A breakthrough study has discovered how ‘simultaneous contrast’ pictures trick your eyes
VISION
The illusion pictured here is playing tricks on your eyes. Despite initial appearances, the bar in the middle of the picture is actually just one shade of grey – it only appears lighter at one end due to the background gradient.
Such ‘simultaneous contrast’ illusions like this have long fascinated scientists, with many pondering why these pictures trip us up so easily. However, a breakthrough study from the University of Exeter may have unravelled the mystery: high-contrast optical illusions are caused by limitations in our eyes, rather than more complex neurological processes involving context and prior knowledge.
In simpler terms, your brain’s processing power is not to blame, but rather the ‘hardware’ of your visual system.
“This throws into the air a lot of long-held assumptions about how visual illusions work,” Dr Jolyon Troscianko, one author of the study published in PLOS Computational Biology, said.
As previously discovered, our eyes communicate with our brains by adjusting how fast the neurons in the brain fire. However, as Troscianko explained, “There’s a limit to how quickly neurons can fire and previous research failed to consider how this might impact our perception of colour.”
In the study, researchers created a computer model that mimicked the ‘limited bandwidth’ of the human eye, replicating the way we perceive visual information. When this model was exposed to ‘simultaneous contrast’ illusions, the researchers found that the model would become overwh
