According to a new study, these vital organs can work like time machines to process constant visual stimuli.
Although the brain is an extraordinary organ on which the functioning of our bodies depends, it also needs time to update itself, according to new research from UC Berkeley.
Scientists revealed that, just like social media, our brains constantly upload rich visual stimuli. But instead of seeing the latest images in real time, we actually see older versions because these organs require an update time of more than 10 seconds.
The study also addressed the mechanism behind the 'continuity field', a function of perception in which our brains fuse what we constantly see to give us a sense of visual stability.
"If our brains were always updating in real time, the world would be a hectic place with constant fluctuations of shadow, light and movement , and we would have the feeling of being hallucinating all the time," David Whitney, lead author of the work and professor of psychology, neuroscience and vision sciences at UC Berkeley.
Like a time machine
To avoid the situation described by the expert, our brain works like a time machine that constantly takes us back in time to stabilize the constant visual stimulation it receives. This mechanism is also known as visual dimming.
“Our brain is like a time machine. It keeps sending us back in time. It's like we have an app that consolidates our visual input every 15 seconds into a single impression so we can handle everyday life," said Mauro Manassi, study leader and assistant professor of psychology at Scotland's University of Aberdeen and a former postdoctoral researcher at Whitney's lab at UC Berkeley.
Following a study in which 100 people were examined for the underlying mechanism of change blindness - in which we are unaware of subtle changes that occur over time, such as the difference between actors and their stunt doubles -, the results suggested that the brain works with a slight delay when processing visual stimuli, and this has both positive and negative implications.
Processing the images
The positive is that the delay helps prevent us from feeling bombarded by visual information in everyday life . However, when precision is needed, such as during surgery, we may miss important details.
The scientists highlighted that change blindness also reveals how the continuity field is an intentional function of consciousness and what it means to be human.
“We are not literally blind,” Whitney concluded. “It's just that our visual system's slowness to update itself can make us blind to immediate changes because it clings to our first impressions and drags us back into the past. Ultimately, however, the field of continuity supports our experience of a stable world."
“It's too much work to constantly update the images, so (the brain) hangs on to the past because the past is a good predictor of the present. We recycle the information of the past because it is faster, more efficient and requires less work”
— David Whitney, professor of psychology, neuroscience and vision sciences at UC Berkeley
Fifteen
seconds is the maximum time it takes for our brain to “update”.
See the illusion created by the researchers to demonstrate the visual smoothing mechanism:
Interview
Mauro Manassi Associate Professor of Psychology at the Scottish University of Aberdeen and former Postdoctoral Fellow in the Whitney Lab at UC Berkeley.
Q: Why did you decide to study how our brain loads visual stimuli?
- The main question is: why do things look the way they do? More specifically: at all times our eyes are moving, our head is moving, we are moving, and the world around us is constantly moving. Also, objects are constantly darkened, blurred, etc. However, we do not experience any of this, we constantly perceive a fairly stable world. In a way, we are in a constant illusion of stability, which our brain creates. Hence we were interested in discovering how the brain creates this illusion.
Q: You also compare our brain to social media.
- Instead of analyzing each of the visual information snapshots, the brain groups the information over time (in a span of 15 seconds). More specifically, our brain "softens" perceptual interpretations over time. For our visual system, it is definitely a better strategy to “average” what we see over time, rather than analyzing every moment (which would be very messy, time consuming, energy consuming, etc.). To use a metaphor, our brain does not analyze every moment of our perceptual experience, but rather, like social media, “updates” itself from time to time. This does not mean that we live 15 seconds in the past (as some media reports), but rather that what we see now is biased back up to 15 seconds.
Q: What happens in our brain during the 15 seconds that the update lasts?
- Our brain constantly applies this type of "smoothing" over time. This means that what we see now, in the present, is influenced by the objects presented 15 seconds ago.
Q: What problems could this delay cause?
- Could be relevant to radiologists. In radiology reviews, radiologists scan sequences of X-rays to look for tumors. If our view is constantly biased towards the past, your judgments about a current X-ray could be biased towards the previous one. For example, if there is no tumor on the previous x-ray, and there is a tumor on the current x-ray, radiologists might not see it on the current x-ray because they are biased towards the past. We have research showing that radiologists show this type of effect, and we're working on ways to avoid it.
0 Comments:
Post a Comment
Your comment and facebook share will be appreciated