Scienceblogging.com has a story up claiming that Harvard scientists have resolved the question of ESP – it does not exist:
The scientists used brain scanning to test whether individuals have knowledge that cannot be explained through normal perceptual processing.
“If any ESP processes exist, then participants’ brains should respond differently to ESP and non-ESP stimuli,” explains Moulton. “Instead, results showed that participants’ brains responded identically to ESP and non-ESP stimuli, despite reacting strongly to differences in how emotional the stimuli were and showing subtle, stimulus-related effects.”
…Does this conclusively prove that ESP does not exist? “No,” says Moulton. “You cannot affirm the null hypothesis. But at the same time, some null results are stronger than others. This is the best evidence to date against the existence of ESP.
I’m not sure I get the whole premise of the experiments, which appear to be making broad assumptions about a (possible) human ability and then testing those assumptions – namely, that there will be a difference in the brain scans. But I’ll have to read the actual paper before I can offer any detailed comments.
However, parapsychologist Dean Radin has commented on the new paper on his website:
I congratulate the authors of this paper because unlike many who hold strong opinions about this topic, they actually conducted an experiment. However, I disagree with their assertion that this single study resolves anything. Like any new experiment, all it really does is raise new questions.
There are so many points I could respond to in this paper that I was tempted to write a comprehensive reply. But then I remembered that I’ve already written one. It’s called Entangled Minds, which apparently these authors have not read. Nevertheless, a few comments:
1) The authors overlooked four previously reported fMRI psi studies, all four of which reported significant results.
2) Compelling personal psi experiences are dismissed as fallacious beliefs due to cognitive biases. I fail to see how one or more of the known cognitive biases can conceivably explain even the example they provide of a crisis telepathy experience, to say nothing of thousands of similar experiences. Obviously if someone was constantly reporting such experiences, but only one in a thousand times the experience was verifiable, then such anecdotes wouldn’t carry much evidential value. But that is not the case. These are often once in a lifetime experiences, and they shatter previously held beliefs. The irony here is that a case can be made that one of those experiences started the neurosciences!
3) The authors made a common mistake by asserting that independent ganzfeld meta-analyses failed to successfully replicate, citing Milton & Wiseman (1999). Unfortunately, that meta-analysis, which is often used to cast doubt on the repeatability of the ganzfeld results, was statistically flawed and underestimated the overall p-value. When corrected, in fact it did result in a significant overall hit rate.
4)One participant out of 16 showed significant fMRI differences consistent with the psi hypothesis. The authors examined three alternative explanations for this result, and concluded that idiosyncratic responses accounted for the significant results. Unfortunately, this explanation reveals a flaw in the underlying design of the entire experiment. If it is possible to dismiss one individual’s results as an artifact, then there is no reason to have confidence that the rest of the data is artifact-free.
5) The experimental task is new, and complex. As far as I know, there is no precedence justifying why we think this procedure might work at all. This reminds me of a paper published in The Humanistic Psychologist a few years ago in which two skeptical psychologists reported a series of eight ganzfeld experiments, which overall produced a significant result. They did not like this outcome and so they conducted another study using a new, untested, ad hoc design, and it resulted in a significantly negative outcome. They then used that last study to dismiss the results of the first eight studies. In the present case, explaining away the one participant who showed a significant result also potentially explains away all other significant results, in which case why did they use this design in the first place?
I noted with interest as well that the research was partly financed from the Richard Hodgson Memorial Fund.
