A Dog’s View of Human Optical Illusions

Our perceptions deceive us in peculiar and reproducible ways. These perceptive deceptions are built into our make up, hardwired into our neurons. Some of the most striking examples of this are visual illusions. What we see is definitively not what really is. This is, in important ways, part of what it means to be human…

Did it have to be this way? Do dogs see the world the same ways as us?

In the Ebbinghaus-Titchener illusion, the two central circles have equal diameters. To humans, the circle surrounded by smaller circles appears larger. According to one study, the effect is reversed in dogs.

In the Delboeuf illusion, the two central circles have equal diameters. To humans, the circle surrounded by the smaller ring appears larger. Two studies have found that dogs don’t appear to perceive any difference.

Ponzo illusions use lines or grids to distort the relative sizes of two shapes. Humans typically perceive the rectangle on the left in this image to be larger. Several studies by one research group suggest dogs don’t perceive a difference.

In the Muller-Lyer illusion, the lengths of two identical lines appear distorted by arrowheads positioned at either end. Humans typically perceive the upper line as longer. Dogs trained to pick the longer line also pick the top line, but these findings might be explained by the animals choosing the larger stimulus overall, rather than perceiving the horizontal line as longer, as humans do.

Navon figures such as these can be perceived either globally—in this case, as an E and R— or locally, as an arrangement of Ns and Ss here. Some research suggests that humans are better at perceiving global stimuli than dogs are.

2 Likes

Very interesting topic! It makes me wonder about all of the diverse visual perceptions that may exist among animals.

1 Like

Have you thought about all of the diverse visual perceptions that may exist among humans?

We cannot actually compare our perception. I have no idea as to how you perceive reality and you have no idea as to how I perceive reality.

We compare our verbal descriptions of our perception. We cannot compare the perceptual experience itself.

2 Likes

Good point, Neil. Along those lines… Is Tetrachromacy Real? Definition, Causes, Test, and More

Yes, I have. My comment was more so referring to the physical or species specific related differences of visual perception.

1 Like

This topic was automatically closed 7 days after the last reply. New replies are no longer allowed.