Improving Vision

Understanding visual development and recovery after head injuries

Joellen Leonen, clinical research lab manager, assesses an infant study participant in the Vision Development and Oculomotor Lab. 

MANY PEOPLE don’t know that when babies are born, they don’t see well. In fact, it takes months for the average infant to see colors and begin recognizing faces. For the first 12 months of life, their vision, perception, and coordination change rapidly, passing important milestones that help them take in the world around them.

But sometimes a child doesn’t follow that trajectory, and it’s often not obvious that something has gone awry until well into their critical learning years, leaving them at a significant disadvantage. 

That’s what Tawna Roberts, OD, PhD, associate professor of pediatrics and ophthalmology, is trying to head off in her research at Stanford. Her Vision Development and Oculomotor Lab studies several under-researched areas that intersect with the eye and brain, including early vision development and amblyopia (sometimes called “lazy eye”) in children, and traumatic brain injuries (TBI), like concussions, in adolescents and adults. 

One element that brings these two together is binocular vision—the ability to get both eyes to work together. Roberts’ goal is to solve a key problem in eye medicine: the lack of clinical evidence to guide personalized treatments for these conditions. 

“Clinicians don’t have the highest level of evidence for every patient care decision,” Roberts said. “Being able to push forward this research as a clinician-scientist and contribute to that body of evidence has been really satisfying.”

Roberts’ team knows first-hand the impact such research and treatments can have, especially on young people. 

Gayathri Srinivasan, OD, MS, clinical associate professor at the Byers Eye Institute, often comes back to a special case when she recalls why she wanted to work with the Vision Development and Oculomotor Lab, where she could add to such research and offer treatment to children and those struggling after a brain injury. 

Early in her career, Srinivasan treated a young boy, whose mother said always seemed to look through her rather than at her. A free eye exam and a glasses prescription later, she received a photo of the boy wearing his glasses and smiling. His mother's note read, “This was the first time he actually saw me and smiled at me.”

Srinivasan often thinks of that child, as he highlights the importance of the kind of work that she and other clinician-scientists do for children and families, she says. 

“It was such a touching moment for all of us and underscored the importance of vision in overall child development,” Srinivasan said.

Current studies

Today the lab is conducting research on vision development and adaptations in infants and preschoolers, as well as the effects of concussions on the visual system in adolescents and adults. The group is seeking participants for those studies, in which people can get an eye exam free of charge and a thank-you gift for their time. 

What Roberts and her team have found so far is that some symptoms that concussion patients suffer, such as dizziness and brain fog, both affect and are affected by a person’s visual system.

“These kids often have a lot of headaches and other symptoms that override the visual system,” Roberts said. 

A key part of the research is tracking the “natural history” of the improvement, stagnation, or decline of each patient’s visual system during early development or following a brain injury. 

When it comes to concussions, for instance, she and her team of researchers track patients’ progress as close to the time of the injury as possible and then observe which patients heal on their own and which patients need intervention to get back to a good baseline.

“This way, we can start to clinically home in on the patients who really need our help,” Roberts said.

Roberts has also received funding from the U.S. Department of Defense to study how to rapidly repair soldiers’ vision and prepare them to re-enter combat. Many soldiers who fought in the Iraq War suffered TBIs, and studying how these soldiers’ eyes react to visual stimuli can help identify crucial gaps in their care, Roberts says.

Dr. Tawna Roberts holds an infant study participant.

A Look at Disparities

Roberts' team will also explore health disparities and barriers to access to eye care, including how politics, geography, and economic inequality impact patients.


Not all states require vision screenings for school-aged children, so some may be quietly suffering a visual impairment that can disrupt their ability to learn. When a student is screened, a family may struggle to afford follow-up exams, a circumstance that tends to be more prevalent among lower-income families and racial minorities.


“We want to study those kinds of disparities to make a case for revamping social systems to help people from all backgrounds get the eye care they need,” Srinivasan said. “We see these disparities in the clinic, but we need more research to understand the barriers in access to eye care services for children.” 

Sonya is a freelance writer for the Byers Eye Institute at Stanford.