RadioLab has a brilliant short podcast on the psychological role of blinks, based on a study that found that when watching a film our blinks are remarkably synchronised.
The programme dispels the myth that blinking serves only to keep our eyes wet as apparently studies have shown that we don’t blink any more or less in different humidities.
Instead, it explores a fascinating new study that found that blinks became synchronised when watching a film of another person, but not when watching landscapes or listening to stories.
Interestingly, blinks seems to be controlled so they occur at the start and end of meaning actions.
This is from the study abstract:
Synchronized blinks occurred during scenes that required less attention such as at the conclusion of an action, during the absence of the main character, during a long shot and during repeated presentations of a similar scene. In contrast, blink synchronization was not observed when subjects viewed a background video or when they listened to a story read aloud. The results suggest that humans share a mechanism for controlling the timing of blinks that searches for an implicit timing that is appropriate to minimize the chance of losing critical information while viewing a stream of visual events.
Blinking helps us comprehend the world. I find that quite amazing.
We know that blinking is also tied to some quite fundamental functions of the brain. For example, the higher the amount of spontaneous blinking you do, the higher the amount of dopamine you produce in the striatum, a deep brain area.
This is also links to your ability to stop unwanted actions, with a recent study linking higher blink rates to slower stop times.
As always the RadioLab programme is gripping audio velvet. I really recommend some headphones and 15 minutes of undisturbed time to lose yourself.