Skeptophilia (skep-to-fil-i-a) (n.) - the love of logical thought, skepticism, and thinking critically. Being an exploration of the applications of skeptical thinking to the world at large, with periodic excursions into linguistics, music, politics, cryptozoology, and why people keep seeing the face of Jesus on grilled cheese sandwiches.

Thursday, October 25, 2012

Mechanisms, cognitive bias, premonitions, and telepathy

I have a cognitive bias.  When I come across a new phenomenon, and am trying to wrap my brain around it, I need to understand the mechanism by which it works.  If no mechanism is forthcoming, this raises (considerably) the level of evidence I demand before I'll accept that what I'm seeing is real.

I realize that this is, in many ways, getting the cart before the horse.  Rarely in science do researchers discover something, and understand the mechanism by which it works, simultaneously.  Almost always we start out by making some sort of observation that requires explaining, and describe the what of the phenomenon long before anyone is able to give a good explanation of its how.

The problem is that given this bias, this automatically makes me doubt studies that show results that don't seem to have any reasonable mechanism by which they could have occurred.  I'm aware that this could be potentially preventing me from accepting evidence that would be convincing in any other realm, a position hardly befitting a skeptic -- but in my own defense, at least I'm aware of it.

This brings us to today's bit of possibly scientific weirdness -- two studies, just released in the past week, that allege a factual basis for ESP.

The first one, done by a team led by Julia Mossbridge, a neuroscientist at Northwestern University, apparently gives support to the contention that some people experience premonitions.  Mossbridge and her associates analyzed the results of 26 psychological studies, some dating back as far as 1978, looking for evidence that people were experiencing emotional reactions to information they hadn't seen yet.  Subjects were shown photographs that varied in content -- some neutral, some pleasant, some disturbing, some sexually arousing -- and they experienced physiological changes (alterations in electroconductivity of the skin, blood vessel dilation, pupil dilation, EEG readings, and so on) two to ten seconds prior to being shown the relevant photograph.  Mossbridge claims that she has controlled for factors such as the Clever Hans Effect, and has stated, "These results could not be explained by experimenter bias in the normal sense."  Her statistical analysis has placed the odds of the results being due to chance or coincidence at 400 billion to one.

My problem, predictably, is that I don't see how this could possibly work.  I don't see a mechanism.  If you're asking me to believe Mossbridge's results come from some sort of real phenomenon at work, it seems to reverse the temporal order of causality -- placing the effect before the cause.  Causality seems to me to be one of those rock-solid ideas, about which there can't be any reasonable doubt.  But then, that's just all part of my bias, isn't it?

The second study is even sketchier.  In it, a group of neuroscientists from the National Institute of Mental Health and Neurosciences went to Bangalore, India, to do an fMRI on a gentleman who claimed to be telepathic.  In the study, one of the experimenters drew a picture, and simultaneously a control subject and the alleged telepath tried to reconstruct the drawing while inside the fMRI machine.  The telepath created a drawing that had a "striking similarity to the original drawn by the experimenter;" the non-telepathic control's drawing had no resemblance at all.  More interestingly, the fMRI results showed increased activity in the alleged telepath's right parahippocampal gyrus, and no such increase occurred in the control.

This one activates my skepti-senses not only because of my bias against anything for which I can't see a possible mechanism; I also wonder why such a stunning result wasn't published anywhere but the International Journal of Yoga.  But let's pass over that, and attribute that to the known biases that grant funding agencies and peer-reviewed science journals have against anything that smacks of woo-woo.  So even assuming that the study was valid, how on earth could such a thing as telepathy work?  What you're telling me is that somehow, as I draw a picture, my thoughts are creating a change in the electromagnetic field surrounding my head, and you (ten feet away) experience that through the neural connections in your right parahippocampal gyrus, and this makes your visual cortex fire, making you suddenly realize that I'd just drawn a picture of a kitty cat?

I'm just not seeing how this could possibly work.  You'd think that any changes in the electromagnetic field in my vicinity caused by my brain activity would be so weak as to be undetectable at that distance -- especially given that the test subject was inside the giant electromagnets of an fMRI machine at the time!

Of course, many believers in telepathy don't think it's communicated electromagnetically, that there is some sort of "psi field" by which it is transmitted -- but to me, this doesn't explain anything, it just adds one more item to the list of ESP-related phenomena that no one has ever proven to exist.

In any case, the problem is that Mossbridge et al., and the unnamed scientists who fMRI'd the telepath in Bangalore, may well have stumbled upon something that needs explaining.  (Assuming that neither group are hoaxers; I mean no slight to their reputations, but that possibility can never be discounted without consideration.)  If either or both of these results is real, and not a fluke, a hoax, or a statistical artifact, then despite my objection that there seems to be no possible mechanism by which either one could work, we have some serious explaining to do.

But my bias won't be silenced quite so easily.  Despite Mossbridge's claims of a 400 billion to one likelihood against her results being due to chance, and the hard evidence of the fMRI photographs, I just can't bring myself to overturn everything we currently understand about neuroscience, physics, and causality, and throw myself into the Believers' Camp.  I hope, just for the sake of balance, that some scientist or another takes on the challenge of sifting through these studies -- but if I were a betting man, I'd be wagering that neither one will stand up to any kind of rigorous analysis. 

2 comments:

  1. Hi Gordon,

    Julia Mossbridge here. Nice discussion of the paper, thank you.

    I think you're right to be skeptical, but not because of a lack of mechanism. As you point out (very eloquently, I might add), mechanisms tend not to become well understood until an effect is discovered and observed by multiple researchers. Some effects (e.g., gravity) still don't have mechanisms, but are observed by even non-researchers on a daily basis.

    I think you are right to be skeptical because everything we know about everyday experience tells us that causes precedes their effects. Further, as we point out in the paper, the second law of thermodynamics definitely suggests a one-way arrow of time (forward).

    I am skeptical myself, which is why I did the analysis. Right now the results are unexplainable by any means that seem to fit the data, but that doesn't mean they won't be explained in the next day (or year) in a perfectly reasonable way.

    Another possibility is, of course, that these results reflect some kind of information traveling backwards in time. In that case, one possible explanation could arise from quantum effects at the macro level, something that is just starting to be observed in plants...maybe humans next? Who knows.

    One thing I'm sure of -- the explanation will be based in science, not fantasy.

    In any case, thanks for your nice write up!

    Julia

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    1. Hi, Julia! I'm delighted you read my piece; I'm always happy to hear from folks who are on the front lines of research. Your research is fascinating - as I said in another post a while back, true discovery is almost always initiated by someone noticing something anomalous that forces us into a reevaluation of our preconceived notion. If you do find further support for your thesis, please let me know & I'll do a followup!

      cheers,

      Gordon

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