Lead researcher Professor Earl Miller and his associates at MIT’s Picower Institute for Learning and Memory base these findings on a study performed with monkeys trained to seek out a specific tilted colored bar on a sequence of bars displayed on a computer monitor. They monitored the neurons in three brain regions as the primates carried out their task and discovered that the activity shifted between the three regions in sequence and that the monkey’s attention shifted precisely in time with the changes in brain activity.
Prior to this study, scientists were unsure whether recognition occurred by looking at an entire scene at once and picking the desired image from the crowd or by another method such as this shifting which is reminiscent of the way a spotlight follows the action on stage. That said, this sort of activity shift makes a great deal of sense for visual processing. Many different areas of the brain are involved in this processing; a timed shift between areas prevents them all from firing at once which would likely overwhelm the brain and prevent the brain from correctly processing visual input. According to the Picower study, these shifts occur approximately 25 times per second.
The ebb and flow of neural activity – brain waves – have been studied for more than a century now, but their exact role in brain function remains somewhat murky. This study is the first that indicates brain waves may be tied directly to computational activity. It is currently unclear whether the brain waves act like an internal processing clock for all brain function or just for vision; much more research is needed before definitively deciding precisely how this timing works.
TFOT has previously reported on research into how computers can recognize specific objects in large scenes. TFOT has also reported on other aspects of visual processing including the development of an artificial eye that can integrate with the retina, the discovery of motion detection cells in the retina, and research into the visual processes of the Caenorhabditis elegans worm which could lead to advances in our understanding of human sight.
Read more about the Picower research on visual processing, brain waves, and the brain’s internal clock in this MIT news release.
Icon image credit: Jens Langner