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Unconscious and uncelebrated activity of the basal ganglia

Dec 6, 2014

Spanish version

As I make my way through the day, most of my actions are thanks to the basal ganglia. Soon after I wake, I lean my body forward, and move a foot off the bed and onto the floor, while the palms of my hands press against the mattress and balance my body so I don't fall over. Now I swing the other foot to the floor, and now I'm standing.  Many body movements with little thought thanks to the basal ganglia.

The basal ganglia already learned the right routines through lots of daily practice, trial and error.  Now they direct my movements so that I fill my stovetop espresso maker with water and ground coffee.  I'm lucky my basal ganglia are at work, because other parts of my uncaffeinated brain are still in a fog.  I have my coffee, wash the cup, wash myself, get dressed, and out the door. Without my basal ganglia, I'd have to consciously think through each step of these routines.

While the basal ganglia are doing all this work, my cerebral cortex is thinking in words, planning ahead, consciously envisioning goals, evaluating priorities. Like executives in the top floor of the company, the cerebral cortex gets credit for the basal ganglia's work. Why do we so undervalue the activities of the basal ganglia and other parts of the brain operating outside our awareness? That's just it. We're not very aware of the operations occurring outside our awareness. And so we underestimate their contribution to our lives.

Sometimes, we become aware of these hidden activities. You return a difficult tennis shot, one that you couldn't have returned a year earlier. How did you pull that off? You're not quite sure.  A painter applies a brush stroke at a particular angle, beautifully executed. The basal ganglia learned their art through many thousands of past experiences.  They improved through trial and error without requiring conscious supervision from language regions of the brain.  "How did I do that?" you wonder.  You're not sure. That's because the parts of the brain responsible for the action aren't the brain areas now wondering about it.