I Can See the Importance In Your Eyes
Jenny Galvao

According to research by Robert Ariel and Alan Castel of the Georgia Institute of Technology and the University of California, we have a very particular ways to encode information that we consider to be important, versus information that we feel is of a lower value.

Specifically, when we fixate on words, our pupils dilate more when the words we’re viewing are highly valued, and in turn, we experience a less significant dilation in pupil size when fixating on words of a lower value. Not only this, but we have a greater recall for the words labelled as important.

“Participants fixated equally on words regardless of their value, which indicates that participants did not strategically ignore studying low-valued words. Thus, differential resource allocation contributed to value-directed remembering, but information reduction did not,” the researchers point out.

In this experiment, participants had their pupil diameters recorded as they studied lists of words, which consisted of concrete monosyllable nouns with five letters. They were instructed that the list of words they’d be studying had point values (varying from 1 to 12) and they would be earning the corresponding point(s) for each word they could recall.

With the goal being to get as many points as possible, the words with high point values had a sense of importance in comparison to the words worth a lower amount of points. When the word “RECALL” appeared on the screen, the participants had to verbally recite as many of the words as they could remember from the list of 12. Each word was shown separately from the others, with an associated points value beside it. Participants had the same amount of time to study each individual word before being asked to recall them.

Low-value words (1-4 points) were recalled less often than the medium-value (5-8 points) and the high-value words (9-12 points). The measureable difference in pupil diameter showed that the greater allocation of resources to commit high-value words to memory is reflected in the greater dilation of the pupils.

When we’re given a goal, we want to succeed and meet that goal. In order to do so, we often need to make sacrifices, and pre-determine how we’re going to allocate our resources in the manner that will better complete the goal. Pupil dilation is just one of the many ways that we encode information and fixate on the target.

It would be irrational and frankly a waste of our limited cognitive capacities if we made an attempt to study all words equally as hard, knowing that the higher-value words will get us closer to our goal. We use this information to map out our movements, which are literally reflected in our eyes, as our nonverbal communication system is once again a tell-all.

Jenny Galvao_smallAbout the Author: Jenny Galvao is an undergraduate student at the University of Guelph studying psychology.





Ariel, Robert; and Alan D. Castel. Eyes wide open: enhanced pupil dilation when selectively studying important information. Journal of Experimental Brain Research. 2013. 232:337-344. DOI: 10.1007/s00221-013-3744-5