27 July 2005

Thinking Stops When You Blink

Do you notice the world around you when you are blinking your eyes?

A group of scientists just found out that blinking suppressed brain activity in the visual cortex and other areas of the brain. Brain activity is usually activated when people become conscious of visual events or objects in the outside world.
Parts of the brain are temporarily "switched off" when we blink, scientists have found.

The team from University College London found the brain shut down parts of the visual system for each blink.

Writing in Current Biology, they said this was the case even if light was still entering the eyes.

The researchers said this could explain why people do not notice their own blinking, as it gave us an "uninterrupted view of the world".

A blink lasts for between 100 and 150 milliseconds. We automatically blink 10 to 15 times a minute to moisten and oxygenate the cornea.

During a blink, there is no visual input and no light, but we do not consciously recognise everything has momentarily gone dark.

[ BBC News Health, Jul 25 2005 ]

In connection with this, I have also observed that people blink their eyes more rapidly when trying to analyze a problem, like solving an algebraic equation, or simply recalling a past memory. I wonder what happens to the brain during moments like this. Is eye-blinking also a manifestation of "re-booting," much like what happens when you push the reset button on your personal computer?

I hope more studies on eye-blinking are done especially on how it relates to the thinking process.

4 reactions:

watson said...

Come to think of it, we only think about blinking when we try not to blink (usually on a dare). In which case the eyes get irritated. This is interesting ... I thought we blink to solely moisten the eyes and since it happens so fast, I thought of it as merely reflex.

Doc, isn't it that when a person blinks too often, it is a sign that he is sick with something? Or a vitamin deficiency?

Dr. Emer said...

You must be talking about motor tics, Watson. The most commonly referred medical term for that is Tourette Syndrome.

Duke said...

yesterday I was in a ferry and this little girl started to stare at me and out of the blue I found myself playing the do-not-blink game... I felt exhausted after and the little girl won ! :) I guess I need to reboot my brain more often than her :)

Dr. Emer said...

The do-not-blink game dries up your eyes and your patience. I've played that game many times when I was a kid, too. 'Hard to beat kids, they're very good at it. :)