WHEN society looks to scientists for answers to ethical questions, how should they respond? As neuroscience in particular sheds more light on what makes us human, it is confronted with some of the most challenging problems that society faces. Will advances in the field change our ideas about morality, responsibility and the law? Should they?
In some areas, new findings can help tackle these issues – the ethical dilemma of when an embryo has the moral status of a human being, for example. But in others, neuroscientists are being asked to weigh in when in fact they shouldn’t. Neuroscience has nothing to say about concepts such as free will and personal responsibility, and it probably has nothing to say about the origins of anti-social thoughts. So dragging it into the courtrooms is dangerous.
Cognitive neuroscience will improve our understanding of these difficult issues, for instance by discovering whether there exist universal morals possessed by all members of our species. The developing field of neuroethics will deal with the social issues of disease, normality, mortality, lifestyle, and the philosophy of living, informed by our understanding of underlying brain mechanisms. It places personal responsibility in the broadest social context. It is – or should be – an effort to come up with a brain-based philosophy of life.
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Consider the questions of when to confer moral status to an embryo, and of when life begins. These are separate. The distinction between them is important.
Biological life begins at the moment of conception. But when does human life begin? The answer has important implications for debates on abortion, in-vitro fertilisation and cloning for stem cell research. Many neuroscientists and some bioethicists believe that human life begins when the brain starts functioning. Consciousness is the critical function needed to determine humanness, because it is a quality that, in its fullness and with all its implications for self-identity, personal narrative and other mental constructs, is uniquely human. An embryo cannot have consciousness until the point in development when it has a brain able to support consciousness. But, as with many ethical issues involving the brain, the answer is not so black and white. Our grey matter creates many grey areas.
The context of the question is everything. One relevant context is biomedical cloning for stem cell research. Neuroscience clearly shows that the fertilised egg does not begin the processes that eventually generate a nervous system until day 14. For this reason, among others, stem cell researchers use fertilised embryos only up until day 14.
But we have to jump all the way to the 23rd week of development before the fetus can survive outside the womb – and then only with advanced medical technology to help it. One could argue that the embryo is not a human being, or deserving of the moral status of a human being, until then. And indeed this is when the US Supreme Court has ruled that the fetus has the rights of a human being.
In making this ruling, the court had to navigate several arguments. One is the “continuity argument” that claims life begins at conception. Its adherents view a fertilised egg as the point at which life begins, and hold that it should be granted the same rights as a human being. They take no consideration of developmental stages. And there is no rational arguing with those who see it this way.
“Biological life begins at conception, but when does human life begin?”
Similarly, the “potentiality argument” views the potential to develop into a human being as conferring the status of a human being. This is akin to saying that a home improvement warehouse is the same thing as 100 houses, since it holds that potential. Neither of these makes any sense to neuroscience. How can a biological entity that has no nervous system be a moral agent?
A further argument, which most often comes into play around stem cell research, holds that the intention of those who create an embryo is significant. Such research may use embryos left unused from IVF processes, where the intention of creating several embryos is to create one or two that are viable for implantation. In natural sexual fertilisation up to 80 per cent of embryos spontaneously abort: thus IVF is simply a high-tech version of what happens naturally. Alternatively, researchers may use embryos created specifically for stem cell harvesting, and here there is never any intention to create a human being.
Looking at the facts, I see that a specific human life begins at conception. A 14-day-old embryo, a clump of cells, created for research, has no moral status. And yet there is something about the look of an ultrasound image of a 9-week fetus that makes me as a father have a personal reaction – it has started to look like one of us.
Is this gut reaction an indication of built-in moral instincts that our brains seek to make sense of with these various arguments? Cognitive neuroscientific research seems to point towards this.
The single most important insight that the cognitive neurosciences can offer ethicists is in understanding how the brain forms beliefs. A powerful example of its drive to do so comes from observing “split brain” patients. These people have had their corpus callosum, the connection between the two halves of their brain, severed as treatment for epilepsy.
Years of testing such people has revealed a brain mechanism, which I call “the interpreter”, that resides in the verbal brain (usually the left hemisphere). This crafts stories or beliefs to interpret actions. If we present the word “walk” only to the right hemisphere of split-brain patients, they will get up and start walking. When we ask them why they do this, their left hemisphere, which is unaware of the command, creates a response such as “I wanted to go get a soda”. Similar findings abound in split-brain research and in studies of neurological disorders.
Another exciting and relevant area of research is Giacomo Rizzolatti’s work with mirror neurons. These indicate a built-in mechanism for “mind reading”, or for empathy. When a monkey reaches for something, a particular neuron responsible for the movement fires in its brain. That same neuron fires in a monkey that is watching the action but not moving. It may be that when we see someone do something, the equivalent neurons are triggered in our brains, creating the same feeling or response in us.
“Neuroscience simply does not say as much as lawyers would hope about personal responsibility”
These contributions from neuroscientists add to our general understanding of brains, minds and even ethics. The area where our counsel is most often sought, however, is the court of law. Lawyers and investigators are excited by the possibility of putting someone in a scanner to see whether they are lying, or whether they have a biological propensity to violence. Couldn’t this information be used to prosecute or defend someone?
The answer should be an emphatic no. While the advances in neuroimaging are exciting, they do not produce that kind of answer. For example, we can show someone pictures of terrorist training camps and watch an area of the brain light up. This may reveal fascinating things about how certain cognitive states work. But it is dangerous and simply wrong to use such data as irrefutable evidence about such cognitive states – let alone the history that led to them, which may include photographs of camps seen in a newspaper.
What we know about brain function and brain responses is not always interpretable in a single way and therefore should not be used as infallible evidence the way DNA evidence is. This is illustrated by responses to Elizabeth Phelps’s use of functional magnetic resonance imaging (fMRI) to examine black and white undergraduates’ responses to pictures of known and unknown black and white faces. She found that the amygdala, an area of the brain associated with emotion, lights up in white undergraduates when they are shown pictures of unknown black faces, but not famous black faces such as Martin Luther King Jr, Michael Jordan or Will Smith.
Some have suggested that this shows that the white students are afraid of unfamiliar black faces. But this is a dangerous and, more importantly, inaccurate leap to make. The finding does not mean that racism is built into the brain.
The tricky thing is that the brain allows us – indeed it is bound and determined – to concoct stories and theories about sets of circumstances or data, and that includes data from experiments on brains. But the resulting stories are not always incontrovertible. There are other explanations for those fMRI scans of students’ brains.
One crucial area where the law and neuroscience should be kept apart is the “my brain made me do it” defence in court. The whole area of research raises the question: if the brain determines the mind and determines our actions, independent of our knowing about it until after the fact, then what becomes of free will?
But personal responsibility arises out of interacting with many human beings. When people come together in groups, laws emerge from their interaction that are not to be found in assessing their brains. You could compare these to the traffic dynamics and rules generated when cars start to interact, producing laws of cooperation that exist not in the cars but in the interactions.
We are still guided by social rules of behaviour, and choose to react and act according to those, in addition to any determined brain mechanisms we may all have. Free will is alive and well. “My brain made me do it” is not an excuse and should not be used in the courts. Neuroscience simply does not have as much to say as lawyers would think or hope about personal responsibility.
Belief formation is one of the most important areas in which cognitive neuroscience needs to teach something to ethicists and to the world. The brain forms beliefs based on contextual information, and those beliefs are hard to change. If you know that, it is hard to accept the wars that rage and lives that are lost due to differences between belief systems. At another level, however, it should come as no surprise that people are behaving as they do: we are wired to form beliefs and to form theories.
In this view, religious beliefs are meta-narratives, rationales we provide for our actions. Common moral reasoning may be built in to humanity, but the stories that attempt to explain and to answer “why” questions about its results are social constructs. If we could come to understand and accept that the true sources of different belief systems are socially institutionalised theories of interpretation of our actions, then it seems to me we could go a long way to accepting their differences as mere differences of narrative. There are no universal differences in how humans exist in the world.
As we continue to uncover and understand the ways in which the brain enables belief formation and moral reasoning, we must work to identify what the intrinsic set of universal ethics might be. It is a revolutionary idea, to be sure, but clinging to outmoded belief systems and even fighting wars over them in light of this knowledge is, in a word, unethical.
