Scientists discover why it doesn’t go dark when you blink
People blink on average every five seconds, but despite no light falling on our retinas we still see a stable picture of the world.
Neuroscientists have now identified an area of the brain that plays a crucial role in perceptual memory as the reason why blinking does not disrupt our view.
Experts from the German Primate Centre and the University Medical Centre Gottingen made the discovery while studying epilepsy patients.
Alongside colleagues from the US, they noted how people see the world as a stable, unified whole despite blinking.
The concluded it must be possible for the brain to retain visual information for a short period of time and use it to create a conclusive image without interruptions.
Dr Caspar Schwiedrzik’s team of neuroscientists investigated the medial prefrontal cortex, a part of the brain crucial for short-term memory and decision making
Scientists at New York University examined how it worked in patients with epilepsy.
One treatment method involved temporarily implanting electrodes in the brain while the subjects were asked to perform a visual task examining their perceptual cortex.
In one of the subjects, a section of her superior frontal gyrus had been removed due to illness, meaning she was unable to store the visual information in the tests.
“Our research shows that the medial prefrontal cortex calibrates current visual information with previously obtained information, and thus enables us to perceive the world with more stability, even when we briefly close our eyes to blink,” said Dr Schwiedrzik.
They added that this was not only true for blinking, but also for higher cognitive functions: “Even when we see a facial expression, this information influences the perception of the expression on the next face that we look at.
“We were able to show that the prefrontal cortex plays an important role in perception and in context-dependent behaviour,” Dr Schwiedrzik said.
The study is published in the journal Current Biology.