this post was submitted on 24 Sep 2023
85 points (82.4% liked)
Asklemmy
43905 readers
1034 users here now
A loosely moderated place to ask open-ended questions
Search asklemmy ๐
If your post meets the following criteria, it's welcome here!
- Open-ended question
- Not offensive: at this point, we do not have the bandwidth to moderate overtly political discussions. Assume best intent and be excellent to each other.
- Not regarding using or support for Lemmy: context, see the list of support communities and tools for finding communities below
- Not ad nauseam inducing: please make sure it is a question that would be new to most members
- An actual topic of discussion
Looking for support?
Looking for a community?
- Lemmyverse: community search
- sub.rehab: maps old subreddits to fediverse options, marks official as such
- !lemmy411@lemmy.ca: a community for finding communities
~Icon~ ~by~ ~@Double_A@discuss.tchncs.de~
founded 5 years ago
MODERATORS
you are viewing a single comment's thread
view the rest of the comments
view the rest of the comments
You're conflating the blind spot and the macula there.
We do not have a blind spot in the middle of the retina. If that were the case it would be pretty problematic for vision. What we do have is what's called the Macula, an area of high concentration of cones and low concentration of rods. Cone cells give us highly detailed color vision, while rod cells only give us overall brightness, but are much more sensitive to light. That's why, as you mention, we're more sensitive to movement in our peripheral vision, and also why the center of our vision performs way worse in very low light situations. (Ever seen a faint star that seems to vanish when you try to look right at it? That's why)
We do actually have a fully blind spot, but that one sits not at the center of the retina, but off to the side. It's where the optic nerve enters the retina, and it doesn't have anything to do with better/worse perception of movement, it's just fully blind and always gets interpolated by the brain, it literally fills it up with what it thinks should be there. If you get a small object right into that spot for one eye and cover the other eye, it will just disappear.