The Berkeley-based Minerva Foundation named vision researcher Frederick Miles the winner of its sixteenth annual Golden Brain Award for pioneering work that illuminated how the eyes and the brain work together to steady our view as we move.
Imagine that you are in your car heading for a tollbooth on the highway. As you come closer and closer to the tollbooth, your eyes are automatically, imperceptibly making ultra-rapid adjustments to help you stabilize your view. Your brain is busy too, orchestrating this response.
Miles, senior research physiologist at the Laboratory of Sensorimotor Research, National Eye Institute, National Institutes of Health, in Bethesda, MD, has studied our eye movements and vision in such situations for over 30 years.
"Fred Miles' work helps to explain how the brain guides our eye movements as we move about our complex visual environment," said the late Elwin Marg, executive director of the Minerva Foundation. "His research demonstrates that the mechanism we use to deal with the extraordinary complexity of the visual world and to avoid problems when viewing changing distances is extremely sophisticated - far more sophisticated than had previously been suspected. His research is also unique in that it draws upon extensive knowledge in two fields that are rarely blended - visual sensory and motor control."
Miles discussed his research in a seminar on "Population Coding of Vergence Eye Movement in the MST Area of Cortex," on January 17th, 2000 at the University of California, Berkeley, where he received his award.
Miles and his colleagues were the first to show that our brain is capable of responding much more rapidly than had been previously suspected and does so without us having to think about it. These automatic, machine-like adjustments begin to occur in only seven or eight hundredths of a second, which is two to three times faster than voluntary eye movements, and can deal with diverse visual challenges such as we might encounter when driving, jogging, or playing softball.
More recent work, with colleagues here and in Tsukuba, Japan, provides a dramatic example of sensorimotor coordination in the brain. The research was carried out on monkeys, which have eye movements very similar to ours. The team in Japan had evidence implying that a small region of the cerebral cortex known as the medial superior temporal (MST) area was involved in generating automatic eye movements. Together with Miles, the researchers recorded the activity of neurons in MST. Their work indicates that the individual cells in MST each encodes some restricted aspect of the sensory events that take place when we move toward or away from an object. Their unexpected finding was that the aggregate activity of the cell population in MST provides a complete description of the animal's motor responses (eye movements), including even the idiosyncratic differences between individual animals. The brain is, thus, conveying information in the activity of a population of cells in the same way that we communicate using sentences made up of individual letters and words. This finding was another small step to understanding the language of the brain.
Miles' work provides insights that may help clinical researchers someday develop ways to correct misalignments of the eyes, which affect two to five percent of the people in the world and severely impair their ability to visualize things in depth. Miles also worked to collaborate with clinicians to study the eye movements of children who develop strabismus (squint), a condition in which the two eyes are misaligned due to an imbalance of the eye muscles, to learn more about their motor responses and what goes wrong with their vision over time.