Mind the Gap

I heard the Soup Dragons song "I'm Free" the other day, on a TV commercial (for the Gap). It's stuck in my head now. This Stones cover is really perfect for mass media -- bits of guitar and raggae and an energizing chorus. Seems kind of wild, but really pretty safe.

When was the last time you heard this song? I can't remember. For a while I thought it had been on ads pretty much continuously, and that I must have heard the song at least a few times in recent months. Upon reflection, however, I think it's been years and years (AT&T wireless used it a while back, I think).

I bring this up because we had a confabulating patient a while back. He had anterograde amnesia (he could not make new memories, kind of like the guy in Memento ). When you'd ask him what he'd been doing this morning, or yesterday, he'd make stuff up. Reasonable stuff, to be sure, delivered in a matter-of-fact way. But he could go into great detail of what he'd been watching on TV, or what he'd seen when he went for X-Rays -- even if the TV was off, and no X-Rays were taken.

There are two takes on this kind of confabulation in patients:

Barbara Wilson et al notes that confabulation tends to be an acute reaction to the loss of new memories. After some months or years, patients more freely admit they don't know what they've just been doing. But some story-telling seems to persist; she had a patient who insisted, every few minutes, that he just woke up. He couldn't be convinced otherwise, even when confronted with hard evidence. She compared it to the delusions of schizophrenic patients, as "an attempt to provide a rational and acceptable solution to strange and dramatic experiences." (In light of this, it's interesting to note that most amnesiacs do not report this waking sensation).

Whitlock observes that amnesiac confabulation cannot be a reaction to embarassment. He cites an old paper suggesting that confabulation occurs when patients forget that they can't remember (which was really a plot hole in Memento). Interviews suggest the patient believes what he or she is saying, and really can't evaluate the correctness of the narrative. They don't know what they're saying is wrong, and moreover, they don't know that they don't know.

Maybe the key to resolving these two takes on confabulation is measuring (through EEG, or fMRI, or through facial expression?) whether there's a flicker of fear or uncertainty before the amnesiac patient responds to a question. Then, I'd be more likely to believe the brain generates some kind of "rational and acceptable" solution to calm the patient and answer the question (though, to be clear, even in this case the patient can't recognize the falsehood).

More interestingly, I wonder if the brain's first response -- for all people -- is to make something up, and this gets edited a few moments later by the input of memories. In amnesiacs, that input never comes.

Would this explain why people sometimes start to answer a question, then abruptly stop? I've been party to several post-call pimpings on the wards, when I think I know something I truly don't. It takes a second before I realize that I had no idea what was about to come out of my mouth.

This phenomenon might also explain my Soup Dragons lapse. Until next time.