It’s All in Your Head: Our Brains Know More Than We Think.

It's watching you.

What if I told you that you’re being watched?  That every decision you make is under constant observation and judgment.  That every action is catalogued, and every mistake identified… before it even occurs. Sounds creepy, right?  Like some sort of evil Orwellian plot from the future.  But we’re talking about science, not science-fiction, and the future-seeing, decision-judging voyeurs in this story are our own brains.  Lucky for us, they’re on our side.

Scientists have long understood that the messages that travel between brain and body are fast.  They have to be.  Without rapid signals to relay our mind’s intentions to our muscles, we’d never be able to swat a fly, slam on the brakes, or walk across a balance beam.

Visual and auditory clues allow us to continually refine our movements to stay on task: we see the fly move to the left, and our hand moves accordingly (though not always as fast as we would like). While these micro-adjustments depend on feedback from the senses, there are occasions when we need to act faster than our eyes and ears can supply clues.

It’s possible for concert pianists, for example, to strike multiple keys per second for sustained periods of time: each hand playing the correct notes, simultaneously. So, how do they know that they’re playing the right notes, and that these notes are at the right tempo?  The answer seems obvious: the pianists hear the music they’ve played and adjust either their pace or their finger placement on the keys accordingly.  Right?   Well, actually… no.

Even if their ears are covered and the music is silenced, pianists are still able to get it right: noise or no noise- it makes almost no difference in performance.  A successful piano recital, as it turns out, does not depend on auditory feedback. How is this possible? (This is like saying we don’t actually need to see the fly in order to know where to swat.)  Do musicians rely solely on memory, or do they have some type of mistake-tracking extra sense that the rest of us lack?

To answer these questions, researchers at the University of Sussex challenged the musical and motor skills of ten expert pianists. They wanted to determine the precise moment a pianist’s brain knew when a mistake had been made.  The idea was simple: if the researchers could determine when the brain registered an error, they’d be able to deduce the clues pianists use to correct their movements.

Now, short of dipping their fingers in molasses, it’s difficult to get a trained pianist to make a mistake- but the researchers did their best.  The subjects were given 20 minutes to listen to new music, and after a bit of time to practice, instructed to reproduce the music as fast as possible. From memory.  Blindfolded. With 60 electrodes pasted to their scalps.

It’s not hard to understand why the pianists occasionally struck a false note. However, researchers were surprised to find that incorrect keys were pressed more softly than keys corresponding to the correct notes.  It’s almost as if the pianists knew when they were about to hit the wrong keys, and slowed their fingers to lessen the impact of the mistake.

Well, actually… it’s exactly as if.  Researchers noticed that a specific spike of brain activity was associated with incorrect key presses- but that’s not the weird part.  This spike occurred before a wrong key was actually depressed.* So, the pianists’ brains were able to foresee upcoming mistakes (mistakes that the pianist hadn’t made yet!), and nearly curb them before they happened.  (Isn’t it nice to know that our brains are looking out for us?)

It’s likely that this ability to modulate rapid movements without clues from the senses is an evolutionary throwback: fast reflexes come in handy when you’re trying to hunt a woolly mammoth (or evade a lion).

But, does this mean musicians can see the future?  I don’t know- you might have to ask their brains.

*(I know what you’re thinking, but don’t worry, the researchers controlled for incorrect key presses caused by doubt rather than error-monitoring. Trust me, you don’t want me to get into all of that.)

The research described in this blog post was published in PloS ONE: (at the Public library of Science, you can read articles for free!)

Nobody is Perfect: ERP Effects Prior to Performance Erros in Musicians Indicate Fast Monitoring Processes

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~ by Meghan on April 24, 2009.

3 Responses to “It’s All in Your Head: Our Brains Know More Than We Think.”

  1. Neat! Brains are crazy. You should read that New Yorker article about itch and sensory perception. It talks about how much of our sensory perception is really the brain’s best guess at what is going on. (The gross part is really brief, I promise!)

    http://www.newyorker.com/reporting/2008/06/30/080630fa_fact_gawande?currentPage=all

  2. Very interesting! And I know I’ve done that sort of thing while doing science experiments, and as a kid playing the violin.

  3. Emily, she itched all the way through TO HER BRAIN. That’s all I need to know. (Just kidding, I did read it- it was morbidly fascinating)

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