Study expands on what happens in the blink of an eye

Adam Cohen-Nowak | Student Life

The average person will blink two to three times while reading this sentence and about 15 to 20 times in a minute. A new study conducted by researchers at Osaka University in Japan suggests that involuntary blinking affects perception and memory in ways previously unconsidered.

Ocular lubrication, the process by which people cleanse their eyes of debris and keep them from drying out, was thought by scientists for many years to be the sole function of the muscular reflex for blinking. But according to Marcus Raichle, a professor and researcher in the School of Medicine and an editor of the study, a lot more happens during a blink.

The study, published in the Proceedings of the Royal Society last November, found that involuntary blinking activates a network of brain areas called the “default mode network.”

Generally, the default mode network takes over when the brain isn’t focused on anything in particular, and is responsible for things like self-reflection. Meanwhile, the dorsal attention network takes over when one’s attention is focused on a goal-directed task such as reading or washing the dishes.

During a blink, researchers found that the brain switched to the default mode network for the 300-400 milliseconds that the eye is shut—meaning the default mode network may play a role even in active mental processes.

Participants in the study viewed videos, including clips from “Mr. Bean,” knowing they would answer questions about what they had just watched afterward. They were informed that their eye movements would be measured by a machine called a vertical electrooculogram. But they did not know that the focus of the experiment was their blinking.

According to the research, blinking activates certain brain areas and is also involved with an array of different functions, such episodic or self-referential memory, meaning the memory of personal experiences.

“What sort of stuck out to me [about this study] was how goal-directed behavior trades dominance with introspective and self-knowledge processes,” freshman Ted Little, a Philosophy-Neuroscience-Psychology major, said.

Dr. Tamami Nakano, a researcher at Osaka University and the author of the study, said the study may imply either of two things—that blinking enables people to “chunk” visual information, breaking it down for memory, or that it gives birth to a sort of “stream of consciousness”—a term coined by Williams James in the 19th century.

“There is no meaningless habitual action,” Nakano wrote in an email to Student Life. “Unintentional blinking dramatically and insidiously changes our brain state.”

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