Intrigued by research with mice showing that exercise excited parts of the brain associated with vision, researchers at the University of California in Santa Barbara decided to find out if exercise could improve the vision of humans. A UC Santa Barbara news release reports that the researchers gave 18 volunteers a wireless heart rate monitor and an EEG (electroencephalogram) cap containing 64 scalp electrodes. While on a stationary bicycle, the volunteers performed a simple orientation discrimination task using high-contrast stimuli composed of alternating black and white bars presented at one of nine spatial orientations. The same tasks were performed while at rest and during bouts of both low- and high-intensity exercise. Next, the scientists fed the recorded brain data into a computational model that estimated the responses of the neurons in the visual cortex activated by the visual stimuli. They analyzed the responses while participants were at rest and then during low- and high-intensity exercise. What did they find? “We found that the peak response is enhanced during low-intensity exercise relative to rest and high-intensity exercise,” said researcher Tom Bullock. “We also found that the curve narrows in, which suggests a reduction in bandwidth. Together, the increased gain and reduced bandwidth suggest that these neurons are becoming more sensitive to the stimuli presented during the low-intensity exercise condition relative to the other conditions.” In other words, brains work better during exercise, but only low intensity exercise.