Research on parapsychology is largely taboo in academia, but two Harvard scientists recently set out to settle, once and for all, the age-old question: Is extrasensory perception, or ESP, real?
Their sophisticated experiment answers: No, at least, not as far as they can tell using high-tech brain scanners to detect neural evidence of it.
In this month's Journal of Cognitive Neuroscience, a respected academic journal devoted largely to brain imaging, Harvard's Samuel T. Moulton and Stephen M. Kosslyn publish findings aimed to resolve the parapsychological debate that has simmered at least since the time of their Harvard predecessor, William James, more than a century ago.
The study was the first to use cutting-edge brain scanning called functional MRI to address the question of whether ESP powers exist, said Moulton, who has been interested in ESP research since he stumbled across some previous supporting scientific research that he found impressive.
His study was designed to simultaneously detect three types of extra-sensory powers: direct knowledge of someone else's thoughts (telepathy), knowledge of the distant physical world (clairvoyance), and direct knowledge of the future (precognition).
Each participant was placed in a brain scanner and sequentially shown two photographs. At the same time, the participants' friend, partner, relative or identical twin was shown one of the photos -- the ESP image -- on a computer screen in another room and asked to mentally "send" the image to the participant. The participant had to guess which of the two photos was being "sent" from the other room, and then was shown the ESP image again to test precognition.
If ESP were real, the brain should have responded differently to the ESP image -- recognizing it as familiar. But, in all cases, when the researchers compared the scans, they saw precisely the same pattern of brain activation for the ESP and non-ESP images, meaning the brains responded the same.
"Our results showed no difference, and therefore our results are evidence against the existence of ESP," Moulton said.
But will these null findings change anyone's opinion of ESP? Surveys have found that about one-half of the general population believes in ESP, even though its existence remains highly controversial.
Says one posting at a science-oriented blog called "Ionian Enchantment," "This probably goes without saying, but I sincerely doubt any true believers will be convinced by this evidence."
Some supporters of ESP argue that the mind is not simply a product of the brain, but that it has metaphysical or spiritual dimensions beyond the actions of neurons and synapses
Moulton's findings also face the classic scientific problem that it is a great deal harder to prove that something does not exist than that it does.
"The absence of evidence is not the same as evidence of absence," said Daryl Bem, a psychology professor at Cornell University who has done experimental research on parapsychology and says the evidence of various forms of ESP is "quite strong."
Moulton and Kosslyn are very competent researchers and their experiment was "very clever," Bem said. But their negative results may simply mean that they need to tweak their methods more, he said. Perhaps, for example, they should have used people already established as talented at ESP, rather than randomly recruiting subjects, he said.
Moulton said that bringing in mediums or others who claim to be psychic might have opened the experiment up to the possibility of fraud, but he invites other researchers to study self-proclaimed psychics using his method.
Moulton, a Harvard graduate student who is doing his dissertation on the effects of meditation in the brain, does not plan to pursue further work on parapsychology, abandoning an interest of nearly a decade that netted him a prize for best thesis when he was an undergraduate.
"I've done my part," he said. "You do study this stuff at your own professional peril."
Carey Goldberg can be reached at goldberg@globe.com.
