Why"double blind"tests don't work:brain?

I have always thought that the difficulty people, including myself, have with this has to do with expectations and perceptual sets.

I think, similar to Elizabeth's comments, that when we are expecting to hear a difference and are trying to be analytical our brain tries to force the information from our senses into our existing experience/thought structures and we end up denying our senses because of our tendency to force experiental information into existing perceptual sets. This is the same reason that camoflage(sp?) does not necessarily have to mimic the visual background it resides in to be effective. It just has to break up the image of an object and our brain will integrate the object into existing perceptual sets.

From my intro to psych class back at the cow college I seem to remember that this concept underlies the use of Rorsach(sp?)or inkblot tests. They attempt to make you divulge your perceptual sets in response to a picture.

On the other hand when we are just listening/viewing without a goal in mind, our perceptual sets are not as active. For instance, we would see the pictures in the inkblot test as inkblots and not pictures. In this mode we hear/see what is really there instead of trying to force predetermined structure on our senses.

While I agree that we listen differently based on our objectives in listening I do not think it is a "hardware" problem having to do with the structure or operation of the brain. I think its a "software" problem that prevents us from being accurate and objective

I would really like to hear from anyone with some training in this area.

Ignatz, I'm interested in what you have to say, but am not quite sure what you mean by software vs. hardware. I didn't quite get the connection with what you had just been saying. Please explain.

One comment, when we are listening/viewing without a goal in mind, our pereceptual sets are still quite active, perhaps even more so, although not in the same way. Anyway, it's all based on very limited empirical knowledge with much variation between individuals...

BTW, right on about the Rorschach. I administer this all the time. It's one of a class of assessment instruments called projectives, because, as you say, there's nothing really on the card but a bunch of ink, and what people report seeing is thought to represent their psychological themes, which they "project" onto the image. However, these themes may be verbal, emotional, kinesthetic, whatever. Even looking at the pictures without a goal, images are projected onto the blot, just as our cognitive, emotional, and other biases color the physical stimulus when we listen to music, regardless of what frame of mind we are in. When a person reports just seeing blots of ink, the traditional interpretation is that they are not being forthcoming and/or are 'defending' against their psychological processes, either consciously or unconsciously. I've tried it myseslf - you really have to try hard to stop from seeing things in the blots. It's not that they're really there, it's just that we're hard-wired pattern-detectors. All right, I'm blathering, sorry. Anyway, I can't emphasize enough (so I won't really try) that there's not enough solid data to back up music-related brain-behavior phenomena hypotheses in any real firm way. However, I'll run this whole thing by my neuropsych supervisor and the hospital neurologist and see what they have to say!

I guess I do not agree. Years ago when I first got into upgrading cables I started with an interconnect from my CD Player to integrated amp. I went to a dealer I trusted who who could duplicate my system (and they did). I was totally blind; the salesperson (an electrical engineer by training) switched cables around for me to listen to without telling me what cables he was using or how much they cost. I found out later they ranged in price from $70 a pair to $400. I would respond with: "I like" or "do not like" these cables compared to the ones that came before. I had him switch back to the other cable to confirm I liked it better. He did a lot of switching around and would eliminate the ones I did not like. I eventually settled on a cable which he revealed to be a Nordost Blue Heaven; about in the middle based on price. There was one cable I hated that smeared the sound of that setup which I later found out was a Kimber cable that is very popular seller. So blind testing worked for me.

Secondly this is how HiFi Choice Magazine basically does their panel reviews, which for me are the best I have found for getting a feel for budget audiophile gear before going for a listen.

DBWL-

Thanks for your comments. What I mean by hardware is the physical parameters of your brain/nervous system, like the product specs for a computer. The software part is the information processing routines inside your head. It is my understanding that we filter the information provided by our senses to add meaning, prioritize information, etc. so that what I perceive is not what you perceive, what I perceive is not what I perceived when I was a child, etc. I guess my point would be that we use different filters in different situations, and the filters we use are selectable and can be modified.

As an example when I was young I used to hunt out in the vast wastes of West Texas. There was a rancher out there who could see a deer totally hidden inside a bush at about a thousand yards. He didn't have better vision, in fact his vision sucked.He told me he could see the deer because he wasn't looking for a deer he was looking for a piece of a deer; the tip of an antler, an ear, a patch of hair. I practiced this and got to where I could almost find all the deer he could find. I had developed a new piece of software/searchtool/filter. It still wasn't my default software as it required conscious action to use it, but my perception had been radically altered without a change in the physical structure of my processor (brain) or the input (sense info)

I think similar things happen when we listen to music for enjoyment vs. listening to equipment that happens to be producing music. In the first we are looking at a landscape and in the second for deer. I hope this has been coherent.

Thanks Ignatz. Good example. Now that you explain it again, it does remind me of certain cognitive models, although there are many models that blend the "software" and "hardware" components such that they're not really separate. I wonder if we'll ever know...

Anyway, the real reason I'm resposting is that I wanted to comment that I actually agree with Sugarbrie. I've done A-B testing (and other variants: a-b-a-b, etc.), and it's worked pretty well for me. My wife and I use it to select components, and we've found good test-retest reliability doing it. It does make me curious about why so many of us have this experience and so many experts (Dunlavy, Kurt from Velodyne, etc.) report the opposite, which is I guess why Elizabeth started the post! And I do enjoy theorizing about our brains...