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Perspectives
Neuroethics: New Science, Old Hubris By Kevin Finneran
Advances in neuroscience are generating speculation about a completely new understanding of human consciousness, abilities, interests, values, and ethics. Although the research developments are exciting and potentially useful in dealing with some psychological ailments, we should be wary of those promising a fundamentally new model of human nature. A look back at an earlier “window into the human mind” should introduce a healthy dose of skepticism.
Phrenology In the late 19th and early 20th century there were many people, among them Ralph Waldo Emerson, who believed that one could discern a great deal about an individual’s character, talents, and interests from studying the bumps on his head. The theory was that the bumps in the skull corresponded with the physical structure of the brain and thus to these various personal characteristics. There are still some believers today. If you go to www.phrenology.org, you can discover how much the science has advanced.
For everyone other than these few believers,
phrenology is a pseudoscience that has become a joke. On an episode of
The Simpsons, Mr. Burns subscribes to the practice of “retrophrenology,”
by which one alters a person’s psyche by adding bumps to his head in
prescribed places. Although phrenology itself is easily dismissed, the principles underlying the practice will sound familiar to anyone paying attention to contemporary neuroscience. In The Anatomy and Physiology of the Nervous System in General, and of the Brain in Particular, Franz Joseph Gall, the founder of phrenology, summarizes the fundamental assumptions that formed the foundation for the practice of phrenology that he developed:
Although contemporary neuroscientists would obviously disagree with some of the specifics, many would concur that the physical and chemical structure of the brain can explain the human psyche—interests, abilities, personality, character, and ethical choices. They are working at breaking down the barrier between the physical brain and the metaphysical concept of the mind, evicting what Arthur Koestler called the “ghost in the machine.”
Phrenologists used one enlightening medical study as the empirical foundation for their theory. In 1848, Phineas Gage, a Vermont railroad worker clearing the path for new tracks, was placing a dynamite charge when it accidentally exploded, sending a 3-foot metal bar through his chin and out the top of his head, severely injuring part of his brain. He recovered from the accident, but was in everyone’s opinion a different person afterward. Formerly a cheerful and agreeable person who was industrious and well liked, he became an irritable, foul-mouthed, unmanageable pain in the ass. In the eyes of his coworkers, he had become a completely different person. The phrenologists trumpeted this incident as clear evidence that a change to the physical brain resulted in changes in personality and character, which were supposed to be aspects of the nonphysical mind.
Although Gage’s case is important, it is not evidence for the reliability of phrenology. Indeed, phrenology produced no testable hypotheses, making it fertile ground for charlatans. The operation of the brain, the nature of consciousness, the ways people make decisions are all still largely hidden from human understanding. The problem for the phrenologists was that they could not see inside the brain; the closest they could get was the skull.
Neuroscience Today’s neuroscientists have a vast array of new tools that offer a window (of uncertain clarity) into the skull. Positron emission tomography, functional magnetic resonance imaging, electroencephalography-derived methods of event-related potentials, magnetoencephalography, and near infrared spectroscopy enable scientists to observe brain activity in real time as a patient laughs, cowers, puzzles, or attacks. We can see how various emotions, perceptions, or activities correspond to observable chemical and electrical activity in areas of the brain.
We now have mountains of evidence that link parts of the brain with specific human abilities and behaviors. We have seen how brain injuries can have very specific effects, such as damage to short-term memory or the sudden inability to speak a language that one can still understand. With the advent of psychoactive drugs, we have seen how a change to the chemistry of the brain can eliminate severe schizophrenia or depression. Indeed, it is now commonplace to find doctors prescribing Ritalin or Adderall for children with attention deficit hyperactivity disorder, and to find young people using these drugs for recreational or other purposes. Prozac and other serotonin reuptake inhibitors have become extremely popular with adults who are prone to depression. Modafinil, which is prescribed to promote wakefulness in those with sleep disorders, is attracting interested from healthy Type A’s who think it will help them work longer and harder. Researchers looking for drugs to treat people with dementia and other memory problems could find that they have a product that is very popular with students. Fans of the film The Eternal Sunshine of the Spotless Mind will be intrigued to know that researchers are pursuing a drug that will prevent the formation of unwanted memories in those who experience traumatic events.
Scientists see enormous opportunities in this research. They imagine physical procedures that will cure mental illness, eliminate criminal inclinations, expand human capabilities, and ultimately raise the level of human satisfaction and happiness. We’re a long way from achieving those goals, but that hasn’t stopped people from speculating about what it will mean if we do gain this knowledge of the brain.
A few observers believe that it will force us to develop a new conception of free will and personal responsibility. For the first time it may be possible to breach the privacy of the human mind, to judge people not only by their actions but also by their thoughts and predilections. Scientists and ethicists have already begun to sketch out the problems we will have to face. Martha J. Farah of the Center for Cognitive Neuroscience at the University of Pennsylvania listed many potential ethical problems in an article in the January 2005 issue of Trends in Cognitive Sciences, January 2005.
Some of these are similar to choices we have already confronted. For example, advance in neuroscience open the possibility of brain enhancement, the equivalent of steroids for IQ or Erythropoietin for concentration. The problems that arise are similar: Does enhancement give some people an unfair advantage? Are there side effects? What if only the rich can afford them? Will everyone feel pressure to use them? What if the military decides they are necessary to improve the quality of all troops?
Similarly, there will be people who want to engage in “brainotyping,” just as many people now favor genotyping. The stated goal will be to identify innate abilities or tendencies, to pick future rocket scientists and child molestors. The obvious problem is that we do not know nearly enough to make pronouncements based on biology as destiny. Brains, like genes, interact with their environment. Although one might be able to create a retrospective scenario to explain how an individual arrived at a certain state or decision, making a reliable prediction is impossible.
What is new, ambitious, and troubling is the notion that we can reach deep enough into the brain to arrive at the essence of ethical decisions. The implications are profound. Taken to its logical end, this approach would be able to explain all ethical decisions in terms of physical processes in the brain. If an individual cannot choose the brain she is born with and the functioning of that brain is determined by its original structure and the physical changes that occur in response to events and experiences beyond the individual’s control, is the individual capable of making an independent ethical choice? Or do we have a new excuse for our ethical lapses? My brain made me do it.
We already have a number of qualifiers for ethical and legal responsibility. We don’t expect preschool children to be responsible for the morality of their actions, and we treat young teens separately in the criminal justice system. Likewise, people with extremely limited intelligence or severe mental illness are held to different legal and ethical standards because we believe that they lack the ability to make conscious, deliberate, and informed decisions.
If one believes that progress in neuroscience will eventually unlock all the secrets of the brain’s operation, it becomes possible to imagine a world in which all human behavior can be explained by physical processes. What becomes of ethical choice and responsibility in such a world? And if our ability to intervene in the brain’s functioning through drugs and surgery keeps pace, will it then be possible to design brains that will always adhere to society’s rules. Although this might at first seem to be a perfect solution to the problems of unethical and criminal behavior, it introduces the more fundamental question of what is ethical.
Legal and ethical norms are the result of a long, messy history of social and cultural evolution. With the growth of democracy, these norms reflect the input of ever larger numbers of people and incorporate the wisdom of crowds. Those who historically have been without power—slaves, women, ethnic minorities—have gradually been able to force change in those norms that served to meet only the needs and desires of the powerful. But what happens in a world in which decisions result from brain chemistry? There is no shared sense of right and wrong, only the result of physical brain function. And whose brain function will determine what is the norm? Will it be Mr. Burns? The potential for those in power to impose their personal norms on the society becomes unlimited. Add to that the potential to “inject” the desired behavior into those whose brains lead them to behave in inconvenient ways, and Brave New World begins to look miraculously insightful.
Although one might take some solace in the fact that neuroscience is nowhere close to deciphering the intricacies of the human psyche, that would be a fool’s peace. From phrenology to eugenics to any number of other attempts to use pseudoscience to promote authoritarian schemes, charlatans and other opportunists have eagerly rushed ahead of what is known to act on what they believe. In fact, it’s easier to believe what one wants before knowledge intervenes to limit a twisted imagination. The megalomaniacs with wild-eyed plans to improve or perfect the human species need to be met with vigilance and skepticism. A little knowledge and a lot of hubris combine to create the conditions that Yeats described so hauntingly:
The best lack all conviction, while the worst
Kevin Finneran is the Editor-in-Chief of the journal Issues in Science & Technology.
The views expressed here are those of the author. |
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