The prevailing purpose of blinking is to lubricate the eyeballs, to remove dust and other foreign particles from the eyeballs and to protect the eyes. Additionally, research conducted in 2012 by a group of Japanese scientists claims that blinking helps people focus on the world more efficiently.
On average, a person blinks 15 to 20 times per minute. The most common reasoning behind blinking is that it is done to protect and lubricate the eyeballs. However, the number of blinks needed per minute to do so is far less than the number of times people actually blink.
So in an attempt to find out why people blink so many times, a group of Japanese scientists used functional magnetic resonance imaging, or fMRI, to identify the areas of the brain that showed any activity during blinking. Their findings were published as a paper, named "Blink-related momentary activation of the default mode network while viewing videos," in the "Proceedings of the National Academy of Sciences" in December 2012.
Their research showed that during blinking, the areas of the brain that showed a spike in their activities were areas that were related to the default mode network in the brain. During blinking, the human brain goes into a state known as "wakeful rest," allowing the brain to take a break momentarily and focus more efficiently when the eyes are opened.