Wednesday, December 13, 2006

A Curious Effect of Vibrating Phones

Sometimes -- not often, actually -- I set my cell phone on vibrate. I keep it in my left front pocket. Now, it seems to me that I feel vibrations at the top of my left leg periodically, even when the phone is not vibrating, even when the phone is not in my pocket at all. I was reminded of this a few days ago when a colleague remarked on a similar experience.

My question is: What's going on here?

Here's one possibility. Primed to feel subtle vibration against that part of my leg, I sometimes misjudge whether there is vibration. Well, maybe! But here are my qualms. On the one hand, if the judgment here is supposed to about the vibration of an external object against my leg, I don't think I'm actually (or at least not usually) making that judgment. Rather, I'm judging that there's a vibrating feeling resembling the feeling when an object vibrates against my leg. But -- and this is the "other hand" -- if the judgment is just about my experience, it seems at least a little strange to say that I'm wrong in that judgment, i.e., wrong that I am experiencing a buzzing feeling of a certain sort -- though maybe!

Here's another possibility: My body is constantly -- or frequently -- abuzz with vibrations, or vibration-feelings, of various sorts, but I rarely notice them. Having the cell phone has attuned me especially to vibrations at the top front of my left leg, so now I notice them there, whereas I didn't before. Quite possibly so! But that's a pretty rich view of experience. It doesn't seem now, as I've been sitting here typing, thinking about buzzing feelings, and even pausing occasionally to reflect on whether anything is buzzing, that my bodily experience is so rich with sensation. On the other hand, it has only been about 20 minutes. If I feel five hundred buzzes a day, and one -- the one I notice -- is in that exact location on my leg (which I'd estimate to be about 1/500 of my body surface), then I should expect a buzz only about... well, doing the math (assuming 16 waking hours), actually about every two minutes! Hm!

Or maybe the buzzing is a new experience, arising somehow from the fact that I have a readiness to feel buzzing in the location, and accurately apprehended as an experience when it occurs. I do now occasionally "buzz" at the top of my leg, as a result of carrying that phone in my pocket, whereas I didn't before. Though this also seems slightly strange, it is perhaps the most appealing possibility -- intellectually appealing I mean! At another level, I'm not sure I like the idea that I've added a buzz to my stream of somatic experience....


Anonymous said...

Hi Eric...

When I was younger, it was interesting to me to look upon surfaces with "noisy" textures, and just look while different shapes "popped-out" from the noise... Usually some strange faces, animals etc...
Sometimes I used to take a pen and draw what I saw in the noise of the texture.
The much noisier the thing is, the more different kind of things can be "drawn in the noise", our perception somehow succeeds to find (by itself?) some form, by making more salient some parts of the noise then others.

Anyway... here is another possible explanation, based on two assumptions:

a)Your body is not "abuzz with vibrations", but there is a constant noise in our experience.
b)The repeated experience of the buzz created by the phone, creates some kind of background expectation of such thing to happen. So to say, there is constant "buzz recognizer" installed.

So, based on those two assumptions, the theory would be that in some situation the noise is such that some part of it triggers the "buzz recognizer", and the "buzz recognizer" further "draws" the buzz into the noise.

BTW, In thinking about this issue few years back I started wondering if our power of imagination really creates the imagined things out of nothing, or maybe that it is merely using some noise which is present all the time in our perception, and that it is just making more salient some part of the noise than the other.

I don't know if any experiments on the connection between noise and imagination/perception are done in psychology, but if you know of some, it would be interesting to hear about them.

Anonymous said...

Huh, I posted something yesterday but something must have gone wrong. Anyway, Eric, I'm glad you posted this because I thought I was going crazy. I've experienced this phenomenon often recently (to the point I take out my phone to check if there's a call). I have no explanation for it. I assumed the cause was external (i.e., the phone was actually buzzing slightly for some reason), rather than in my head. Perhaps we are hallucinating the buzz because we really want to have people call us, and it's easier to hallucinate a mild buzz than a ring tone?

Eric Schwitzgebel said...

Hi, Tanasije -- thanks for your thoughtful and interesting comment (as usual!). The possibility you develop is a nice one, very plausible, and a kind of combination, I think, of the second and third possibilities described in my post. There is indeed an interesting literature on "noise" in psychology -- the literature on "signal detection theory". Pretty technical stuff, but I think ultimately harmonious with your suggestion here. As one is primed or rewarded to detect a signal of a certain sort, one is more likely to interpret what might be random noise as the signal. But signal detection theory is generally silent on the issue of whether that noise is consciously experienced as signal or whether it is experienced as noise but misinterpreted as signal (for those of us who think there might be an important difference here).

Eddy, if you're crazy there's a lot of us crazy! I wonder if it is easier to hallucinate a buzz than a tone; interesting thought. I do think one can get confused about / hallucinate / confuse signal and noise regarding sounds, too. Most parents will know the experience of being unsure if they're hearing a faint cry or rustling from the next room. Maybe with phones the signal is just too different from noise for their to be any mistake, whereas the buzz is closer to the limen of perception...?

Sorry, by the way, if your comment was dropped. I find Blogger sometimes a little frustrating that way. When I write a long comment (like this one), I always copy [ctrl-A, ctrl-C] it in case Blogger hangs, then check to make sure it posted.

Anonymous said...

Hi Eric,

Interesting post!

I'm sad that I didn't get to be the first to bring up signal detection theory, but I'm glad someone did. Could you spell out a bit more why you think it doesn't help explain what you thought needed explaining?

Anonymous said...

I sometimes have the auditory equivalent of this when I am wearing headphones (but almost never otherwise). I will think I hear the phone ringing, but when I remove the headphones to check, I (often) find that I have been mistaken.

I have also had the false vibration experience. In fact, on one occasion I initially was unsure whether the phone was buzzing or not. As soon as I turned my attention to it, I REALLY felt the vibration -- almost as though it had switched from mild vibration to "I'm going to vibrate every atom in your body".

I think attention and expectation change the way we interpret stimuli. Perhaps enough that normal pressure or rubbing from clothing, or mild vibration from the car, etc., can lead to an interpretation of such stimuli as the vibration of the phone? I think something similar goes on in the auditory version -- background noise, whether in the audio signal coming through the headphones or ambient noise, gets interpreted as a ringing. I never mistakenly hear a ring or feel a vibration if I know I am sans phone.

Eric Schwitzgebel said...

Thanks for your comments, Eric and Pete! Eric's interesting characterization of his experience displays just the ambiguity -- which is fine, maybe even intended -- that the signal-detection theory literature does. In some circumstances, we "intepret" some environmental (or bodily) noise as a signal (e.g., a buzz a ring). But what is the conscious process associated with such interpretations? That's still wide open, isn't it? Is there no actual experience of buzzing/ringing? Are there really many such buzzings/ringings and simply most of them pass unnoticed because we don't interpret them as relevant? Or does the fact that we're primed to feel or hear something mean we sometimes create experiences of buzzing or ringing that otherwise wouldn't have occurred?

Now there may be some justification for a Dennettian or quasi-Dennettian skepticiam about whether such questions are really distinct. But if you think, as I do, that they are indeed distinct, signal-detection theory doesn't address them.

Anonymous said...

I, too, used to get these buzz hallucinations, but don't anymore as I don't carry my phone that way now. I'd guess it's an attention thing; I've told my mind that a buzz at the top of my leg is important, and it responds by interacting more with this part. Perhaps it's also influenced by low levels of paranoia (as with pulling doorbell or telephone rings out of the music being heard on headphones) - a constant nervousness that you're missing a call.

embaya James said...

i also has been experiencing this even though i no longer carry my phone in my trouser pocket