Genetics plays a strong role in how people explore the environment visually, says a study that tracked the eye movement of twins.
“People recognise that gaze is important,” said Daniel Kennedy, Assistant Professor at Indiana University Bloomington College of Arts and Sciences in the US.
“Our eyes are moving constantly, roughly three times per second. We are always seeking out information and actively engaged with our environment, and ultimately where you look affects your development,” Kennedy said.
The researchers compared the eye movements of 466 children — 233 pairs of twins (119 identical and 114 fraternal) — between ages 9 and 14 as each child looked at 80 snapshots of scenes people might encounter in daily life, half of which included people.
Using an eye tracker, the researchers then measured the sequence of eye movements in both space and time as each child looked at the scene.
Published in the journal Current Biology, the study found a strong similarity in gaze patterns within sets of identical twins, who tended to look at the same features of a scene in the same order.
It found a weaker but still pronounced similarity between fraternal twins.
This suggests a strong genetic component to the way individuals visually explore their environments.
The more robust similarity in the eye movements of identical twins is likely due to their shared genetic makeup, the researchers said.
The researchers also found that they could reliably identify a twin with their sibling from among a pool of unrelated individuals based on their shared gaze patterns — a novel method they termed “gaze fingerprinting.”
“Eye movements allow individuals to obtain specific information from a space that is vast and largely unconstrained. It’s through this selection process that we end up shaping our visual experiences,” Kennedy said.