Silmäkaikkinen

Silmäkaikkinen is a Finnish term that translates to "eyeball echo" or "visual echo" in English. It describes a phenomenon where a person experiences a fleeting, ghostly image or sensation of something that is no longer there, often after it has moved out of their direct line of sight. This is commonly experienced with moving objects, such as a car passing by or a person walking across a room. The brain is, in essence, continuing to process the visual information for a fraction of a second after the stimulus has ceased.

This phenomenon is a normal perceptual artifact and not indicative of any underlying medical condition. It is thought to be related to the persistence of vision, a concept that has been studied for centuries. When light stimulates the retina, the neural signals continue for a short period even after the light source is removed. Silmäkaikkinen is a subjective experience of this post-stimulus neural activity. It can be more pronounced in certain lighting conditions or when the moving object is particularly bright or distinctive. While the exact neural mechanisms are still under investigation, it is understood to be a natural function of the visual processing system.