Nav: Home

How our brains integrate online reviews into our own product preferences

May 31, 2017

UCL researchers have identified how the human brain integrates social information when a person decides how much they like something, by studying how user reviews on Amazon influence how people rate the products.

The study, published in the Journal of Neuroscience and funded by Wellcome, found that people take into account not only a product's average rating, but also the number of reviews, as their brains factor in the reliability of social information.

"As online reviews are influencing more and more of our shopping choices, it's interesting to see that our brains process this information in a sophisticated manner," says the study's lead author, Dr Benedetto De Martino (UCL Institute of Cognitive Neuroscience).

For the study, 18 participants first looked at images and descriptions of products on Amazon, and rated the products and their own confidence in that rating. They were then presented with the products again, this time while in an fMRI scanner, but the descriptions were replaced with user reviews, including both the average rating and the number of reviewers as shown on actual Amazon listings.

After seeing the online reviews, participants' judgments were heavily influenced by the reviews and gave ratings that were in between their original rating and the average review score. Crucially, when products had a large number of reviewers, participants were more inclined to give ratings that lined up with the review score, particularly if they lacked confidence in their initial appraisals, while they were less influenced by ratings that came from a small number of reviewers. To make the experiment realistic, participants were incentivised as they knew they would be given one of the products that they rated highly.

When making judgements that were influenced by user reviews, the researchers saw that two adjacent brain areas that are used in social cognition, and to represent value, were most active. The way the participants updated their ratings was in line with a mathematical model of Bayesian integration, which has previously been demonstrated to capture many aspects of human perception.

"Our study was the first to show that our brains manage uncertainty by taking reliability into account when assessing how desirable something is, in a similar way to how our brains process simpler perceptual information," Dr De Martino said.

The participants differed in how much they conformed to the group consensus. In those individuals who stayed most true to their initial judgements, the scanner revealed there was more activity in one region of their brains, the dorsomedial prefrontal cortex, which has previously been shown to play a role in monitoring differences between a person's opinion and that of the group.

"Humans are innately social, so it makes sense that we are swayed by the opinions of the group. While there's value in sticking to your own beliefs, it can also be beneficial to take other people's opinions into account, and not over-value your own opinions," Dr De Martino said.

"An intriguing explanation for the activity in the dorsomedial prefrontal cortex is that it's used to represent and manipulate multiple beliefs, which adds to previous research finding that it's key to understanding the thoughts of others," said the study's senior author, Professor Brad Love (UCL Experimental Psychology and the Alan Turing Institute).
-end-


University College London

Related Amazon Articles:

Hydroelectric dams may jeopardize the Amazon's future
Hundreds of built and proposed hydroelectric dams may significantly harm life in and around the Amazon by trapping the flow of rich nutrients and modifying the climate from Central America to the Gulf of Mexico.
Amazon rainforest may be more resilient to deforestation than previously thought
Taking a fresh look at evidence from satellite data, and using the latest theories from complexity science, researchers at the University of Bristol have provided new evidence to show that the Amazon rainforest is not as fragile as previously thought.
The Earth sank twice, flooding the Western Amazon
A tiny shark tooth, part of a mantis shrimp and other microscopic marine organisms reveal that as the Andes mountains rose, the Western Amazon sank twice, each time for less than a million years.
Flammable floodplains are weak spot of Amazon forest
Peripheral parts of the Amazon forest were long thought to be most vulnerable to climate-induced collapse.
New eyeless, pale catfish from middle of Amazon named
A new species of blind, Amazonian catfish was named for the discoverer's young daughter, who frequently goes on trips to the field with him.
Vicious circle of drought and forest loss in the Amazon
Logging that happens today and potential future rainfall reductions in the Amazon could push the region into a vicious dieback circle.
Ancient peoples shaped the Amazon rainforest
We often think of the Amazon rainforest as a vast expanse of nature untouched by humans.
Ancient peoples shaped the Amazon rainforest
An international team of ecologists and social scientists has shown in a new study published March 3 in the journal Science that tree species domesticated and distributed throughout the Amazon basin by indigenous peoples before 1492 continue to play an important role in modern-day forests.
Plant dominance in the Amazon is shaped by past civilizations
Plants that were domesticated by pre-Columbian peoples are, to this day, much more likely to be dominant in Amazonian forests than other species, a new study reveals.
Mapping Biodiversity and Conservation Hotspots of the Amazon
Researchers have used remote sensing data to map out the functional diversity of the Peruvian Andes and Amazon basin, a technique that revealed hotspots for conservation.

Related Amazon Reading:

Best Science Podcasts 2019

We have hand picked the best science podcasts for 2019. Sit back and enjoy new science podcasts updated daily from your favorite science news services and scientists.
Now Playing: TED Radio Hour

Jumpstarting Creativity
Our greatest breakthroughs and triumphs have one thing in common: creativity. But how do you ignite it? And how do you rekindle it? This hour, TED speakers explore ideas on jumpstarting creativity. Guests include economist Tim Harford, producer Helen Marriage, artificial intelligence researcher Steve Engels, and behavioral scientist Marily Oppezzo.
Now Playing: Science for the People

#524 The Human Network
What does a network of humans look like and how does it work? How does information spread? How do decisions and opinions spread? What gets distorted as it moves through the network and why? This week we dig into the ins and outs of human networks with Matthew Jackson, Professor of Economics at Stanford University and author of the book "The Human Network: How Your Social Position Determines Your Power, Beliefs, and Behaviours".