By Anju Miura

An image of a striped dress polarized what felt like the entirety of social media in 2015. Millions of people were debating whether or not it was blue and black or gold and white, and while the crazy dress debate may have seemed meaningless, there is something to be learned from it: what we see isn’t always the whole truth.

Although we were all seeing the same image of the dress, the colors we all saw varied. We as humans sometimes perceive things differently because of our process of recognizing, organizing and interpreting our environment — in other words, our perception.


Sensation and Perception

Sensation is a detection process by which our sensory organs respond to and translate the raw, physical information that will be sent to the brain. Perception is the active process of organizing sensation and making sense of the information.

Right now, you are receiving light from your device’s screen through your eyes which send the data of that sensation to your brain. Then, your brain interprets that what you are seeing is a series of words that compose this blog story.


Perceptual Set 

What kind of animal do you see in the above picture? Some will say they see a duck, while others swear they see a rabbit. We create our own perceptual set according to our expectations, experiences, moods and cultural norms that determine how we perceive our environment.

For example, we are more likely to see a duck if we find this picture in a dictionary of birds because we expect to see some kinds of birds. If you grew up seeing rabbits in your neighborhood, you may see a rabbit in the picture because it’s more familiar to you.

We sometimes perceive something that doesn’t actually exist, or we sometimes can’t perceive what does exist in our environment because of our perceptual set.



Human brains receive raw sensory information and interpret it, disassembling what we see into bits of information and reassembling to develop our original form of the world. Besides cultural factors and some disorders like color blindness, we sometimes see different colors, depending on how our brains interpret the raw visual information. 

Humans are able to see under different lighting conditions; dawn, noontime and sundown, and colors can change according to how much light they reflect. New York University Clinical Assistant Professor of Psychology Pascal Wallisch wrote that we perceive different colors from the picture based on our assumptions of lighting.

If you consider the photo of the dress was taken in a shadow, you are likely to see white and gold because your brain tries to discount the color of the shadow that represents blue light. If you see black and blue, on the other hand, your brain interprets the photo was taken in light, discounting yellowish color.


Human Face—Thatcher illusion

Perceptual set also applies to human faces. When we see an upside-down face, it becomes more difficult to detect local feature changes, despite identical changes being obvious in an upright face.

Recognition by components theory

Psychologist Biegerman believed we identify objects by their components and relationships between them. For example, human face has two eyes, eyebrows, nose and mouth. By looking each facial part, we see this same, consistent features and recognize it as a human face.

However, if this theory truly explains how we recognize objects from different perspectives, we might be easily able to find out any discrepancies in the upside-down face of Thatcher.


Configural Theory

We can hardly tell Thatcher’s face is disfigured in the upside-down picture, but most of us can identify the woman as Margaret Thatcher. The configural theory explains that the objects presented in context are easier to be recognized than the objects presented alone.

If the picture (either upright or upside-down) only shows her eyes, we are less likely to identify whose eyes are in the picture.