Dance. Skip. Jump. Lick. As you read these words, your brain is working to help you understand what each word means.
Now, scientists have found that the same part of your brain that gets busy when you're actually dancing, skipping, jumping, or licking is also active when you silently read these action words.
The tissue in question is a strip that runs along the surface of your brain from one ear to the other. This strip is known as the motor cortex.
Scientists have long known that the motor cortex is responsible for controlling voluntary movement—any action you decide to do, such as kick, wave, or run. An involuntary movement is one you can't control, such as the beating of your heart.
A new set of brain scans, obtained by scientists at the Medical Research Council in England, shows that the motor cortex becomes active even when people just read action words.
In the experiment, when a person read the word "lick," the part of the motor cortex associated with movements of the tongue and mouth became active. An increased blood flow to that part of the brain signaled the activity. In another example, when a person read the word "jump," blood flow increased in the part of the motor cortex connected with leg movements.
The results suggest that the motor cortex is involved not just in performing an action but also in helping people understand the meaning of the word for a given action.
It's an unexpected finding because scientists had thought that a separate part of the brain processed language. It now appears that the brain has a more complicated way of interpreting words.
Whether you're dancing or just reading about dancing, your motor cortex puts on its dancing shoes!—S. McDonagh
Bower, Bruce. 2004. The brain's word act: Reading verbs revs up motor cortex areas. Science News 165(Feb. 7):83-84. Available at http://www.sciencenews.org/20040207/fob2.asp .