, neuroprostheses help people regain function of brain regions or nerves after they have been damaged. These include technologies such as cochlear implants, which are at the center of some of the widespread ethical concerns regarding invasive biomedical technologies. Cochlear implants compress, relay, and transmit auditory signals into the cochlear nerve, providing deaf patients with a measure of sound cognition that is otherwise unobtainable [3]. While cochlear implants are sometimes regarded as the “most successful neuroprostheses in clinical use”, the use and research of the implants has garnered a great deal of backlash from the Deaf community [3][4]. While deafness as a condition is typically regarded as a disability by the medical community and the greater public, the Deaf community has long held that losing the ability to hear simply allows one to be a greater participant in Deaf culture rather than be excluded from the culture of the hearing world. The ethical discussion involves respect and recognition to- wards Deaf culture. Many bioethicists, such as Robert Sparrow, argue that by allocating large amounts of money for research on cochlear implants—research thought to “cure” deafness—institutions are actively disrupting Deaf culture in a way that would not be tolerated if the culture didn’t stem from the existence of a “disability” [4]. Sparrow explains that the amount of money and research allocated to technologies such as cochlear implants disrespects Deaf culture so significantly that ethicists have begun to discuss whether or not the development of more effective aural prosthetics should be allowed altogether [4]. The cochlear implant is a very unique example in that the community it affects is relatively large compared to many other groups using neuroprosthetic technologies. While not many other communities relate to the situation in which the Deaf community finds itself, ethical considerations are still necessary when researching technologies that aim to “cure” conditions that blur the line between normal and impaired. Not all conditions that affect the brain are debilitating enough to inhibit people from participating in or experiencing the world around them. If biomedical technology gives physicians the power to treat any condition that makes a brain “different” from the majority, we need to sincerely consider whether these technologies positively help individuals and society, or harmfully “normalize” the community around us.

Another problem surrounding neural prosthetic research lies in the physical connection between the technology and the patient, rather than between the patient and society. Some recently developed technologies use surgically implanted electrodes to directly target neural pathways with chemicals and electrical signals in applications such as brain-computer interfacing and neural function restoration [5][6]7]. And while the results from some of the prosthetics have been out- standing, several problems remain after the technology has been in the body for a long period of time [6]. A certain amount of upkeep and care is required for many of these tools, and often the only source of maintenance comes from small research companies; there are no repair shops for neuroprosthetics. If a company researching a technology cannot secure funding to maintain clinical trials, then they may abandon the projects no matter how effective they were in treating a certain condition. This scenario happened in 2001 with a company called NeuroControl and their wire implant that sent electrical signals through the body to allow hand movements in patients with paralysis [8]. Unfortunately, funding for conditions that affect less than 200,000 individuals in a population, so-called orphan diseases, can be very difficult to find. NeuroControl went out of business just as their technology was flourishing, leaving many US citizens with surgically implanted wires lying dormant in their bodies with no possibility for maintenance or removal [8].

Biotechnology has the potential to help millions of people, but we need to study and manufacture devices in a way that prevents companies from dissolving and leaving their users without support. Despite efforts by the government to incentivize research into technologies for orphan diseases, examples like NeuroControl show how it is still possible for companies to fold due to financial problems just as they are lifting off the ground [8][9][10][11]. It is essential that lawmakers continue to create measures of accountability for companies involved in both funding and developing neural technologies that are similar to the ways in which physicians and researchers are held accountable for their actions regarding patients.

Neuromarketing: Using Medical Tools Outside of Medicine

Regulations for use of technologies outside of the medical world are equally important to regulating tools within medicine. Medical technology designed for clinical use can find alternative uses across non-medical fields. An example of this lies in the new field of neuromarketing. Coined by an up-and-coming marketing company, the term neuromarketing refers to two practices: the study of how the brain reacts to different consumer-related stimuli, and the accumulation of neural data for direct marketing purposes [12][13][14]. While businesses have practiced using subconscious thought to influence our consumption over the last century—it’s no coincidence that burger joints smell so strongly of freshly grilled burger from a mile away—new neuroimaging tools could take the manipulation of our unconscious to a whole new level. Technologies such as biosensors that have the ability to record and transmit information from physiological systems, such as the brain, are currently making groundbreaking strides for diagnostic data collection [15]. As the ability to correlate our neural signals to our behavior reaches new heights, we may soon have extremely precise tools to easily track the intricate array of cellular interactions in our brains, thus allowing for more accurate predictions of behavior that could be used in marketing schemes [5]. Existing studies already use neuroimaging tools to study correlations between brain activity and purchasing behavior, but it is problematic if this technology is used to market items to individuals without their consent [16]. The intent is rarely malicious, even if driven by a motivation to increase financial gain, but using neuroimaging to track brain activity without informed consent is a significant issue. Personal thoughts, feelings and even motivations that are normally guarded by the firewall of the mind could be significantly compromised if companies gain access to them. Another concern regarding neuromarketing ethics is that neuroscience research conducted for strictly non-medical purposes may not receive the same thorough measures of regulation, such as peer review, that assure medical research is being conducted in an ethical manner. [17]. A century of precedent and overhead regulation has set strong moral and ethical boundaries for medical practices, but how can we ensure that the intentions of marketing companies adhere to the same principles of beneficence, non-ma- leficence, justice, and respect for autonomy that are expected from physicians using the same technologies?

When Therapy Meets Enhancement

One other important idea to consider regarding neuroethics involves the conversion of technologies created as a means of therapy into a means of enhancement. The demarcation between the two ways of using a technology usually applies to situations where a technology is used for purposes that are either non-medical, or on people who are not affected by the condition the technology is designed to help. Neuroethicists tend to cite two central lines of reasoning for discouraging enhancement in this fashion: safety of the individual using the technologies, and avoidance of disparities in technology availability between members of differing socio-economic backgrounds [18]. In addressing the first tenant, it is important to note that not all technologies and drugs are free of side effects; physicians regulate the distribution of prescribed drugs and technology use to ensure they are not abused in a fashion that could lead to injuries. And when considering whether to prescribe drugs, doctors are able to properly inform patients of these side effects and make decisions regarding whether or not a patient’s medical history might contribute to negative effects from certain drugs. But beyond safety, ethicists worry that future technologies that have the ability to “enhance” certain traits, especially those such as intelligence, may be unfairly used by groups who have easier access to the tools due to pre-existing wealth disparities between populations. This concern, often classified under the term “distributive justice,” needs to be taken into consideration when engineering new medical technologies. Equality in the distribution of technology is extremely important in order to avoid further socio-economic disparity [19][20]. Sadly, this problem already exists in medicine—individuals with more money have much better access to medicine than individuals in poorer populations. One example of a drug that was intended as a therapy but is often abused for cognitive enhancement is Ritalin. This stimulant, most often abused by individuals who can afford to purchase it, is prescribed by doctors to patients with attention deficit hyperactivity disorder. However, the drug can also instill the same attention focusing enhancements on those without the disorder [19]. Lawmakers and physicians hold an extremely important responsibility to help ensure that drugs and technologies are not abused or misused as the field of neuroscience continues to grow.


The field of neuroethics considers the ethical implications of studying neurocognitive mechanisms and the application of this research in the biomedical field [20]. Neuroethics differentiates itself from other fields surrounding the moral principles of medicine and medical research in that it studies the tools that affect the organ most personal to us: our brains. In studying these topics, neuroethicists must also consider deep questions about the brain and our minds; if we are to begin studying tools that may have an impact on concepts such as “free will” in the brain, we need to first make philosophical judgments regarding what constitutes free will in the first place [21]. Tools, such as those used in deep brain stimulation, that can track or alter signals in our brains related to memory and emotion (two processes intrinsic to our personalities), have the potential to be very dangerous, raising concerns that become more relevant as new advances give researchers and physicians an unprecedented view of our neural pathways [22][23][24].

Neuroethics is a highly interdisciplinary field that con- siders problems from many different angles, from law and philosophy to medicine and society. As this field grows, scientists and ethicists are continuously working to create a better method of determining the “proper” way to use the tools we create in the medical world. Neuroethics is incredibly important to keep neuroscience research progressing in an ethical direction. Because neuroscientific developments are able to impact individuals and societies on a much more personal level than many other medical technologies, it is extremely important for ethicists, scientists, and physicians alike to study the potential impact of these technologies on our world before anything is created that might be abused. The study of neuroethics is connected to philosophy in a very unique way: if we are going to have the ability to alter our humanity, we need to evaluate what exactly it means to be human. Questions surrounding topics such as free will and the nature of knowledge in humans are becoming increasingly important as scientists develop technology that has the potential to quantify our intentions [21]. Society should sleep soundly, however, knowing that a whole new field of study has been created over the past decade to solve problems, such as those presented in this review, before they ever manifest in the first place.


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