We like to think it’s our choice to help an old lady across the road or push her into the traffic. But an increasing number of scientists say we’re fooling ourselves. Are some of us just hard-wired to be bad?
Neuroscientists are calling it “the most interesting case history in the world” and it involves a nice man who became a paedophile because he had a brain tumour. The life of the gentle, intelligent 40-year-old schoolteacher, known as Mr C by his doctors at the university medical centre at Charlottesville, Virginia, in the United States, first started to go off the rails five years back. Totally out of character, he began visiting paedophiliac websites. Next he was making sexual advances to his young stepdaughter, so his wife had him arrested for child molestation. On the point of going to jail, he complained of severe headaches, and a benign tumour the size of an egg was discovered in the “prefrontal” area of his brain. After the op his paedophiliac urges vanished, and he returned to normal.
Doctors theorised that the tumour had restricted blood supply to the area of the brain associated with impulse control. Last year the tumour came back, and so did the paedophiliac urges. He has had a second operation and, for the time being, appears to be his old decent self.
Most cultures in the world believe that virtue and vice involve an individual’s ability to distinguish right from wrong, and to freely choose one or the other – unless they are insane or acting under unbearable duress or intoxication. The laws of most societies assume moral decisions are made in the conscious, rational mind. But an influential number of brain researchers disagree. They point to cases like that of Mr C to argue that it is not people, or minds, that commit bad acts, but their brains.
As Roy Fuller, one of the men who invented Prozac, notoriously declared, “Behind every crooked thought there lies a crooked molecule.” We would say, “The man raped a child,” but the brain scientist would say something like: “A decrease in the subject’s serotonergic neurotransmission, due to a decrease in his level of serotonin, led to behaviour disinhibition.”
Believing that brains cause responsible acts, good and bad, focuses sharp attention on a rapidly expanding discipline called neuro-ethics: the brain science of morality. Are the scientists about to offer explanations – solutions, even – for crime, brutality and violence? Or are they talking dangerous nonsense?
“What the late 20th century was for molecular genetics,” says Professor Martha Farah, a leading researcher in neuro-ethics at the University of Pennsylvania, “the early 21st century is proving to be for neuroscience.” Rapid advances in non-invasive brain-imaging are enabling scientists to study moral and emotional processes, including paedophiliac behaviour, in individual brains.
We already have the drugs to enhance mood (lithium and Prozac), concentration (Ritalin) and memory (Aricept). Will we one day have a drug to regulate moral behaviour? “It brings closer the untoward potential consequences of biologically engineered morality,” says Dr Laurence Tancredi, a psychiatrist who practises law in New York.
He predicts a “new society” in which “moral” aberrations will be predicted, and corrected by drugs. “Neuro-ethics,” says Professor Nikolas Rose of the London School of Economics (LSE), “is raising important questions about how we configure the boundaries of the normal and the pathological, the treatable and the acceptable… the kind of humans we want to be.”
Crude connections between the brain and our behaviour have long been familiar. Take the railroad worker Phineas P Gage, a decent chap who in 1848 suffered a prefrontal-lobe injury when an iron rod shot through his skull while he was dynamiting a tunnel in Vermont. He survived but became a foul-mouthed lout. Then there was the 1979 “Twinkie defence” trial, in which Dan White, who had shot dead the mayor and the city supervisor of San Francisco, George Moscone and Harvey Milk, was found guilty of manslaughter rather than murder because, as the public saw it, the jury accepted that White had simply eaten too many cupcakes that day, the sugar in his brain turning him into a killer.
In 1992, also in America, a Mr Weinstein was charged with strangling his wife to death during an argument and throwing her body out of the 12th-floor window of their apartment to make it look like suicide. A positron emission tomography (Pet) scan, revealing “sliced” images of Weinstein’s brain, showed up an arachnoid cyst. His psychiatrist claimed that the tumour had caused metabolic imbalances leading to poor impulse control; allowing the scan led to the lesser plea charge of manslaughter. Three years later, a charity manager, William Aramony, was charged with embezzling hundreds of thousands of dollars to fund a lavish lifestyle. But his defence lawyers argued that it was his brain that stole the money and not him. He could not form the requisite criminal intent for embezzlement, argued the defence, because his brain had been shrinking during most of the late 1980s and early 1990s, a fact that could be substantiated by a magnetic resonance imaging (MRI) scan. In the event, the prosecution agreed to a plea bargain favourable to the defence.
It is universally accepted that alcohol and drugs can be detrimental to moral behaviour. Evidence that our diet can also alter our actions has been demonstrated in a research trial at a maximum-security British prison when a zinc supplement was added to prisoners’ food, culminating in a significant reduction, it was claimed, of the rate of reoffending. At a recent symposium it was seriously proposed that zinc be introduced into drinking water, like fluoride, to combat criminality.
Quite how cupcakes, or zinc, make good people bad and bad people good is by no means clear. But with every passing week, scientists learn more about the complex action of brain chemicals known as neurotransmitters on our emotions and our behaviour, including learning, memory, decision-making and anger. At the same time, brain scans taken while people perform a variety of cognitive and emotional processes, including lying and fantasising about sex, have located specific areas in the brain crucial to decision-making. What neuroscience is telling us, moreover, is that while brains are broadly similar, they are also highly individual. There are crucial processes in early foetal development that owe less to genes than to “epigenetic” (beyond genetic) competition between migrating cells, thus guaranteeing the uniqueness of each member of the human species – even in the case of monozygotic twins.
Arguably, liars, thieves, muggers and paedophiles, like saints, philanthropists and Good Samaritans, are not bad or good – just “different”, their brains having disposed them to behaviour outside the moral norm. The eminent American neuroscientist Professor Terry Sejnowski once told me his work had made him less prone to judge others: “Neuroscience teaches us that all our drives and compulsions are unequal.” The religious doctrines of original sin – meaning we are prone to prefer wrong by nature – conscience and free will have been eroded by rationalism, science and secularism over the past two centuries, yet a powerful belief in responsibility for our actions remains – in family life, friendships, soap operas, newspapers and the criminal-justice system. The tendency to find excuses for bad behaviour was inherent in Freud. But it was neuroscience, which took off in the mid-1980s, that accelerated the process.
With the collapse of communism, a large slice of American national science funding was diverted, as part of the post-cold-war peace dividend, into the biology of the brain. The anticipated payoff was the promise, touted by the pharmaceutical industry, that the US economy could save $350 billion a year by reducing brain-related problems including Alzheimer’s, depression, workplace stress and, above all, violence. The 1990s came to be called the Decade of the Brain. This brainstorming was sweet music to thinkers bent on putting to rest for ever the ancient notion that our minds are separate from our bodies. As Patricia Churchland has put it, “human beings are not controlled by a spooky-stuff soul.” Churchland, who styles herself a neuro-philosopher, announced a new age in which brain states would explain the human condition.
One of her gurus was the late Nobel laureate Francis Crick. At a neuroscience meeting in Orlando in 1996, I listened to Crick declaring: “Your sense of personal identity and free will are in fact no more than the behaviour of a vast assembly of nerve cells and their associated molecules.”
Later he invited me to tea at the Salk Institute in La Jolla, California, where he asserted, waving a blue teapot in the air: “Neuroscience will give us a more authentic causal explanation for human behaviour than unscientific and hence unreliable folk psychology.” By folk psychology he meant history, fiction, memoir, poetry, philosophy and religion.
Crick was not alone in believing that the whole of our mental life, including our choices and our sense of responsibility, is no more than a kind of determined chemical software program running in a computer-like brain. Being good means an efficient program; being bad – paedophilia, rape, theft, lying, murder – means a defective program. Against this background, it seems feasible to correct a defective program with mind-altering drugs like Prozac.
Philosophers, too, have long suggested that personal responsibility is an illusion. The British professor Sir Freddie Ayer, famous for his BBC Brains Trust stints, claimed there was no such thing as good or bad acts: merely feelings of “boo!” or “hurrah!” The French philosopher Jacques Derrida taught that a person was just a series of stories from which emerges the illusion of a self – and how is one good or bad without a self?
But the most notorious attack on individual responsibility was the result of a wacky research programme, still in progress, devised by a lean individual in big glasses called Benjamin Libet. Libet sought in the early 1980s to prove that our brains and nervous systems commit us to a choice before we are even conscious of taking it. Volunteers were asked to flick their wrists, while noting on a special clock the precise point at which they made the decision to do it. With the use of an electroencephalogram (EEG), Libet found that the nervous activity, known as readiness potential (RP), preceded the action by up to 400 milliseconds: that is, almost half a second. The philosophers Daniel Dennett and Daniel M Wegner find confirmation in Libet’s research for their argument that free will is essentially a fiction; Wegner calls it a “cognitive feeling”. In 2004 another research team claimed to have repeated Libet’s findings at Oxford University, using a scan known as fMRI, functional magnetic resonance imaging. The researchers identified three precise points in the brain where blood flow intensified when the volunteers deliberately moved a finger in three sections of the prefrontal area: 200 milliseconds, or a fifth of a second, before consciousness of the intention took place.
For Dennett, morality has been hard-wired into us through evolution. Behaviour that has distinct survival advantages for our species – such as generosity and helping others – we have come to call “good”; that which doesn’t, such as murder, we have labelled “bad”. Tancredi, the lawyer psychiatrist and author of a new book, Hardwired Behaviour, believes that morality acquires its timelessness and universality from the brain that all humans share: “The limbic structures of the brain, often referred to as the old brain – old in the evolutionary sense – are the physical circuitry for our emotional responses, fear, disgust, guilt, to the environment.” He believes that these circuits work in partnership with the prefrontal lobe, the area of the cortex beyond the forehead that considers the facts and checks them against a particular set of emotions. “We feel shame, for example if we fail an exam through staying up all night at a party,” he argues, “because we have been trained from childhood to understand that our parents and friends will look disparagingly at our failure. Over time we internalise that emotional response and automatically feel shame whenever we are not successful.”
Under the scrutiny of neuroscience, it is possible to medicalise pretty much anything. “Some of the seven deadly sins,” claims Tancredi, “have already been shown to be affected by biological factors in varying degrees, and in some cases, the individual may have little power or free will to prevent them from happening.” Gluttons, for example, or excessive eaters, may be suffering from a condition whereby hunger and satiation messages are being sent to a part of the brain associated with reward circuits in addiction. Hence obesity may result from abnormalities over which individuals have no control. The slothful may be suffering from depression that results in a lack of desire to act. “This is clearly a biological condition,” says Tancredi, “as we know that in depression major neurotransmitters, in particular serotonin, have been decreased in the synapses.”
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All the survey on The Timesonline
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