Laziness is contagious

Feeling lazy, impatient, or prudent? New research suggests it could be contagious, and you might have your friends, colleges and family to blame.

In research published in PLOS Computational Biology, a duo from the Brain and Spine Institute in Paris, France, found that people learn about these three traits from those around them, unconsciously adjusting their own attitudes to imitate those of others.

Using mathematical modelling, Marie Devaine and Jean Dauizeau analysed the responses of 56 participants to a series of decisions they made both before and after seeing the responses of others. Participants were led to believe that the decisions made by the “others” were real, when in fact they had been carefully crafted by the researchers.

The scientists operated under the premise that individuals change their beliefs after observing those of others. The evolutionary benefit of this imitative behaviour is that it facilitates fast learning; copying others means you don’t have to waste time discovering something already known.

The traits of prudence, impatience, and laziness are key in determining goal-directed behaviour. Prudence reflects high risk evaluation, impatience is associated with delay, and lazy people find that rewards aren’t worth the effort.

This led the researchers to ask: do we gather information on these traits from the responses of others? And do our own attitudes impact how we learn about the attitudes of others?

To find out, they first needed to create a mathematical model of the problem to test against their subjects. The model predicted that two phenomena arise when people learn about what other people think. 

First, a person will overestimate the amount to which their beliefs resemble those of others – a condition known as “false consensus” bias. Second, an individual will change their attitudes to match those of others – something called “social influence” bias.

Commenting on the significance of the duo’s approach, cognitive psychologist Jeroen van Boxtel from Monash University in Australia notes that “the model complexity is in the fact that the model, and humans, need to learn hidden – covert – attitudes, and observable – overt – behaviour, which is a multi-step process”.

But did the model hold true when compared to the responses of real-life subjects? In short, yes.

The researchers found that people become significantly more impatient, lazy or prudent after observing the behaviour of somebody more susceptible to these traits. Additionally, the mathematical structure was confirmed when they found that subjects guess the attitudes of others to be similar to their own.

They also found that people change their own positions to align with the attitudes of others once they discover what they are.

Van Boxtel indicates that the significance of the research lies in its ability to accurately predict the behaviour of humans from a model.

“It’s often relatively easy to come up with a model that explains past experimental data. However, the importance of a model is that they can make new predictions,” he says.