Optical illusion: Which orange circle is the bigger one in this brain teaser? 90% of people guess it wrong
In the latest optical illusion, viewers are shown a picture with two orange circles. Look at it for nine seconds and determine which one is bigger, and over 90 percent chose the wrong option.
The viral optical illusion showed two orange circles, and both were surrounded by grey circles, which leaves viewers convinced one is larger in size. Before scrolling down to see the image, close your eyes for five seconds.
Once you have opened your eyes, look at the image below for just nine seconds to spot the bigger circle.
Did you guess that the orange circle on the right was bigger, like 90 per cent of the population? Well, you are wrong! In reality, both orange circles are identical in size. Then why does one look bigger than the other?
The optical illusion, known as the Ebbinghaus illusion, demonstrates how our brain uses context to judge size: objects surrounded by smaller shapes seem larger, while those surrounded by bigger shapes appear smaller.
German psychologist Hermann Ebbinghaus discovered this optical illusion in the 19th century.
According to the Conversation report, the human visual system does not just measure what is in front of our eyes; it interprets shapes in relation to their surroundings. Psychologists say the ability helps humans make quick size and distance judgements in everyday life, but it can also lead people astray.
Research showed that factors like age, gender, neurodevelopmental conditions, and culture influence how strongly people experience the optical illusion.
Until recently, scientists thought there was no way to resist such illusions. However, a study that compared over 100 psychology and medical students to 44 experienced radiologists found otherwise, reported The Conversation.
Radiologists, trained to spot anomalies in medical scans while ignoring distractions, were much better at assessing the true sizes in Ebbinghaus-style images. Most non-experts needed an 18% size difference to 'see through' the trick, but radiologists could accurately judge circles with differences as small as 6 to 10%.
Interestingly, trainee radiologists did not show this advantage, indicating that the skill develops through years of professional practice.
A: Yes, they are identical, the size difference is an illusion caused by surrounding shapes.
A: The Ebbinghaus illusion, or Titchener circles.
A: Radiologists, people with autism or schizophrenia, and young children.
A: Yes, but it requires long-term practice, such as the visual training radiologists undergo.
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