Making the Right Call

Why do you think the NFL was interested in a program like this? Why now?

In the past decade or so, officiating of NFL games has changed significantly. There are sophisticated video replay programs, but they slow the game and affect the momentum. You also lose the human element when you rely on technology too much. The officials are very important; there's a lot of symbolism, history, routine and respect. Nobody wants to change that. But since these technologies do exist, it's important to ensure that officials are as precise and accurate as possible. We're there to educate them on the science of vision. When you learn the neuro-ophthalmic principles behind factors impacting vision during critical moments, it helps you remember what to do and what not to do. They actually already know a lot of this stuff; we're just providing them with the correct vocabulary to discuss it and formalize it.

What neuro-ophthalmic principles do you focus on? What part of vision can officials control?

First, there's the visual field, which is your side vision. Your visual field will increase if you move away from something and decrease as you get closer. Although being closer improves resolution and acuity, you could miss important things going on to your side. You must balance visual acuity—how close you need to be to something—against the visual field. For example, when a snap is made from the center to the quarterback to start the play, it's critical for the game official to see the action around the ball since that interaction is the first point of contact and it's where a lot of infractions can occur. But once the play begins and there's been no false start or other penalty, referees must drop back at least five steps so they can see the whole field. Another principle is called dynamic visual acuity. When you move, your vision degrades. Whether you're moving your head or running, movement makes it harder to keep your eye on a target. If you have a clear line of sight and full visual field, you don't need to run, even when the play unfolds over some distance. It turns out, when it comes to accuracy of calls, it's better if you just stay where you are and follow the action with your head.

Very interesting! What other principles are involved?

The last thing we've been working with them on is eye movement. Referees must constantly decide where to focus. They watch something, decide if it's legal or not, then move their eyes to the next likely point of contact or potential penalty. That rapid movement—to get the center vision to a new target—is called a saccade. When following a moving target along with the eyes, that's called pursuit. Pursuit is a smooth movement. Referees must saccade in a certain sequence and prioritize where to look. If a receiver is catching the ball on the sideline, they have to look at the feet first to make sure the player is in bounds, then saccade to the arms to determine if the ball was caught. When a play starts, the official must look at the football when it's snapped to the quarterback, then saccade to the running back if the quarterback hands it off. If it's a fake handoff, the official has to saccade back to the quarterback who is now looking to throw. However, if the running back gets the ball and runs with it, that's pursuit. There are different saccadic prioritization and pursuit strategies, depending on whether it's a run or pass.

How is the training provided?

There are camps every year for NFL employees, players, officials, trainers, managers, etc. We go to the camp and train the people who train the referees. We present a lecture on the basics of neuro-ophthalmology, and then run through extensive videos. They're very visually oriented so we show them where the breakdowns occur in both good and bad calls. For the good, we show how the referee was in the right place or had the right saccadic prioritization. For the bad, we point out if the line of sight was obstructed, if adequate visual field wasn't maintained, if the official was running when he didn't really need to be running or if the official was looking at the wrong place when the critical play happened. We're explaining why their eyes need to move in a certain way and providing them with a science-based vocabulary they can put in their training manual, so that everyone speaks the same language.

What's next for the program?

In July of 2023, we published our first paper on the project in the Journal of Neuro-Ophthalmology, with solid academic metrics. We plan to follow along with the referees that have been trained in this method to see if they're making more accurate calls. We are asking participants to self-rate their confidence in using terms like saccade, pursuit, dynamic visual acuity, field of vision, etc. We know from these surveys that they enjoyed the training and learning that occurred. They do feel more confident. Assuming the NFL finds value in it, the next phase would be to show whether that learning translated into improved performance and accuracy in the field.