The 19th-century mathematician Joseph Fourier showed that two rhythms could be summed to produce a third rhythm. Stanford researchers have shown that such mathematics are at play in the brain activity that produces arm movements. (Click image to enlarge)
Neuroscientists had once believed that the neurons that control movement send specific external information such as distance, direction and velocity to the muscles of the body. In a surprising new finding, however, researchers at Stanford University have proposed a new model that says motor neurons instead send basic rhythmic patterns down the spine to drive movement. The neurons that control movement are not a predictable bunch. Scientists working to decode how such neurons convey information to muscles have been stymied when trying to establish a one-to-one relationship between a neuron's behavior and factors such as muscle activity or movement velocity. In an article published online June 3 by the journal Nature , a team of electrical engineers and neuroscientists working at Stanford University propose a new theory of the brain activity behind arm movements. Their theory is a significant departure from existing understanding and helps to explain, in relatively simple and elegant terms, some of the more perplexing aspects of the activity of neurons in the motor cortex. In their paper, electrical engineering Associate Professor Krishna Shenoy and post-doctoral researchers Mark Churchland, now a professor at Columbia, and John Cunningham of Cambridge University, now a professor at Washington University in St. Louis, have shown that the brain activity controlling arm movement does not encode external spatial information - such as direction, distance, and speed - but is instead rhythmic in nature.
TO READ THIS ARTICLE, CREATE YOUR ACCOUNT
And extend your reading, free of charge and with no commitment.
