The murder conviction of an Iowa man was overturned last year by that state's highest court on the basis of a new technique that has some scientists wondering if we are entering a strange new world that may ultimately redefine what it means to be a human.
Terry Harrington had served more than two decades for the 1978 murder of a Council Bluffs night watchman when the court reversed the conviction. Something called "brain fingerprinting" convinced the court that the "records" in Harrington's brain did not match the scene of the crime or the details of the case.
He could not have killed the watchman. If he had, parts of his brain would have emitted an electrical response that showed some recognition of photographs and evidence pertaining to the crime, according to the court.
The case is particularly significant to neural scientists because it is part of a growing body of evidence suggesting that we are entering a new realm of delving into the inner workings of the human brain. That could raise profound ethical questions that will make the current debates over genetic engineering seem pale.
All of that has stirred the concerns of a number of scientists, including Martha J. Farah, a psychologist with a varied background who now directs the University of Pennsylvania's Center for Cognitive Neuroscience. Farah, who earned a bachelor's degree in metallurgy and a doctorate in psychology from Harvard and then entered the young field of neural science, believes we are treading in dangerous waters in a field we have only barely begun to understand.
"Technical progress is making it possible to monitor and manipulate the human mind with ever more precision through a variety of neuroimaging methods and interventions," she says in an essay in the current issue of Trends in Cognitive Sciences. While that may lead to wonderful advances in such things as treatment for the mentally impaired, it also will certainly lead us into areas where no human has gone before.
We are already able to enhance a normal brain through chemistry to make it perform better. All sorts of drugs help people get through difficult periods by conditioning their minds to chill out. Even electric elements attached to the skull can change a human personality.
And if we can peer deeply enough into the brain, we ought to be able to figure out who among us is likely to molest a child, blow up a police station or commit an act of terrorism. That's one reason the Central Intelligence Agency is helping fund an Iowa company that developed the brain fingerprinting technology that gave Harrington his freedom.
But there's one basic problem with that, according to people like Farah. We don't know squat about how the brain really works. New diagnostic tools have helped scientists determine which parts of the brain "light up" in response to various stimulations, so we are learning more about what does what.
But there's much debate over why and how.
So we're on a "slippery slope," as Farah puts it.
"For the first time it may be possible to breach the privacy of the human mind, and judge people not only by their actions, but also by their thoughts and predilections," she writes. "The alteration of brain function in normal humans, with the goal of enhancing psychological function, is increasingly feasible and indeed increasingly practiced."
There is a trend, she says, to do for the brain what cosmetic surgery can do for the nose, even though we know a lot more about our noses than we do about our brains.
"Brain-based enhancement involves intervening in a complex and poorly understood system, and the likelihood of unanticipated problems is consequently higher," she says.
In other words, in an effort to make our minds sharper, we may really dull the equipment. You don't have to look beyond the headlines to realize how wrong science can be, particularly about the effect of drugs.
What may be especially troubling to us common folk is the ability of scientists to peer into our brains without our knowing what they are really looking for. Participants in a study might be told the researchers are looking for some benign reaction to a child in shorts, for example, whereas the investigator may be really trying to determine whether the subject is prone to child molestation.
And as Farah points out, the findings may seem valid at the time, but advances in this rapidly changing field may prove otherwise somewhere down the road.
By the way, Farah says that technique has already been used in "neuromarketing," or the attempt to find out what someone really thinks about a product by monitoring brain waves. In one demonstration, she says, the technique revealed the importance of brand name in choosing whether someone is likely to pick one soft drink over another.
It may seem that manipulating our brains to enhance our mental skills is still off in the future, but it's already here. A number of drugs are now in widespread use to help users focus on a problem, improve their memory or run a more efficient organization.
The drug Ritalin, for example, was designed to treat children with attention deficit disorder. But it is now in widespread use by college students, particularly during finals. Aricept and others are used to enhance normal brains, not just treat those that are troubled.
People like Farah are now beginning to ask if that takes us in the right direction. It places enormous pressure on students to use drugs in order to compete with others who are using them, thus widening the gap between those who can afford them and those who can't.
And if someone you love is on a mind-altering drug, do you love the person, or do you love the person whose mind has been altered?
Where will all this lead? Neural scientists think it will lead to a better understanding of how the brain functions, and possibly to acceptance of the idea that the brain is nothing more than a biochemical piece of machinery, and everything it does can be explained by those mechanical functions.
That being the case, is personality just the result of gears grinding together? Is there a soul or can everything be explained through the interaction of neurons and electrical and chemical interactions? What does it really mean to be human?
Farah, who is committed to learning more about how the brain works, and how we can change it, raises a much more basic question.
Do we know where we are going?
Lee Dye's column appears weekly on ABCNEWS.com. A former science writer for the Los Angeles Times, he now lives in Juneau, Alaska.