Moral decisions can be manipulated by eye tracking

Moral decisions can be manipulated by eye tracking
Research from University College London shows that moral decisions can be manipulated by monitoring eye gaze. Credit: Daniel Richardson

Moral decisions can be influenced by tracking moment to moment movements of the eyes during deliberation, finds new research from Lund University, Sweden, University College London and University of California Merced.

Many of the choices we face in daily life have a character, from deciding whether to give money to a homeless person asking for change to separating out recyclables from the trash.

"People often assume that their moral opinions are stable preferences that already exist in their hearts and minds," says Michael Spivey from the University of California, Merced, "but we hypothesized that many of your may arise 'on the fly' as a result of how you look at and interact with your environment."

Using a novel experimental paradigm, the researchers used remote eye-trackers to monitor participants' gaze while they thought about complex moral questions such as, 'Is murder sometimes justifiable?'. The participants were presented with two alternatives to each question, and were asked to consider which those they considered to be morally right. Although they were completely unaware of it, participants' eye movements were determining when they were told to make their decision. For each trial, a target alternative was randomly selected, and once the eye tracker registered that the the participants had looked at the target for a certain amount of time, they were asked to make their decision immediately. The results showed that the participants' moral decisions were systematically biased towards the target. Overall, they choose the randomly selected alternative as their own moral opinion in 58% of trials, rather than 50% without the manipulation.

"What we find in this study is that the precise timing of our decisions can be a powerful influence on the choices that we end up making. The process of arriving at a moral decision is not only reflected in people's eye gaze but can also be determined by it," Philip Pärnamets, one of the authors from the University of Lund, explains.

The participants were influenced without being presented different arguments or information; instead, the paradigm exploits the fact that where people look reveals their moment-by-moment thought processes. This suggests, says Pärnamets, that the process of arriving at a moral decision is intertwined with process of looking at the world, and more generally, that peoples' decision processes are reflected in their eye gaze.

Moral decisions can be manipulated by eye tracking
Graphical abstract of a University College London experiment showing that moral decisions can be manipulated using eye tracking. Credit: Daniel Richardson

"In other words, the same interplay between the brain the hand and the eye that plays out when we reach for a cup of coffee, is also involved in reasoning if something is morally right or wrong," says Daniel Richardson, one of the authors of the study from University College London.

The study is the first to demonstrate causal links between and gaze and moral choices, but builds on previous work on how gaze is reflected in simple choices, like those between foodstuffs. Daniel Richardson explains: "Scientists already knew that when we look back and forth between two items on a menu, for example, our gaze patterns reveal what we might choose. Our main contribution is to show that by controlling exactly when someone makes a decision, we can influence what they decide"

"Today, all sorts of sensors are being built into mobile phones," says Petter Johansson from the University of Lund and one of the authors, "and they are even able to track . Simply by monitoring small changes in our behaviour, these devices have the potential to aid our decisions in ways that have not been possible before."

Explore further

New studies show moral judgments quicker, more extreme than practical ones—but also flexible

More information: Biasing moral decisions by exploiting the dynamics of eye gaze, PNAS,
Citation: Moral decisions can be manipulated by eye tracking (2015, March 16) retrieved 19 August 2019 from
This document is subject to copyright. Apart from any fair dealing for the purpose of private study or research, no part may be reproduced without the written permission. The content is provided for information purposes only.

Feedback to editors

User comments

Mar 17, 2015
Who thinks these things up? Sounds like Svengali has been reincarnated somehow.

Mar 17, 2015
It makes sense that the participants were biased toward the choice that they had just been looking at (the paper itself confirms that this is what happens, rather than some left/right bias).

If I have a decision between two choices in a setup like this, I'll read one, try to justify it in my mind, and then read the other, try to justify it, go back to the first one and try to justify it again, etc. until I am convinced that one is more justifiable. If interrupted while looking at one, I will be focused on it, and also be in the middle of justifying it in my mind, so it seems reasonable that I would be biased toward picking it.

The same principle is used in trials - in legal systems where the benefit of the doubt is supposed to go to the defense, the defense gets to present the final arguments.

Apr 01, 2015
The 3-second timeframe was imposed to keep the subjects from gaming the experiment rather than to properly model moral decision-making.

The study begins by stating: "Moral cognition arises from the interplay between emotion and reason.." I don't see that 3 seconds allows a person's feeling brain to connect with their thinking brain to produce emotionally informed yet reasoned successive responses to a 98-question battery.

If the study's results really support the finding that "..moral choices are no different.." then deciding whether "One should never intentionally harm another person" is no different than a "top of the head" answer to "Is Denmark larger than Sweden?"


Please sign in to add a comment. Registration is free, and takes less than a minute. Read more