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Lynne: The next visual characteristic of CVI we're gonna talk about is movement. Movement is integral to vision. Your eyes are constantly making small movements called saccades. Without this little tiny movements of your eyes, you pretty much wouldn't be able to see anything because just like, if you smell a really strong odor. After awhile, you stopped smelling it, even though the odor's still there. And that's because of, you know, that information has bombarded your receptors, and so they no longer are firing. And so if your eyes were not making this constant little movements, they would just get bombarded by static visual information, and you would just grayout, you know. You would stop seeing anything.

Sara: And isn't that called habituation?

Lynne: Um...


Sara: I think it is.

Lynne: And so movement is, you know...your brain is hard-wired to see movement. If you see something move, especially in your periphery, you're gonna turn your head. It's reflective. It don't even have to think about it. You almost cannot not do it. Your. . .movement bypasses your cortex and is processed in your brain stem. So, it's a very, um, reflexive, you know.

Sara: It is reflexive. It's like, uh...

Lynne: Uh-hmm.

Sara: It's a survival skill, basically.

Lynne: Right.

Sara: And it did need to be one of the first ones that we were able to do because if we didn't detect that and act quickly...In the past, a long time ago,we would probably, would've been eaten by something.

Lynne: Right. The saber-toothed tiger. So, um...People with CVI can generally see things that move better than they can, see things that are static. And, so...We see this more in the periphery, usually in practice, but it could be any kind of movement. And there are also kids that may only see things that move.

Sara: And that's... The periphery is the one with all of the rods which are more about detecting movement than the cones are. So, that makes sense that the periphery would be better at detecting movement.

Lynne: So, reflection is also processed by your brain as movement. And we have some video.

Sara: This is, um...These reflective items are what Christine Roman calls supercharged movement. And that they're really hard to ignore.

It can be a very invasive visual thing. And the video that we are going to watch right now is of a child who is not somebody who fixates on a whole lot of stuff. And we're using something that's not her favorite color.

But as you'll see in this, she really has a hard time looking away from this shiny thing that is constantly, basically moving as far as the way her brain is perceiving it. And so, this is the best tracking, the best following that we got from this child. And it was on a super charged shiny thing. So, let's watch this example.

[Video Dialog]

This is pretty exciting.



[end Video Dialog]

Sara: The second example that we have is of a student who the'll see him responding to this movement. And he response more quickly than he does to any visual stimuli as...You know, when he normally responds to something, it takes him quite awhile. But with this movement going on, he's looking very quickly. And what's also interesting about this is that, um, when the item... It's on a light box. It's the little spinning... What do they call it? Hypnodisc or something. And when that is moving, he actually can't look at it 'cause the pattern is weird for him, but the initial movement of it draws his attention almost immediately. So, it's pretty cool.


Lynne: One more thing about movement. It's not just the object that has to be moving or maybe moving. You may have kids that move their heads, so that they can see things better...

Sara: Like this.

Lynne: ...or kids that move their entire bodies. We have kids that, um... Students that may constantly pace. And one of the reason they may do that is because they can see when they're moving and they can't see when they're not.

Sara: It's an adaptation that the kids make on their own, so that they can see...

They want that visual information.

Lynne: Right.

Sara: They'll do what it takes to get it.

Lynne: That's right.