I've got an article in today's New York Times about one of my perennial fascinationsmusical hallucinations. One of the reasons that I find this condition so interesting is that it gives us a look under the neurological hood. Our brains do not simply take in objective impressions of the world. They are continually coming up with theories, and they test them against perceptions every moment of our waking lives. It would be impossible to test them against a complete picture of reality, because the world is simply too complex and ever-changing. Instead, the brain makes quick judgments on scraps of information, revising bad theories that don't make good predictions or using good theories as the basis for actions. Some scientists argue that musical hallucinations are evidence that our brains even make theories about music. When we hear stray sounds, we match them to tunes in our memory, in a sort of internal game of Name That Tune. Unfortunately, some people can't test their theories well enough, it seems, and so they wind up thinking a church choir is singing in the next room, when in fact there is only silence.
There's one line of evidence that supports this explanation of musical hallucinations that I didn't have room in the article to explore. It turns out that some people have an analogous problem with their vision. They suffer from a condition known as Charles Bonnet syndrome, in which they have visual hallucinations. In some cases, the hallucinations are nothing but textures or wallpaper-like patterns. In other cases, people may see a row of people floating in front of them. Reginald King, the elderly gentleman who described his musical hallucinations to me, also suffers from Charles Bonnet syndrome. He told me about how he would see patterns on the ceiling, or sometimes a cat or a dog running across his bed.
Victor Aziz, one of the scientists I interviewed for this story, has noticed that some other people also experience both visual and musical hallucinations, and doesn't think it's a coincidence. It's possible that regions of the brain that handle processing complex structures of both sound and sight can short-circuit in a similar way, producing similar hallucinations. And interestingly, brain scans of people with visual hallucinations are strikingly similar to those of people with musical hallucinations. In each case, the higher information-processing centers become active even when the regions that normally relay information from the senses are quiet. If we accept a theory of what we see, it's as real as the theories of what we hear.
Enjoyed the article in today's Times.
I had a passing fancy with visual hallucinations, given a review paper I presented at the American Academy of Neurology about a decade ago on peduncular hallucinosis (available at http://www.geocities.com/ahris2/lhermitte.html ). Those, like the ones you wrote about today, are fascinating aspects of what happens when things go awry!
-Anthony
neuropsychological.blogspot.com
Our brains do not simply take in objective impressions of the world. They are continually coming up with theories, and they test them against perceptions every moment of our waking lives.
I'd call them hypotheses (as opposed to theories) to remain consistent with the scientific terminology. We test hypotheses, and a collection of such tests supports a particular theorem.
We can probably all observe that phenomena briefly before the revised hypothese conforms with reality. For example when a spot on the floor for a fleeting moment looks like a bug or the car alarm that just started sounds like your own.
Now I wonder if déjà vu can be explained similarly as bad hypotheses?
I'd chime in with Torbjorn regarding deja vu. Its more of what we feed to our brains subconcious that really is taking precedence.
Very interesting! . . . I used to have musical hallucinations infrequently as a child; also, even less frequently, random individual words - hasn't happened since adolescence, if I'm remembering right. Wasn't deaf (unlike 1/3 of the folks discussed in the article), but I was also diagnosed with auditory processing disorder - maybe a connection?
It was definitely different from imagining music or getting a tune stuck in your head - I could clearly "hear" it, although it was somehow not the same kind of hearing as real music . . .
Reminds me of moving into a house that had a lot of spiders in the yard. No visiter ever failed to comment on their size and numbers.
The first night there, after midnight, I looked out into the yard and saw huge spiders coming across the field. Intellectually, I knew these were really random blackberry vines draped with long grass, but visually I saw spiders. Sitting up to 'enjoy' this free hallucination was interesting but a little scary.
I could have gone out with a flashlight to check, but- what if they really were spiders? Better to put my faith in the fact that such a thing had never happened before, so it probably wouldn't happen that night either.
Interesting. Anthony's article instilled a bit of fear. What could be wrong inside the brain if one experiences these hallucinations?
Between the ages of about 7 and 12 years, I had what is now called out of body experiences. They occurred infrequently, and usually in a room when other people were present. I could watch others and myself from a high corner in the room. Most fascinating aspect was that I could not smell anything, even if cooking was occurring nearby. Never told anybody, I feared the worst from my parents for being strange -- they wanted only a normal high achieving child.
These hallucinations suddenly stopped. After reading Anthony's article, I hope that whatever was wrong somehow corrected itself. I doubt the likelihood of this kind of healing, but then I am not going to worry about it either.
Hah! You folk don't know true genius when you see it. Musical "hallucinations" may be the sort of unwanted nutty stuff described in the article referring to people who can't stop the music in their heads and who actually think it's coming from outside their heads - But! musical "hallucinations" (what a term!) can also be the sign of a true genius, such as myself of course. (And I'm quite offended by all you doctors poking around my grey matter, get the fuck out and get some genius of your won.)
Being a musical genius (who alas has yet to profit from the experience, even in terms of fame), every so often when I'm really super-duper tired, I lie down in bed and allow the music to flow.
The kind of brilliant music that I hear is literally undescribable. It's beautiful enough to break your heart. There must be at least a hundred pieces to the orchestra and the sound that they produce through the blending of their individual crystalline talents is absolutely extraordinary.
Have I ever thought that it came from without my head? Come on -
Does it just "show up"? Nope. Only "shows up" a few times a year if I'm lucky and I have to have not slept for a good 48 hours or so.
Do I consider it an "imbalance" that needs to be "diagnosed" and "treated"? What the fuck's wrong with you guys? You have some blasé view of how human beings should be and anything beyond that is abnormal?
Holding the gift is music is something I'm grateful to god for (it's an expression, purists) and I'll defend it against the view that holds that we all oughtta move to some boring cardboard-cutout caricature of what real human beings are like.
That said, I love your blog and have read your Evolution book with profit. ;-)
mnuez:
I think you misunderstand. In his article and post Carl is trying to describe what is, not what should be. You got to listen to the music...
BTW, Carl, heard you on Fresh Air the other day. Well done, sir.
D
Oh, wow, man. Time was I went to some expense and effort in order to experience stuff like this...
Between the ages of about 7 and 12 years, I had what is now called out of body experiences. They occurred infrequently, and usually in a room when other people were present. I could watch others and myself from a high corner in the room. Most fascinating aspect was that I could not smell anything, even if cooking was occurring nearby. Never told anybody, I feared the worst from my parents for being strange -- they wanted only a normal high achieving child.
That's interesting!
Does this also apply in some form to people who are suffering from temporary brain damage, i.e. a cerebral hemorrhage, tumor removal, or would that be different phenomena? I have seen this with two people now. Each of them had phases of hallucinations, both sound and vision, and it was sheer impossible to convince both people that they were experiencing something irreal [None of them could remember these phases after recovery].
What is the reltionship between CBS and those individuals that experience multiple senses, such as tasing words or seeing letters in different colors? anyone?
Well I disagree with the Ipod theory for one reason. I do not own one and I have had so called "musical hallucinations" for 4 years now. It sometimes go's away for a day or so but mostly it is in my head. I had to learn to accept it cause their is no cure for it, that is if it is a disorder in my opinion. At times I really like the music there and then there is times I get frustrated so I just learn to accept it.