I love listening to music and watching dance. Although I enjoy these artistic performances, I am not an accomplished musician or even a competent dancer. Not surprisingly when expert musicians and dancers perceive these performances, they hear and see them differently than poor novices like me. But it isn’t just in their ears and eyes. Experts perceive using the action planning part of the brain – most likely through mirror neurons.
As a cognitive psychologist, I’ve always known that experts see and understand the world differently than novices. They process and remember information in their area of expertise more efficiently and effectively. Maybe you’ve noticed this based on personal experience. For example, I learned to play the guitar as an adult. For the record, I’m not very good, but I have fun making noise. But even with my rather limited ability, I found that after I learned to play, I started hearing music differently. I could hear and recognize chord progressions. In addition, I could sometimes even get a sense of what the guitarist was doing when playing a piece of music. My small amount of expertise changed my perception.
But what actually changed about my cognitive system? Had my ears changed; had my auditory perception neural mechanisms changed? Probably. But perhaps my perceptual system was also recruiting my action system even when I was simply listening to music. My brain may have been playing along.
Have you ever watched musicians when they listen to music? Sometimes they do more than simply nod their heads and tap their feet. They may start moving their hands as if they are actually playing the song.
I’ve often had the opportunity to watch ballet dancers as they watch other dancers or listen to a set of moves they are being asked to perform in class. Those ballet dancers aren’t still. Instead, they make small versions of the movements with their feet and hands as they prepare to perform the moves themselves.
But even when completely still, even when their feet and hands aren’t moving, the motor control parts of musicians and dancers’ brains are very busy. We know that perception is important for guiding action. But here’s the cool part: Action and movement planning guide perception as well.
Let’s start with dance. Calvo-Merino and colleagues (2005) put professional ballet and capoeira dancers (and some non-dancing control individuals) into an fMRI brain scanner. Then the researchers showed the dancers videos of both ballet and capoeira dance movements. Both sets of movements involved male dancers doing spins, kicks, and leaps. Calvo-Merino et al. found differences in brain activation when the dancers watched movements from their own style of dance compared to when they watched similar movements from the other dance style. When the dancers watched movement from their own areas of expertise, the areas of their brains associated with planning and making movements were substantially more active. The dancers perceived by activating the movement planning and control portions of their brains. Although their feet were still, their brains were dancing.
As with watching dance, listening to music also works through the motor control parts of the brain. Lahar and colleagues (2007) trained pianists to play a new piece of music. Then Lahar et al. put the pianists into an fMRI brain scanner to investigate brain activity when the pianists listened to the newly learned piece, to a novel piece of music, and to a familiar piece that they did not know how to play. With the piece they could play, the pianists activated not only the auditory perception areas of the brain but also the action preparation parts of the brain. With the other music, the activation was more focused on the auditory perception areas.
More recently, my colleague KJ Jantzen and his student Lawrence Behmer (Behmer & Jantzen, 2011) reported that even simply looking at sheet music activates motor planning in musicians but not non-musicians. Clearly experts perceive by invoking action plans.
All of this research is focused on a critical idea in neuroscience – mirror neurons. Mirror neurons, first discovered through research with non-human primates, fire both when individuals perform an action and when they observe someone else perform the action! The motor planning parts of the brain become active in humans both when performing an action and when perceiving the action. In other words, acting and perceiving probably involve the same mirror neurons. The brains of experts are dancing and making music even when they are simply sitting in the audience.
At one time psychologists assumed a linear flow of information. Perception leads to recognition, then to planning and thinking, which in turn leads to action. From the modern perspective of mirror neurons, action guides both perception and thinking. The ability to perform actions changes one’s perception. Experts see the world differently in part because they perceive using their ability to perform.