Thursday, October 09, 2003

 

God damn it. I wrote a long post, and Safari "unexpectedly quit". Totally random, I'm sure.

I went to the departmental colloquium yesterday, despite having no idea what it was going to be about. I couldn't decipher the title: "Precognitive Habituation: Replicable Evicence for a Process of Anomalous Cognition". (Huh?)

Maybe you're smarter than me. Forget the context, and just think about the first word in the title. Precognitive. Okay, shorten it to "Precog". Yep, you got it. The talk was about "precognition", which is to say, seeing the future.

The speaker was Daryl Bem, apparently a well respected social psychologist and tenured professor at Cornell. There's a well established psychological phenomenon called the "mere exposure effect", observable in all kinds of domains, where just being exposed to something once will make you like it more when you encounter it again. So, for instance, if you show a subject 15 pictures, randomly selected from a group of 30, and then show her all 30 a day or a week later, she'll say she likes the 15 she saw before better, on average, than the 15 she didn't see. There's another phenomenon, which goes the other way, called habituation - this is actually the basis for most infant studies in our lab. If you show a subject the same thing over and over again, they'll get bored with it; babies will look longer at a new, novel object or event than they will at an old, frequently seen event, and we use this as a dependent measure in tests to see what kinds of things babies can "tell apart". It works with adults, too, and does nifty things like make very appealing things less appealing (think porn) and make very unpleasant things less unpleasant (if you see gunshot wounds every day, they become less shocking and disturbing).

Anyway, what Bem did was just flip pretty well established psychological experimental methods around, temporally. Ran 'em backwards. That is, showed subjects pairs of images, asked them which they liked better, and then - randomly - flashed one of the images multiple times, for subliminal durations. Then he analyzed the data to see whether there was a tendency for you to pick the one you're about to be exposed to.

There's a write-up on his website that closely matches the substance of his talk. His 1994 Psychological Bulletin paper is a more finished product, and is a good read. He also offered this as a reference on research done in the field: Dean Radin's "The Conscious Universe".

Okay, I gotta go to lab meeting.

posted by Miles 8:51 AM