advertisement
Home » News » Brain Seems to Work on 15-Second Delay

Brain Seems to Work on 15-Second Delay

Brain Seems to Work on 15-Second Delay New research finds the brain uses a delay mechanism that can blind us to subtle changes in movies and in the real world.

In the study, published in the journal Nature Neuroscience, University of California, Berkeley scientists discovered a “continuity field” in which the brain visually merges similar objects seen within a 15-second time frame.

Unlike in the movies, where in “Pretty Woman,” Julia Roberts’ croissant inexplicably morphs into a pancake, objects in the real world don’t spontaneously change, so the continuity field stabilizes what we see over time.

“The continuity field smoothes what would otherwise be a jittery perception of object features over time,” said David Whitney, Ph.D., senior author of the study.

“Essentially, it pulls together physically but not radically different objects to appear more similar to each other,” Whitney added.

“This is surprising because it means the visual system sacrifices accuracy for the sake of the continuous, stable perception of objects.”

Conversely, without a continuity field, we may be hypersensitive to every visual fluctuation triggered by shadows, movement, and a myriad of other factors. For example, faces and objects would appear to morph from moment to moment in an effect similar to being on hallucinogenic drugs, researchers said.

“The brain has learned that the real world usually doesn’t change suddenly, and it applies that knowledge to make our visual experience more consistent from one moment to the next,” said Jason Fischer, Ph.D., lead author of the study.

To establish the existence of a continuity field, the researchers had study participants view a series of bars, or gratings, on a computer screen. The gratings appeared at random angles once every five seconds.

Participants were instructed to adjust the angle of a white bar so that it matched the angle of each grating they just viewed. They repeated this task with hundreds of gratings positioned at different angles. The researchers found that instead of precisely matching the orientation of the grating, participants averaged out the angle of the three most recently viewed gratings.

“Even though the sequence of images was random, participants’ perception of any given image was biased strongly toward the past several images that came before it,” said Fischer, who called this phenomenon “perceptual serial dependence.”

In another experiment, researchers set the gratings far apart on the computer screen, and found that the participants did not merge together the angles when the objects were far apart. This suggests that the objects must be close together for the continuity effect to work.

Source: University of California, Berkeley

 
Abstract of brain photo by shutterstock.

Brain Seems to Work on 15-Second Delay

Rick Nauert PhD

Rick Nauert, PhDDr. Rick Nauert has over 25 years experience in clinical, administrative and academic healthcare. He is currently an associate professor for Rocky Mountain University of Health Professionals doctoral program in health promotion and wellness. Dr. Nauert began his career as a clinical physical therapist and served as a regional manager for a publicly traded multidisciplinary rehabilitation agency for 12 years. He has masters degrees in health-fitness management and healthcare administration and a doctoral degree from The University of Texas at Austin focused on health care informatics, health administration, health education and health policy. His research efforts included the area of telehealth with a specialty in disease management.

APA Reference
Nauert PhD, R. (2015). Brain Seems to Work on 15-Second Delay. Psych Central. Retrieved on August 17, 2018, from https://psychcentral.com/news/2014/03/31/brain-seems-to-work-on-15-second-delay/67891.html

 

Scientifically Reviewed
Last updated: 6 Oct 2015
Last reviewed: By John M. Grohol, Psy.D. on 6 Oct 2015
Published on PsychCentral.com. All rights reserved.