Pacific students are breaking new ground with study on seeing underwater
Last year, Ashley Stanton and Diane Shafer, Pacific University seniors at the time, took on an exciting research opportunity, guided by Pacific University professors Dr. Brian Searcy and Dr. Brian Jackson. Little did they know, the study would extend a year past their graduation and would be on track to be considered for publication—a huge deal for these students and the five other undergrads helping with the project. The Pacific Index caught up with Stanton, who is now leading the study, to learn about this exciting research and how it could change how we see the world.
In 2003, a team of researchers from Lund University in Sweden discovered that a group of ocean- and island-dwelling people off the West coast of Thailand called the Moken have the ability, at least as children, to see almost twice as much detail underwater compared to untrained European children in the same environment. The researchers published a second article in 2006 detailing their success in training children in Sweden to reach the same level of visual acuity underwater after 11 training sessions. Now, Stanton’s team is looking to replicate the Swedish team’s results in an older age group—college students—in a study titled “The Effects of Environmental Training on Visual Acuity and Pupil Size on College Students.”
Stanton’s research focuses on college students because children’s minds and bodies are malleable and adaptive in many ways that adults’ aren’t. College students fall in the sweet spot between childhood and middle age when presbyopia, or the hardening of the eye’s lens, sets in.
What makes the ability to see underwater special? Stanton explained: “You can see underwater with goggles because you have that air pocket.” She continued, “When you’re underwater, the refraction of water and your eye are practically the same, so you’re not able to bend light like you can out in the open. Your lens has to do more work to bend that light, and so we’re training to see if we can force the lens to accommodate.” (Lens accommodation is when the eye changes the lens’s shape to change focal length, or optical power.)
The initial question in the Swedish research was whether the adaptation was something evolved or learned; it could have been either, since the Moken people have been freediving for food in that environment for many generations.
The researchers tested several possible mechanisms by which the children were achieving such high visual acuity. They identified lens accommodation and pupil constriction as two primary mechanisms employed by the Moken children when diving without goggles. Pupil constriction typically occurs in bright conditions, while pupils dilate underwater due to low light conditions. The fact that the Moken children constricted their pupils suggests they did so to increase depth of field and decrease scattered light, sharpening the image blurred by refraction. While this may be a reflex paired with lens accommodation, Stanton and her team are doing the same trainings using air and low-light conditions as well, to see if they can improve visual acuity in the dark.
Stanton said there were two big hurdles for the project, especially starting it during COVID. The first was building the testing apparatus. The Stoller Center has a dunk tank, but due to COVID policies, they had to drain the tank after every use—a major obstacle when each participant has to be tested 11 times with 24 to 72 hour intervals. “It was fun to think, ‘Okay, well how can we do this?’ How can we get their faces in the water while keeping it COVID safe, and we had to deal with leaky buckets, and how do we fix that in the middle of data collection?” Stanton recalled. She continued, “So in the least scientific terms possible, it is a trash can. It is literally a white trash can that we have wrapped dimmable lights around so we can adjust the light level. We cut out the bottom, put Plexiglass in and then we slide the stimulus underneath. There’s also a headband that they rest their head on to keep them at a certain distance.” They built two apparatuses, one with just air and one with water—partly to control for refraction, but also to look at the potential for training higher acuity in low light.
The other major obstacle was finding enough participants. “That’s not due to Pacific’s population. It’s not that they don’t want to help. Our project is a big ask. We need them to come in 11 separate times. That’s a lot, and they also have to come back between 24 and 72 hours after the previous appointment. That’s a huge ask because we have a lot of athletes and really dedicated people here,” Stanton explained. The potential participant pool was further reduced by the requirement of having uncorrected 20/20 vision to control that variable.
With a total of 14 participants, Stanton’s team is finishing up their third round of data collection now, and will be analyzing the data and writing it up for publication in the spring. Originally, Stanton had planned to be done with the project last spring, but after analyzing the first set of data and presenting the findings at conferences, Stanton and her professors realized they could actually submit the study for publication if they had more data.
When asked how her research was received at the Murdoch conference in November, Stanton recalled, “My speech didn’t necessarily fit in, per se, because there are lots of bird and turtle studies and really interesting work in the life sciences, which is where I presented, but typically you don’t work on humans.” Murdoch may be expanding their presence in kinesiology in the future, and Pacific will be hosting the Murdoch conference next year.
If Stanton’s team is able to train young adults to increase their visual acuity underwater, the training program could be implemented to help anybody who works or recreates underwater, including military personnel. If they are able to train visual acuity in low-light conditions, nighttime drivers would benefit immensely.
Stanton said that Dr. Searcy is interested in extending this research to 40 and 50 year olds to see if they can delay the onset of presbyopia. For now, though, the excitement of potential publication is big news for Stanton and her fellow undergraduates. — Lane Johnson