Nav: Home

Surprise discovery in the blink of an eye

August 23, 2016

We probably do it every day, but scientists have only just discovered a distinct new way in which we move our eyes.

The team from the University of Tübingen in Germany assessed the eye movements of 11 subjects using tiny wires attached to the cornea and with infrared video tracking. In results published in eLife, they discovered a new type of eye movement that is synchronised with blinking.

The movement they discovered helps to reset the eye after it twists when viewing a rotating object. It is like avoiding tiny rotations of a camera to stabilise the image we perceive. We don't notice the eye resetting in this way because it happens automatically when we blink.

"We were really surprised to discover this new type of eye movement and it was not what we had anticipated from the experiment," says lead author Mohammad Khazali.

"We had expected to find that another, already well-known type of eye movement is synchronized to blinking."

Although it is brief, blinking creates an interruption in our visual perception. We spend up to a tenth of our waking hours blinking but hardly notice it. It serves an essential role in lubricating the eye and may even provide the brain with small, frequent mental breaks.

The scientists sought to investigate whether a reflexive, involuntary eye movement called torsional optokinetic nystagmus (tOKN) occurs at the same time as blinking. The theory was that this reflex also creates a break in the visual system so synchronising them minimises downtime.

The subjects' eye movements were tracked as they viewed a rotating pattern of dots. As their eyes twisted to follow the dots, they frequently reset, via tOKN, to avoid moving beyond the mechanical limits of the eye muscles. However, this resetting was imperfect and the eyes gradually twisted until the muscles couldn't twist any more. This varied between subjects from three to eight degrees of rotation.

Once they reached their maximum, the eyes reset so they were no longer twisted at all. This happened at the same time as blinking. The scientists have called this newly-discovered movement blink-associated resetting movement (BARM).

"The eye's sharpest vision is enabled by a spot on the light-sensitive sheet of the retina called the fovea and this needs to stay balanced to ensure objects of interest can be scrutinised in an optimum way," says Khazali.

The frequency and size of the movement is determined by how far the eyes have deviated from a neutral position. It helps to reduce strain in the eyes as they move to assess the world around us. In further experiments, the scientists discovered that it even occurs when the eye is not tracking a rotating object.

"To discover such a ubiquitous phenomenon in such a well-studied part of the human body was astonishing to us and we're very grateful to the volunteers who took part in the study," says Khazali.
-end-
Reference

The paper 'A new motor synergy that serves the needs of oculomotor and eye lid systems while keeping the downtime of vision minimal' can be freely accessed online at http://dx.doi.org/10.7554/eLife.16290 . Contents, including text, figures, and data, are free to reuse under a CC BY 4.0 license.

About eLife

eLife is a unique collaboration between the funders and practitioners of research to improve the way important research is selected, presented, and shared. eLife publishes outstanding works across the life sciences and biomedicine -- from basic biological research to applied, translational, and clinical studies. All papers are selected by active scientists in the research community. Decisions and responses are agreed by the reviewers and consolidated by the Reviewing Editor into a single, clear set of instructions for authors, removing the need for laborious cycles of revision and allowing authors to publish their findings quickly. eLife is supported by the Howard Hughes Medical Institute, the Max Planck Society, and the Wellcome Trust. Learn more at elifesciences.org.

eLife

Related Eye Movement Articles:

Study uses eye movement test to confirm brain ageing effects
A new study, published in PeerJ, shows how University of Liverpool researchers have used a newly developed eye movement test to improve the understanding of how parts of the brain work.
The mysterious movement of water molecules
Water is all around us and essential for life. Nevertheless, research into its behaviour at the atomic level -- above all how it interacts with surfaces -- is thin on the ground.
Zebrafish study reveals developmental mechanisms of eye movement
Zebrafish research is a promising way to understand the neural and genetic causes of eye movement problems in people, according to multi-university research led by Albert Pan of the Fralin Biomedical Research Institute at VTC.
Antibody-based eye drops show promise for treating dry eye disease
Researchers have identified the presence of a specific type of antibody, called anti-citrullinated protein autoantibodies, or ACPAs, in human tear fluid.
Do as i say: Translating language into movement
Researchers at Carnegie Mellon University have developed a computer model that can translate text describing physical movements directly into simple computer-generated animations, a first step toward someday generating movies directly from scripts.
Left eye? Right eye? American robins have preference when looking at decoy eggs
Just as humans are usually left- or right-handed, other species sometimes prefer one appendage, or eye, over the other.
Climate driving new right whale movement
New research connects recent changes in the movement of North Atlantic right whales to decreased food availability and rising temperatures in Gulf of Maine's deep waters.
Movement impairments in autism could be reversible
Researchers from Cardiff University have established a link between a genetic mutation and developmental movement impairments in autism.
Gut bacteria may control movement
A new study puts a fresh spin on what it means to 'go with your gut.' The findings, published in Nature, suggest that gut bacteria may control movement in fruit flies and identify the neurons involved in this response.
Increased electrical activity in eye may relieve short-term dry eye pain
A boost of electrical activity in the eye's mucous membranes may lead to new treatments for the painful condition known as dry eye.
More Eye Movement News and Eye Movement Current Events

Trending Science News

Current Coronavirus (COVID-19) News

Top Science Podcasts

We have hand picked the top science podcasts of 2020.
Now Playing: TED Radio Hour

Listen Again: Meditations on Loneliness
Original broadcast date: April 24, 2020. We're a social species now living in isolation. But loneliness was a problem well before this era of social distancing. This hour, TED speakers explore how we can live and make peace with loneliness. Guests on the show include author and illustrator Jonny Sun, psychologist Susan Pinker, architect Grace Kim, and writer Suleika Jaouad.
Now Playing: Science for the People

#565 The Great Wide Indoors
We're all spending a bit more time indoors this summer than we probably figured. But did you ever stop to think about why the places we live and work as designed the way they are? And how they could be designed better? We're talking with Emily Anthes about her new book "The Great Indoors: The Surprising Science of how Buildings Shape our Behavior, Health and Happiness".
Now Playing: Radiolab

The Third. A TED Talk.
Jad gives a TED talk about his life as a journalist and how Radiolab has evolved over the years. Here's how TED described it:How do you end a story? Host of Radiolab Jad Abumrad tells how his search for an answer led him home to the mountains of Tennessee, where he met an unexpected teacher: Dolly Parton.Jad Nicholas Abumrad is a Lebanese-American radio host, composer and producer. He is the founder of the syndicated public radio program Radiolab, which is broadcast on over 600 radio stations nationwide and is downloaded more than 120 million times a year as a podcast. He also created More Perfect, a podcast that tells the stories behind the Supreme Court's most famous decisions. And most recently, Dolly Parton's America, a nine-episode podcast exploring the life and times of the iconic country music star. Abumrad has received three Peabody Awards and was named a MacArthur Fellow in 2011.