Look at one point - can you make the train change directions?

In summary: Lisa have been discussing their experiences with changing the direction of a train GIF and a ballerina spinning. Dave mentions that he can easily change the direction of the train by focusing on different points, but struggles to do so without moving his eyes. Lisa shares that she can only control the ballerina's direction by looking at her shadow, but realized that she can manipulate it through her peripheral vision. They also joke about making the train stay at the station and making milkshakes. In summary, Dave and Lisa discuss their ability to change the direction of a train GIF and a ballerina's spinning, using different methods such as focusing on different points or using peripheral vision. They also joke about making the train stay stationary and making milksh
  • #1
lisab
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When I look at the top of the gif, the train comes toward me. When I look at the bottom, it goes away from me.

I have a hard time making it change while looking at the same spot, though.

2gQNvar.gif
 
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  • #2
I can make it roughly change directions simply shifting my gaze a few pixels to the left and right. I don't know if I can do it without moving my eye at all.
 
  • #3
I can stare at about the window level of the train and think about it coming towards me and it does, and then think about it going away from me, and it does. I can do that pretty easily.
This reminds me of the ballerina one, where she can switch directions by just thinking about it. I can't look at her and change her spinning direction, I have to look at her shadow. She naturally always spins clockwise for me, but if I look at her shadow, I can make her spin counterclockwise, but then she's stuck spinning counterclockwise until I look at her shadow again.
220px-Spinning_Dancer.gif


But I just realized, if I look at the image through my peripheral vision, and not directly, I can think about her spinning one way, and that's what I'll see. I only have control over her when not looking directly at her.
 
  • #4
I can make it stay at the station and just wobble there for no reason. The passengrs certainly cannot get on or off.
 
  • #5
256bits said:
I can make it stay at the station and just wobble there for no reason. The passengrs certainly cannot get on or off.
Heh heh. Making milk shakes.
 
  • #6
That's a good one Lisab :)

Dave
 

1. How can you make the train change directions just by looking at one point?

The concept of making the train change directions just by looking at one point is based on the optical illusion known as the "spinning silhouette." By focusing on one point while the train moves in a circular motion, the brain perceives the train to be changing directions when in reality, it is still moving in the same direction.

2. Is the train really changing directions or is it just an illusion?

The train is not physically changing directions. It only appears to be changing directions due to the optical illusion created by the spinning silhouette. This illusion is a result of the brain's interpretation of the visual information received from the eyes.

3. Can this phenomenon be observed with any moving object or only with a train?

This phenomenon can be observed with any object that moves in a circular motion and has a distinct shape. It is commonly demonstrated with a train, but it can also be observed with a car, bicycle, or even a spinning top.

4. What causes the train to appear to change directions?

The phenomenon of the train appearing to change directions is caused by the brain's perception of the spinning silhouette. When we focus on one point while the train is moving in a circular motion, our brain tries to make sense of the visual information and creates the illusion of the train changing directions.

5. Is there a scientific explanation for this illusion?

Yes, there is a scientific explanation for this illusion. It is known as the "motion aftereffect" or the "waterfall illusion." It occurs when the brain adapts to a constant stimulus, in this case, the circular motion of the train, and perceives the opposite motion when the stimulus is removed, making the train appear to change directions.

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