Did you feel something? (SENSATION)
Seeing is believing. (PERCEPTION)
Theories
Gestalt Principles
The Senses
100
This is what happens when your eyes see light, your nose smells a flower, and your skin feels a cold breeze. It's the first step in knowing what's happening around you.
What is sensation?
100
While sensation is the physical process of detecting stimuli, this is the psychological process of giving those stimuli meaning like when you recognize a familiar song from a single note or bar.
What is Perception?
100
This theory states that for a signal to be detected, it must cross a certain level of intensity. It's the "all-or-nothing" rule for sensing something. It's the reason a mosquito landing on your arm might not be noticed, but a small fly definitely is.
What is Threshold Theory?
100
This principle states that objects that are close together tend to be perceived as a group. It's why you see these dots as three separate groups instead of 15 individual dots.
What is Proximity?
100
The lens and cornea are two key parts of the organ responsible for this sense, working together to focus incoming light.
What is Sight (Vision)?
200
Think of these as the VIP bouncers at the door of your body's senses. They're the special cells in your eyes, ears, and skin that only let certain information in to be processed.
What are sensory receptors?
200
This is what you're experiencing psychologically when your senses deceive you, like seeing a straight stick appear bent in a pool of water.
What is an illusion?
200
It's the reason why your vision seems clear and singular even though you have 2 eyes. The process where your brain takes the slightly different images from each of your eyes and merges them into a single, three-dimensional image.
What is Binocular Fusion?
200
This is why you likely see rows of circles and rows of squares in this image, rather than a single, jumbled pattern. 
What is Similarity?
200
The cochlea, a snail-shaped organ, is crucial for this sense as it turns vibrations into neural signals.
What is Sound (Hearing)?
300
It's the essential process where the energy of a stimulus, such as the pressure of a handshake, is converted into an electrical signal that travels along a nerve.
What is sensory transduction?
300
When you hear your name called in a crowded room, this is the processing that allows your brain to filter out the other noise and focus on the familiar sound. It’s a "big picture" approach where your brain uses existing information to quickly make sense of new sensory input.
What is Top-Down Processing?
300
This theory explains most forms of colorblindness, which often result from a deficiency in one of these three cone types.
What is Trichromatic Theory?
300
This is the tendency for our brains to "fill in the blanks" to perceive a complete, whole object even when some parts are missing.
What is Closure?
300
It's often strongly linked with the sense of smell, as a blocked nose can make it difficult to appreciate the flavors of a meal.
What is Taste (Gustation)?
400
Your brain is a master at this, tuning out constant stimuli, so you don't feel the clothes on your body all day long.
What is sensory adaptation?
400
It's the brain's impressive feat of maintaining a stable perception of an object's size, shape, or color, even as the sensory input changes. Like the perceptual ability to see a door as a rectangle, even when it's open and looks like a trapezoid from your perspective.
What is Constancy?
400
This theory of hearing proposes that the rate at which a sound wave vibrates determines the pitch we hear.
What is Frequency Theory?
400
This is why you see these wavy lines as continuous paths that flow through the image, instead of a series of broken pieces. 
What is Continuity?
400
This is the only sense that sends signals directly to the brain's limbic system, which is associated with memory and emotion. It relies on olfactory receptors in the nasal cavity to detect airborne chemical molecules.
What is Smell (Olfaction)?
500
This is the lowest amount of sound, light, or touch that you can notice half of the time. Think of it as the quietest whisper you can possibly hear from across the room.
What is absolute threshold?
500
It's the process that allows you to identify a new object by analyzing its individual features, like its shape, color, and texture. It's a "data-driven" process where the brain builds a perception based on the raw, incoming sensory information.
What is Bottom-Up Processing?
500
It explains why you see a ghostly green afterimage after staring at a red object for a long time.
What is Opponent-Process Theory?
500
This principle explains why the words you are reading right now stand out against the white page they are printed on.
What is figure-ground?
500
This sense is not limited to one organ but is spread across the entire body, from our fingertips to our toes. It allows us to feel pressure, temperature, texture, and pain.
What is Touch (Somatosensation)?