The brain represents the illusion of optics as a deferred reality

A study on humans and monkeys published in JNeurosci found the same subset of neurons coding for illusory complex flow motions. This discovery confirms, at the level of individual neurons, what the Czech scientist Jan Purkinje had supposed 150 years ago: "Illusions contain a visual truth".

The Pinna-Brelstaff figure is a static image of rings that seem to turn clockwise as one moves forward and in the opposite direction as one moves away from the figure. After previously identifying parts of the human brain representing Pinna's illusion, Junxiang Luo and colleagues at the Institute of Neuroscience of the Chinese Academy of Sciences first confirmed that the Rhesus macaque men probably perceived the illusion in the same way as people. The researchers then recorded the activity of individual neurons in previously identified brain regions and discovered cells signaling illusory motion in the same manner as the actual motion. A delay of about 15 milliseconds allows the brain to record the illusory movement as it was real. This study provides new insights into how the brain struggles with the constant shift between perception and reality.

Provided by
Society of Neurosciences