How Fast Can We Recognize Food? 108 Milliseconds
You walk into a kitchen, open a cupboard and scan its contents — it may be something you do several times every day.
But what's happening in your brain when you're doing that scanning?
There's a lot going on, scientists say, and it's all happening extremely quickly.
Researchers from the University of Sydney did a test with 20 participants. They were asked to look at a number of images of foods and non-foods. While they did this, their brain activity was monitored using small sensors.
They found that signals sent to the brain include information about how natural, processed and calorific a food may be. And also that the brain can tell whether something is a food or a non-food, say a tin of beans or a teapot for example, after about 108 milliseconds.
The brain decides whether a food is natural — for example, a fruit or vegetable — within 400 milliseconds.
So why is this important?
Thomas Carlson, who was one of the researchers, said that they wanted to get a better understanding of the way that our brains visually perceive food.
The report found that our brains respond automatically to the perceived calorie count of the food and how natural it is, which suggests that these aspects are very important in the way we think about food.
"Vision is key for influence," said Carlson. "Visual cues often guide our food choices, such as when we're navigating a supermarket, looking at advertisements or seeing posts about food on social media."
This knowledge might help to encourage people to make healthier choices through smart advertising.
The team suggested that our brains are making rapid calculations about food even when we're not paying full attention.
However, they said that while our brains may be able to begin working out whether a food is edible or not after just 80 milliseconds, we probably have to be paying attention to take that information in.
