Mundane Cyborg: more on phantom ring, or “who put the Oh! in Neuroplasticity?

Mundane Cyborg: more on phantom ring, or “who put the Oh! in Neuroplasticity?

Today I was listening to NPR’s radio show Fresh Air, when V.S. Ramachandran's Tales Of The 'Tell-Tale Brain” came on. I’d heard Dr. Ramachandran interviewed before; he is a neurologist at the University of California, San Diego. He was talking about his new book, The Tell-Tale Brain, which cites case studies that
“illustrate how people see, speak, conceive beauty and perceive themselves and their bodies in 3-D space.” The interviewer wanted specifically to know about something I’ve grown quite interested in: the issue of “"phantom limb" and what it reveals about both the mind, and (potentially) about how our minds may react to prosthetics that are not originally limbs but which may begin to act that way.

The interview (which can be found at http://www.npr.org/2011/02/14/133026897/v-s-ramachandrans-tales-of-the-tell-tale-brain) focused on a few core ideas. First, many people who’ve lost limbs and/or had them amputated suffer from chronic phantom pain. Originally scientists thought the pain was caused by peripheral nerves (and nerve damage) near the lost limb. But Ramachandran proposed that phantom limb pain might be caused by changes in the brain. He says in the interview,

[It] was based on an idea that there's a complete map of the body's surface on the surface of the brain. So every point on the body's surface has a corresponding point in the brain. Now the curious thing about this map is, even though it's continuous, the face area of the map is right next to the hand area instead of being near the neck where it should be.

Several things interested me about what he found:

1. Ramachandran found that the brain can literally remap pain can “refer” to another place, so that touching a blindfolded amputee’s face revealed that the amputee felt the touch as touching their phantom limb.

2. This means that (as is assumed now, but was controversial until very recently) that the brain is constantly remapping itself, and is not so fully determined at birth. Our brains aren’t as genetically fixed as we thought; instead, he asserts, “Even the basic sensory map in the brain gets completely reorganized in a matter of weeks. This challenges the dogma that all medical students are raised with that no new connections or pathways can emerge in the adult brain. That was news 10 or 15 years ago. Now it's widely accepted." I’m not sure what he means here; in other words, is it trauma that reorganizes the brain this quickly, or does this happen as a matter of course? I assume the latter. But regardless, the extreme example of phantom limb may reveal something fundamental about not only our brains, but their relation to our limbs and perhaps by extension (no pun intended) our prostheses.

3. What I am interested in, here, is the possibility – or perhaps the likelihood – that our almost constant interaction with technologies like “smart” cell phones and laptops may also remap the brain in nontrivial ways.

I found a lot of anecdotal data on phantom vibrations, phantom ring, vibranxiety. Right around 2006 and 2007 several articles in the popular press began to notice a trend in cell phone users. When Web developer Steven Garrity wrote about it in his blog, he got over 30 responders also citing the phantom sensations. (See the USA Today article at http://www.usatoday.com/news/health/2007-06-12-cellphones_N.htm. A Guardian article at approximately the same time comments on the similar nature of the phantom “hearing” of your cell phone’s ringtone. Obviously we are surrounded by cell phones with similar tones, but it turns out some of the sound issue has to do with our ears: “Certain sound registers - about 1,000 and 6,000 Hertz - are more easily caught by the human ear, and therefore more likely to stimulate a response.” And the term phantom ring is defined at UrbanDictionary.com, more or less as a common annoyance.

One theory behind both the phantom ring and phantom vibration is that its origins are physical: nerve damage, for example, or muscle memory. Another set of theories focus on psychological factors; the cell phone represents/creates a psychological need in us, a need to be connected. (Hence the preponderance of articles that describe the feeling as anxiety, though I don’t experience it that way, and I don’t imagine others all do, either). A third theory has to do with how we “learn” to perceive important new signals in our environment. Jeffrey Janata, director of the behavioral medicine program at University Hospitals in Cleveland, calls it "hypothesis-guided search." We are learning to pick out sensations of our phone vibrating, and this “leads you to over-incorporate non-vibratory sensations and attribute them to the idea that you're receiving a phone call." Alejandro Lleras argues that we set what he calls perceptual filters, and this setting is imperfect. His calling such phenomenon “false alarms” made me think of times lately when I thought I heard m name being called in a noisy environment (a café, a public square). I also remember my cousin Kevin listening to his new Beatles album on headphones back in 1975; when John sings the lines “she’s so……heavaaay,” he heard “she’s so…..KEVIN!” This happens three times in the song, and the third time he grew alarmed, jumped up (it was late at night), opened his attic bedroom door, and proceeded to fall down a very steep set of stairs. And then his mother and grandmother really DID call his name!

The connection I am wondering about, the one that Ramachandran is exploring with his work in the neuroscience of phantom limb pain, is neuroplasticity. This is what Doctors Janata and Ramachandran argue: the brain is able to form new connections in response to changes in the environment. Not surprisingly, the metaphor Janata uses is “wired,” as in the brain becomes wired to the regular sensation of the cell phone vibrating. He goes on to say that "Neurological connections that have been used or formed by the sensation of vibrating are easily activated. They're over-solidified, and similar sensations are incorporated into that template. They become a habit of the brain."

So if the brain can remap itself, create templates/filters (another metaphor) that then become habitual, the phantom vibration might lead to other discoveries about the ways we interact with, and adjust to, continual use of a whole panoply of gadgets and mundane prostheses. The cybernetic organism here would be one in which Kate Hayle’s notion of embodied knowledge is accurate; we incorporate our phones and laptops, and this incorporation is literally embodied in the brain’s neuroplastic response. Not only is the cell phone not simply a tool we use; it may be an example of a wide range of shifts in the human brain generated by the increasingly intimate connection of humans and postwar machines.