Harvard psychologists have released a study that they say provides the most convincing evidence yet against the existence of extrasensory perception (ESP).
In a study published in this month’s issue of the Journal of Cognitive Neuroscience, graduate student Samuel T. Moulton ’01 and Psychology Professor Stephen M. Kosslyn used functional magnetic resonance imaging (fMRI) to assess whether individuals can have knowledge that does not come from normal perceptual processes. This focus on the brain sets their study apart from previous ESP research.
In the study, researchers tested three types of ESP: telepathy, clairvoyance, and precognition.
The procedure involved participants viewing sets of photographs while inside an fMRI scanner. Some of the pictures, designated “ESP stimuli,” were also presented to the subject via the different forms of ESP. Stimuli shown telepathically were presented simultaneously to another person—the subject’s relative, romantic partner or friend—in a separate location. Stimuli presented by clairvoyance, the ability to perceive distant things or events, were displayed on a computer located outside the subject’s field of vision. Finally, pictures presented through precognition, the ability to see into the future, were shown to subjects at a later time.
According to Moulton, if ESP existed, the brain would respond differently to pictures designated as ESP stimuli and non-ESP stimuli. Theoretically, pictures perceived through ESP should produce a pattern in the brain similar to ones produced when an individual sees a previously encountered stimulus.
Instead, Moulton found that participants responded identically to both stimuli types, resulting in the lack of a statistically significant difference that is referred to as a “null result.”
Moulton said null results have made previous ESP research difficult to interpret, but that he wanted to design an experiment that would give information independent of whether or not it produced null results.
“We didn’t find anything, but we didn’t find anything in an interesting way,” he said.
Moulton said he was initially inspired by research he conducted for his senior thesis, which demonstrated that brain activity is affected by previous exposure, even when this exposure is subconscious.
When asked why people believe in ESP, Moulton said he believes that cognitive biases can result in people interpreting events in a paranormal way.
“We’re hard-wired to see patterns in things that are probably random,” he said.
He acknowledged that while null results can never be used to conclusively prove that ESP does not exist, he was glad to have done his part toward settling the age-old debate.
Aside from getting published, Kosslyn said that the study also provided him with a Christmas present to give.
“I got my mom’s brain on the cover of the journal,” Moulton said. “She participated in the study, and then they put her scan on the cover, and that was her present.”
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