Monday, August 23, 2021

What happens when our eyes move?

Eyes may resemble still cameras or movie cameras, but it's probably more accurate to regard them as very active extensions of the brain. 


Unlike cameras, the eyes must contend with constantly changing input as images are jumping on the retinas. 

We move our eyes about three times per second. Each time we do, the image projected on the retinal surface shifts and resets. 


Although the process is mostly unconscious, we are always surveying the peripheral areas of the retina for where to jump next. 

Right before your focus shifts from one point to another, a message travels from the motor cortex to the eye muscles predicting the movement and anticipating the observed result. A process called corollary discharge suppresses the signal during the jump so that we're not overwhelmed with the smeared image.

Despite all this frenetic movement we maintain the impression that the world is stable.


franny said...

Which Rembrandt painting is this detail from?

franny said...

From which Rembrandt painting is this detail?

James Gurney said...

I believe it's called "Old Man in Military Costume" from the Getty Museum and it looks like a portrait of his father.

Evelyn said...

And the second jewel is in the Hispanic Society of America (in New York City) — which alsyowns a trove of Sorollas:

Evelyn said...

And the second jewel is in the Hispanic Society of America (NYC):

Susan Krzywicki said...

The more that we learn about how our brains/body work, the more fascinating it is. That idea that we are taking in different "snapshots" and making them into some sort of seamless experience could also be looked at as a metaphor: we build stories as we go. We make pieces into wholes.

S. Stipick said...

Have you read Anthony Waichulis's Compositional Primer? He goes into great detail talking about the how the eye functions and idea of verdical vision. He also spends some time citing the resources he derives his information from, should inquiring minds seek to follow and come to their own conclusions. I feel it would be great compliment to articles like this. Freely available on his website.

Roberto Quintana said...

@ Susan: I just finished reading Temple Grandin’s book: “Thinking in Pictures, my life with autism” in which she describes her autism induced visual thinking process, similar to what you describe.
@ James: Ms. Grandin writes in chapter 10, page 220: ”…Dr. Bruce Miller at the University of California provides hard evidence that primary visual thinking and musical parts of the brain are sometimes blocked by the frontal cortex. He studied patients with frontal-temporal lobe dementia (a type of Alzheimer’s). As the disease destroys language parts of the brain, art and music skills emerged in people who had no previous interest in art or music. As language deteriorated, the art became more photo-realistic… ” she says “The frontal cortex is connected to everything in the brain and it interferes with perceiving details.” -RQ