The brain’s preparation state — whether it’s focused or unconscious — can have a significant impact on vision. A team of researchers from the Beckman Institute for Advanced Science and Technology at the University of Illinois at Urbana-Champaign and the City University of New York has found that alpha waves, which characterize the brain’s electrical activity while at rest, can influence vision. The team used event-related optical signals (EROS), which examine how light is scattered, as well as electroencephalography (EEG), to measure how the brain reacts to external stimuli. Image shows the position of each of the light sources (in red) and detectors (in yellow) through the EROS and EEG processes, as well as 3-D reconstruction of the estimated light path of each optical channel between a source and detector (in green). Courtesy of the University of Illinois Beckman Institute for Advanced Science and Technology. EROS, developed in the Cognitive Neuroimaging Laboratory of Gabriele Gratton and Monica Fabiani, psychology professors, members of the Beckman Institute's Cognitive Neuroscience Group and members of the research team, employs IR light that passes through optical fibers to measure changes in optical properties in the active areas of the cerebral cortex. It can noninvasively identify precisely where there is activity within the brain. “[EROS] exploits the fact that when neurons are active, they swell a little, becoming slightly more transparent to light,” Gratton and Fabiani said. “This allows us to determine when a particular part of the cortex is processing information, as well as where the activity occurs.” In addition, the researchers have been able to map where the alpha waves originate: The cuneus, which is located in the area of the brain that processes visual information. “Knowing where the waves originate means we can target that area specifically with electrical stimulation,” said Kyle Mathewson, a postdoctoral fellow at the Beckman Institute and one of the researchers. This could help drivers and pilots, athletes and equipment operators to be more aware of their surroundings, he said. Alpha waves can inhibit what is processed visually, which can make it difficult to see anything unexpected. However, when the conscious brain concentrates, it can halt the alpha waves and allow for more focused visualization. “We found that the same brain regions known to control our attention are involved in suppressing the alpha waves and improving our ability to detect hard-to-see targets,” said Diane Beck, a member of the Beckman Cognitive Neuroscience Group and one of the researchers. The study was funded by the Natural Sciences and Engineering Research Council of Canada, the Beckman Institute and the National Institute of Mental Health. The research is published in the Journal of Cognitive Neuroscience (doi: 10.1162/jocn_a_00637). For more information, visit: www.beckman.illinois.edu