People in this career are better at seeing through optical illusions

A hint came from our previous work comparing mathematical and social scientists’ judgements of illusions (we work in universities, so we sometimes study our colleagues). Social scientists, such as psychologists, see illusions more strongly.

Researchers like us have to take many factors into account. Perhaps this makes us more sensitive to context even in the way we see things. But also, it could be that your visual style affects what you choose to study. One of us (Martin) went to university to study physics, but left with a psychology degree. As it happens, his illusion perception is much stronger than normal.

Training your illusion skills

Despite all these individual differences, researchers have always thought that you have no choice over whether you see the illusion. Our recent research challenges this idea.

Radiologists need to be able to rapidly spot important information in medical scans. Doing this often means they have to ignore surrounding detail.

Radiologists train extensively, so does this make them better at seeing through illusions? We found it does. We studied 44 radiologists, compared to over 100 psychology and medical students.

Below is one of our images. The orange circle on the left is 6% smaller than the one on the right. Most people in the study saw it as larger.

Here is another image. Most non-radiologists still saw the left one as bigger. Yet, it is 10% smaller. Most radiologists got this one right.

It was not until the difference was nearly 18%, as shown in the image below, that most non-radiologists saw through the illusion.

Radiologists are not entirely immune to the illusion, but are much less susceptible. We also looked at radiologists just beginning training. Their illusion perception was no better than normal. It seems radiologists’ superior perception is a result of their extensive training.

According to current theories of expertise, this shouldn’t happen. Becoming an expert in chess, for example, makes you better at chess but not anything else. But our findings suggest that becoming an expert in medical image analysis also makes you better at seeing through some optical illusions.

There is plenty left to find out. Perhaps the most intriguing possibility is that training on optical illusions can improve radiologists’ skills at their own work.

So, how can you learn to see through illusions? Simple. Just five years of medical school, then seven more of radiology training and this skill can be yours too.

Martin Doherty, Associate Professor in Psychology, University of East Anglia and Radoslaw Wincza, Lecturer in Behavioural Sciences, University of Central Lancashire. This article is republished from The Conversation under a Creative Commons license. Read the original article.