{"id":702,"date":"2014-05-02T13:17:51","date_gmt":"2014-05-02T21:17:51","guid":{"rendered":"http:\/\/www.kylemathewson.com\/?p=702"},"modified":"2014-05-02T13:17:51","modified_gmt":"2014-05-02T21:17:51","slug":"702-2","status":"publish","type":"post","link":"https:\/\/sites.psych.ualberta.ca\/kylemathewson\/702-2\/","title":{"rendered":"CONTROLLING BRAIN WAVES TO IMPROVE VISION"},"content":{"rendered":"

http:\/\/beckman.illinois.edu\/news\/2014\/04\/brain-waves-improve-vision<\/a><\/p>\n

Have you ever accidentally missed a red light or a stop sign? Or have you\u00a0 heard someone mention a visible event that you passed by but totally missed seeing?<\/p>\n

\u201cWhen we have different things competing for our attention, we can only be aware of so much of what we see,\u201d said Kyle Mathewson, Beckman Institute Postdoctoral Fellow. \u201cFor example, when you\u2019re driving, you might really be concentrating on obeying traffic signals.\u201d<\/p>\n

But say there\u2019s an unexpected event: an emergency vehicle, a pedestrian, or an animal running into the road\u2014will you actually see the unexpected, or will you be so focused on your initial task that you don\u2019t notice?<\/p>\n

\u201cIn the car, we may see something so brief or so faint, while we\u2019re paying attention to something else, that the event won\u2019t come into our awareness,\u201d says Mathewson. \u201cIf you present this scenario hundreds of times to someone, sometimes they will see the unexpected event, and sometimes they won\u2019t because their brain is in a different preparation state.\u201d<\/p>\n

\"\"By using a novel technique to test brain waves, Mathewson and colleagues are discovering how the brain processes external stimuli that do and don\u2019t reach our awareness. A paper about their results, \u201cDynamics of Alpha Control: Preparatory Suppression of Posterior Alpha Oscillations by Frontal Modulators Revealed with Combined EEG and Event-related Optical Signal,\u201d published this month in the\u00a0Journal of Cognitive Neuroscience<\/a>, reveals how alpha waves, typically thought of as your brain\u2019s electrical activity while it\u2019s at rest, can actually influence what we see or don’t see.<\/p>\n

The researchers used both electroencephalography (EEG) and the event-related optical signal (EROS), developed in the Cognitive Neuroimaging Laboratory of Gabriele Gratton and Monica Fabiani, professors of psychology and members of the Beckman Institute\u2019s Cognitive Neuroscience Group, and authors of the study.<\/p>\n

While EEG records the electrical activity along the scalp, EROS uses infrared light passed through optical fibers to measure changes in optical properties in the active areas of the cerebral cortex. Because of the hard skull between the EEG sensors and the brain, it can be difficult to find exactly WHERE signals are produced. EROS, which examines how light is scattered, can noninvasively pinpoint activity within the brain.<\/p>\n

\u201cEROS is based on near-infrared light,\u201d explained Fabiani and Gratton via email. \u201cIt exploits the fact that when neurons are active, they swell a little, becoming slightly more transparent to light: this allows us to determine when a particular part of the cortex is processing information, as well as where the activity occurs.\u201d<\/p>\n

This allowed the researchers to not only measure activity in the brain, but also allowed them to map where the alpha oscillations were originating. Their discovery: the alpha waves are produced in the cuneus, located in the part of the brain that processes visual information.<\/p>\n