Most Helpful Customer Reviews
48 of 53 people found the following review helpful:
5.0 out of 5 stars
Brain-Based Values, April 1, 2006
Brain-Based Values
Patricia S. Churchland
Originally appeared in The American Scientist, July 2005.
Envision this scene: Socrates sits in prison, calmly awaiting execution, passing the time in philosophical discussions with students and friends, taking the occasion to inquire into the fundamentals of ethics: Where do moral laws come from? What is the root of moral motivation? What is the relation between power and morality? What is good? What is just?
Ever modest, Socrates confesses ignorance of the answers. The pattern of questioning strongly hints, however, that whatever it is that makes something good or just is rooted in the nature of humans and the society we make, not in the nature of the gods we invent. This does not make moral rules mere conventions, like using a fork or covering one's breasts. There is something about the facts concerning human needs that entails that some laws are better than others.
From the time of Socrates to the present, people have sought to give a natural basis for morals-that is, to understand how a moral statement about what ought to be done can rest on hard facts, albeit facts about conditions for civility and peace in social groups. How can ethical claims be more than mere conventions? How can such claims be rooted in facts about human nature but have the logical force of a command?
Developments in evolutionary biology have helped to explain the appearance of moral motivation in humans and in other eusocial animals-animals that display behavior involving cooperation, sharing, division of labor, reciprocation and deception. In these species, various forms of punishment (shunning, biting, banishing, scolding) are visited on those who threaten the social norms. Ethological studies help us appreciate that, at a basic level, human social behavior has much in common with that of other species.
Developments in neuroscience hold out the promise of extending the naturalistic perspective to aid in the understanding of how the brain and its circuitry underlie the capacity to learn social norms and to behave in accordance with them. Many of us ponder the possibility that discoveries about brain function and organization will challenge the conventional wisdom on which our system of justice relies and will allow us to see more deeply into the biology of social behavior, including moral behavior. In his new book, The Ethical Brain, Michael S. Gazzaniga takes an unflinching look at the interface between neuroscience and ethics, and offers his own thoughtful perspective on some of the tough questions.
As a graduate student at Caltech, Gazzaniga studied under one of the towering figures of neuroscience, Roger Sperry, whose lab pioneered research into the cognitive effects of cutting the fibers connecting the two cerebral hemispheres (a procedure used to treat intractable epilepsy). Ingenious testing of these so-called "split brain" patients revealed that their two brain hemispheres operated independently, each hemisphere acting almost like a distinct person. These were profoundly important results, both for philosophy and for neuroscience. Gazzaniga went on to explore the neurobiology of higher mental functions-attention, memory, choice, consciousness-more generally, always with a philosophical question biting his heels. He currently serves on the President's Council on Bioethics. Thus it is especially fitting that he should now pen his thoughts on neuroethics.
The most fundamental neuroethical issue concerns free will and responsibility. The mind is what the brain does, and the brain is a causal machine. Consequently, deliberations, beliefs, decisions and ensuing behavior are the outcome of causal processes. Typically, the causal processes leading to awareness of a decision are nonconscious. The "user illusion," nevertheless, is that a decision is created independently of neuronal causes, by one's very own "act of will." Some philosophers-usually called libertarians-resolutely believe that voluntary decisions actually are created by the will, free of causal antecedents. Like flat-earthers and creationists, libertarians glorify their scientific naiveté by labeling it transcendental insight.
Gazzaniga, like many a philosopher, realizes that it would make a mockery of the criminal justice system if the accused could escape punishment simply by pleading that the brain is a causal machine and hence he or she lacked free will. So when and how ought we to hold people responsible for their behavior?
Gazzaniga's answer has two components: First, he claims that we hold a person responsible, causality notwithstanding, so long as his or her behavior was unconstrained-so long as the person could have done otherwise. Second, Gazzaniga identifies responsibility as a social, not a neurobiological, property. His point is that our institutions for assigning responsibility derive from the need to maintain and protect civil society, which must figure out suitable criteria for when and how to punish those who violate the rules.
Gazzaniga sums up his solution to the problem of free will by saying that "the brain is determined, but the person is free." The logic of this brain/person duality is not particularly compelling, or even coherent, yet as Gazzaniga's writing implies, it may be in our collective interest to live by this dualistic legal fiction.
The obvious test of the "let's pretend" solution is to see whether it can specify relevant criteria for distinguishing between those who could have done otherwise and those who could not have, and between those cases in which mens rea (literally, a guilty mind) obtains and those in which it does not. (Mens rea is a criminal law concept requiring proof that the mental state of the accused was such that he or she committed the crime purposely, knowingly, recklessly or negligently; strict liability, in which state of mind has no relevance, is fairly rare in criminal law.) Here, however, the wheels fall off Gazzaniga's solution.
Worried that ever-cunning defense attorneys will try to extract more exculpatory mileage out of neuroscience than the facts can support, Gazzaniga magnifies the incompatibility of responsibility as applied to persons and the causality that governs functions of a person's brain. He says, "The issue of responsibility . . . is a social choice. In neuroscientific terms, no person is more or less responsible than any other for actions." This implies that there are no relevant factual differences between someone with, say, obsessive-compulsive disorder and someone who can resist impulses. Can this conclusion be right? As the British neuroscientist Steve Rose has pointed out, badness, just as much as madness, involves the brain.
The flaw in Gazzaniga's argument is that although responsibility is assessed in a social context, the capacity to learn social norms and the capacity to act in accordance with them are matters of individual brain function. It is precisely because an important difference exists between a normal brain and the brain of someone who is seriously demented or unreachably deluded that such people are not considered responsible for crimes they might commit. Moreover, judicial institutions rely on threat of punishment to deter. The late maturation of the prefrontal cortex (with reference to neuronal density, synaptic density, dendritic length and myelination) means that the brains of mature adults are critically different from those of young children-which almost certainly accounts for the child's more modest ability to appreciate the consequences of his or her choices and to resist temptation.
Satisfied that the brain/person duality is workable, Gazzaniga pushes the hypothesis further. He says that because assignment of responsibility is a social matter, not a matter of fact about the brain, neuroscience cannot possibly "settle" whether a person is responsible. Granted, determining legal responsibility is complicated, and neuroscientific knowledge cannot be substituted for knowledge of the law and of community standards. What kicks up sand, however, is the unfortunate choice of the word settle. Neuroscientific evidence can surely be relevant, even if the disposition of the case is settled by members of a jury whose brains follow some form of constraint-satisfaction algorithm. Yet Gazzaniga resolutely insists upon the stronger point: Neuroscientific data are not even relevant.
Why not? His reasoning goes like this: As a group, schizophrenics, for example, are no more prone to violence than individuals in the general population. Ditto, he says, for people with prefrontal lesions. If a given schizophrenic, Mr. Jones, kills someone, it is mere theater to display his brain scans in court, picking out some abnormality or other as "the cause" of his homicidal behavior. There are no relevant differences that neuroscience knows about that can explain why Jones killed, but Smith (also schizophrenic) did not. Not everyone with low glucose levels engages in violence; not all citizens raised in an inner-city hell become drug dealers; not all premenstrual women beat their children. We can assume there are differences in the brain, but whatever these differences happen to be, they are not, he believes, relevant to determination of responsibility. Why? Because there is no "responsibility" area whose functionality can be examined through a scanner or with electrodes-not now, not ever. Responsibility is a social construct, not a brain function. This point, he believes, holds generally-for schizophrenics, for patients with prefrontal cortex lesions, and so forth. And for good measure, he suggests that the insanity defense itself is too imprecise and problematic to be of practical value.
It is widely expected that...
Read more ›
Help other customers find the most helpful reviews
Was this review helpful to you? Yes
No
23 of 25 people found the following review helpful:
2.0 out of 5 stars
A nice literature review at best, and nothing more, June 23, 2009
This review is from: The Ethical Brain: The Science of Our Moral Dilemmas (P.S.) (Paperback)
Michael Gazzaniga is one of the most renowned neuroscientists of our time, and rightfully so; his experiments regarding the role of the corpus callosum in connecting left- and right-brain functions really changed the way that we understand the brain. It should come as little surprise, then, that he was eventually rewarded with a seat on the President's Council on Bioethics.
It should also warn potential readers of the fact that a good neuroscientist does not make a very good ethicist -- or indeed, much of an ethicist at all. Each chapter of this book (except the last, about which more below) basically has the same format: there is a well-written survey of the developments in brain science that implicate a particular ethical issue, and then a couple of pages of Gazzaniga's "Perspectives."
But these Perspectives shed virtually no light on any of the issues. If anything, they show how little science can tell us about them. In the essay on "My Brain Made Me Do It," Gazzaniga canvasses the literature on what we can know about mental states from the neuroscience, and then concludes that mental state or guilt for legal purposes is not a scientific question because scientists investigate brains, not minds. True enough; and something that anyone with the most cursory knowledge of the field could have told him beforehand.
Often he just seems to make assumptions about things without making it clear. He favors drugs that enhance our intelligence or cognitive capabilities because you can't stop them and in any event, most people won't use them. But he is outraged at athletes using performance-altering drugs because in some sense that violates the "social contract" that we all accept. The obvious question is why using intelligence-enhancing drugs would not also violate the social contact is completely lost on him. Maybe wealthy families will be able to afford these drugs to do better on the SAT, and thus create a more plutocratic base for college admissions (a problem that's bad enough already). Why isn't that a violation of the social contract? What does he mean by a social contract, anyway? Gazzaniga cannot answer this question because he never asks it.
I was really looking forward to the final chapter, in which Gazzaniga claims to set forth a theory of universal ethics not bound by time or culture. A fascinating and crucial topic -- and one that deserves a whole lot more than he gives it, especially because his evidentiary base is essentially one short journal article, and a quarter-century old book by James Q. Wilson (who is neither a scientist nor an ethicist). There is an awful lot of work that has been done on comparative responses to ethical dilemmas, ways in which cultures differ and don't differ, etc. Gazzaniga never mentions them.
The chief value of this book -- indeed, the ONLY value of this book -- is the review of the neuroscience findings. That is genuinely helpful to someone like me who is not a scientist. But I admit that I began to worry after the last chapter, where I have read a little (just a little) on the issues surrounding the universality of ethics, and found that Gazzaniga didn't seem to be aware of them. Uh oh.
Maybe I'm being too harsh. But that's because I was really looking forward to reading this book. Gazzaniga is a great neuroscientist, and thought he would have something interesting and provocative to say. He just doesn't.
Help other customers find the most helpful reviews
Was this review helpful to you? Yes
No
18 of 20 people found the following review helpful:
4.0 out of 5 stars
The Brain's Moral Code, August 22, 2006
What can the study of the brain tell us about how we should live our lives? Quite a lot, argues Michael Gazzaniga in his new book The Ethical Brain. Gazzaniga is a professor of cognitive neuroscience (the study of the relationship between brain and behavior) at Dartmouth College and a highly respected researcher in his field. Thus, he was an obvious choice for inclusion in the President's Council on Bioethics, on which he has served since 2001. As a member of that council, he has witnessed "how the fear of science can stifle rather than further research" (pp. xv-xvi). In response, Gazzaniga argues for neuroethics, which he defines as "the philosophy of living informed by our understanding of underlying brain mechanisms" (p. xv, italics in original). Gazzaniga's bottom line, in most cases, is that we should allow science to advance without trepidation, trusting to an innate sense of morality that will guide us sensibly through the ethical issues raised by scientific advancements.
Beginning and end of life issues are at the forefront of current bioethical discussion. Defining the beginning of human life impinges on the important issues of abortion and stem-cell research. Under the traditional religious view that human life begins at conception, abortion is rightly viewed as equivalent to murder, and stem-cell research, which depends on the tissues of aborted fetuses, is morally reprehensible. Those who argue for reproductive freedom need to delay the conferral of humanity to the embryo if they want to maintain that abortion is not morally wrong, but there is no clear milestone during development where an obvious shift from non-humanity to humanity occurs. Likewise, the potential medical benefits from stem-cell research need to be weighed against the morality of terminating the life of a potential human being; deciding that an embryo is not human until some stage after which the researcher is no longer interested in the embryonic tissue tips the balance in favor of pursuing the research.
Gazzaniga proposes that the way we define the end of human life can inform us on our decision about when human life begins. Brain death is now generally accepted as the definition of the end of human life, even if the exact criteria for determining brain death have not been completely decided. Thus, if the brain is no longer able ever again to produce conscious awareness, human life has ended even though basic bodily functions can still be maintained. If the cessation of sentience marks the end of human life, argues Gazzaniga, then the initiation of sentience should mark the beginning of human life. A necessary condition for consciousness is the existence of a nervous system, which starts developing in the human embryo by the sixth week. However, this nervous system must be sufficiently complex for the fetus to respond to environmental stimuli (an important benchmark of awareness), and this does not occur until around week 23, when the fetus is also capable of surviving outside of the womb. This is also the age at which the fetus gains legal protection from abortion.
Clearly, this argument will not convince those who believe the embryo is endowed with a soul at the moment of conception, but again science creates problems for religion. The first couple of weeks after conception are critical. One reason is that some 60 to 80 percent of all naturally conceived embryos are spontaneously aborted during this time period, generally without the mother's knowledge. Another reason is that twinning generally occurs during this time frame, and in addition it is also possible for twin embryos to recombine into a single embryo during this period. These observations raise important theological issues, seriously weakening the argument that human life begins with an ensoulment at conception.
Toward the end of life, the gradual loss of cognitive functioning through dementia also muddies the boundary between sentience and non-sentience. In recent years, though, new drugs and therapies have been developed to combat dementia. These memory enhancers can provide benefits as well to those within the normal range of cognitive functioning, leveling the playing field and making geniuses of us all. At least, this is the brave new world that Gazzaniga imagines. However, what he does not consider is the possibility that memory-enhancing drugs could set off a mental arms race in which the normal distribution of intelligence is simply shifted upwards, not narrowed.
Gazzaniga discusses three areas where neuroscience can inform criminal justice: the concept of free will, the use of brain imaging devices as lie detectors, and the fallibility of memory and eyewitness testimony. First, Gazzaniga holds the view, common among psychologists, that free will is an illusion; however, he notes that conscious awareness can lead to the inhibition of socially undesirable behaviors, an ability he refers to as a "free won't" (p. 93). Damage to the frontal lobe of the brain, though, can lead to a loss of inhibition of socially unacceptable behaviors, and so the criminal justice system needs to take into account the condition of the brain in determining culpability. Second, Gazzaniga discusses the use of Computerized Knowledge Assessment (CKA), which uses EEG measurements to determine an individual's familiarity with the details of a particular criminal act or terrorist group. Gazzaniga rightly criticizes CKA for going "far beyond what neuroscience knows" (p. 114) and contends that CKA is not likely to ever be any more reliable than polygraph tests. Even more disconcerting, however, is the report that the "CIA is now using this technique, though we do not know to what extent" (p. 111). Finally, Gazzaniga makes a strong case for the unreliability of eyewitness testimony in criminal proceedings. Drawing on his own work in this area as well as that of Elizabeth Loftus and Daniel Schachter, Gazzaniga convincingly demonstrates that memory is highly unreliable and easily modified. This section of the book was by far the best supported, and we can be encouraged by the fact that the criminal justice system is starting to take note of the findings of neuroscience, although it will probably still be a very long time before it completely sheds its outmoded views on human consciousness and memory.
In the final section of the book, Gazzaniga discusses the emerging field of neurotheology, which investigates the role of the brain in religious experience. Three areas of the brain have been identified as playing a role in religious and ecstatic experiences. First, the frontal lobe is found to be active during meditation; however, since the frontal lobe is generally involved in attentional processes, this finding is not surprising. Second, epileptic seizures in the temporal lobe can lead to profound religious and ecstatic sensations. Temporal lobe epileptics do not exhibit the convulsions and loss of consciousness typical of grand mal epilepsy, although they may appear to space out for the duration of the seizure. After the seizure, however, temporal lobe epileptics may report a profound experience, a feeling of oneness with the universe, or communication with a divine entity. Third, it has been found that electrical stimulation of an area of the brain called the right angular gyrus (above and behind the right ear) induces out-of-body and other-worldly experiences. Thus, key experiences of devotional religion are associated with specific brain activity.
Gazzaniga tries to link this discussion of the physiology of religious experience to his assertion that humans possess an innate moral-ethical system that will guide them wisely through the moral issues presented in this book. However, religion is not the same as morality, despite what the Religious Right would have us think, and the brain structures that support religious experience are not necessarily the brain structures that would support an innate moral code. Gazzaniga tries to support his claim by noting that people respond similarly to moral dilemmas across cultures, and furthermore that people have great difficulty articulating their moral choices. Research in evolutionary psychology suggests that certain types of moral reasoning (inclusive fitness, reciprocal altruism) may in fact be hard-wired; however, this type of moral reasoning may not be sufficient for dealing with ethical issues in the twenty-first century.
Throughout The Ethical Brain, Gazzaniga argues that we should rely on our innate moral-ethical system to guide us through the ethical problems raised by advances in science. Gazzaniga seems to find little need to dwell on the ethical implications of stem-cell research and memory enhancers because he trusts humans to work things out for the best in the end. On the other hand, though, he finds the use of brain-imaging technology to infer mental states to be unethical and dangerous. However, Gazzaniga never explains why we should trust our innate moral codes in some cases but not in others. Unfortunately, The Ethical Brain fails to live up to its promise of showing how recent findings in brain science can inform the ethical choices we need make at the cutting edge of science.
Help other customers find the most helpful reviews
Was this review helpful to you? Yes
No
|
|
Most Recent Customer Reviews
|
