Chapter 4 Flashcards
Sensation
The process of your senses (eyes, ears, skin, nose, tongue) detecting information from the world and sending it to your brain.
Perception
How your brain interprets the raw information from your senses (eyes, ears, skin, nose, tongue) to make sense of the world.
Transduction
When your senses turn external energy (like light, sound, or touch) into electrical activity within neurons.
Sense Receptors
Specialized cells that detect stimuli and turn them into signals for the brain.
Sensory Adaptation
When your senses get used to a constant stimuli and you stop noticing it over time.
(Ex. You notice the smell of a room when you first enter it then you get used to it over time).
Psychophysics
The study of how we perceive sensory stimuli based on their physical characteristics.
It looks at how strong a stimulus has to be before we notice, detect or react to it.
(Ex. How soft can a sound be before we hear it (absolute threshold)).
Absolute Threshold
The smallest amount of stimulus that the nervous system can detect at least 50% of the time.
Just Noticable Difference (JND)
The smallest change in a stimulus that someone can detect.
(Ex. Your listening to music on your phone but the volume is turned so low that you can’t hear it, when you turn the volume up to the point where you can JUST hear it, that’s the JND).
Webers Law
The bigger something is, the bigger the change has to be be for it to be noticeable.
(Ex. Your in a dark room and someone turns on a lamp, you will notice the change immediately.
But if you’re outside when it’s bright and someone turns on the same lamp, you probably won’t notice it).
Signal Detection Theory
Theory regarding how stimuli are detected under different conditions. Explains how we notice things/signals in a noisy or uncertain environment.
(Ex. Your at a concert and your friend calls your name, if your paying attention you may hear it, if your distracted, you might not).
Synesthesia
Condition where one sense triggers another one in an unusual way,
People experience cross-modal sensations.
(Ex. Hearing sounds when they see colours).
Selective Attention
Process of selecting one sensory channel and ignoring or minimizing others.
Brains ability to focus on one things while ignoring everything else around you.
(Ex. The cocktail party effect - you can focus on one conversation at a noisy party, while ignoring the other voices).
Inattentional Blindness
Failure to detect stimuli thats in plain sight when our attention is focused elsewhere.
(Ex. Walking into a pole or person while on your phone).
Hue
The colour of light.
Pupil
Black circular hole where light enters the eye.
- Small pupil = bright room.
- Big pupil = dark room.
Cornea
The clear, outer layer of the eye that helps focus light on the retina so you can see.
Cornea
The clear, outer layer of the eye that helps focus light on the retina so you can see.
Lens
The part of the eye that changes its shape (from thick to thin in response to distance) to keep images in focus.
Accommodation
Changing the shape of the lens to focus on objects near or far.
Retina
The light sensitive layer at the lack of the eye that turns light into neural activity so you can see.
- Contains photoreceptors (special cells that help you see).
Fovea
Central portion of the retina.
Acuity
Sharpness of vision.
Rods
Enables us to see basic shapes and forms, we rely on rods to see in low levels of light.
Cones
Give us our colour vision, sensitive to detail, requires more light than rods do.
Dark Adaptation
When your eyes adjust to low light after being in bright light.
Happens because your retina becomes more sensitive to light over time.
Optic Nerve
Nerve that travels from the retina to the brain.
Carries visual information from the eye to the brain, allowing us to see.
Blind Spot
Part of the retina containing no rods or sense receptors.
Colour Blindness
Inability to see some or all colours.
Red-Green Dichromates - they have 2 types of cones and are missing 1. Cant distinguish reds from greens or different shades within these categories.
X chromosome is responsible for producing photo pigment, women have 2 X chromosomes, men have 1 which is why men are more prone to being colourblind.
Opponent Process Theory
Theory that we perceive colours in terms of three pairs: either…
1.) Red or Green
2.) Blue or Yellow
3.) Black or White
Our eyes can’t see both colours in a pair at the same time - we don’t see a “reddish-green” because they cancel each other out.
Audition
Sense of hearing.
Timbre
The complexity or quality of sound that makes musical instruments, human voices, or other sources sound unique.
Cochlea
Bony, spiral-shaped sense organ used for hearing.
Organ of Corti
Tissue containing the hair cells necessary for hearing.
Basilar Membrane
Membrane supporting the organ of Corti and hair cells in the cochlea.
Place Theory
Different parts of the cochlea respond to different pitches.
High sounds = base of the cochlea.
Low sounds = tip of the cochlea.
(Ex. Like keys on a piano, each area responds to a different note).
Frequency Theory
Rate at which neurons fire the action potentials reproduces the pitch.
Olfaction
Our sense of smell.
Gestation
Our sense of taste.
Taste Bud
Sense receptors in the tongue that respond to sweet, salty, sour, bitter, umami, and fat.
Pheromone
Odourless chemical that serves as a social signal to members of one’s species.
Somatosensory
Our sense of touch, temperature, and pain.
Gate Control Model
Ronald Melzack + Patrick Wall
Explains how we feel pain, it says the spinal cord has a “gate” and that controls pain signals going to the brain.
- When the gate is closed, we feel less pain.
- When the gate is open, we feel more pain.
1.) Small Nerve Fibres: sense the pain and opens the gate by sending the signal to the brain.
2.) Large Nerve Fibres: responds to normal sensations of touch/pressure, closes the gate.
Phantom Pain
Pain or discomfort felt in an amputated limb.
Mirror box has been used to help this pain.
Proprioception
Our sense of body position.
Vestibular Sense
Our sense of equilibrium or balance.
Semicircular Canals
3 fluid-filled canals in the inner ear responsible for our balance.
Parallel Processing
When the brain handles multiple types of information at the same time instead of one at a time. It helps us see, think, and react quickly.
(Ex. Recognizing red, blue, green).
Bottom-Up Processing
Processing in which a whole is constructed from parts.
Learning from new information.
(Ex. You see a new fruit for the first time do you examine its shape, colour, texture, smell to figure out what it is).
Top-Down Processing
Conceptually driven processing influenced by beliefs and expectancies.
Using what you already know.
(Ex. You walk into a dark room and know where the furniture is because you’ve been there before).
Perceptual Set
When expectations influence perceptions (what you see, hear, or feel).
Perceptual Constancy
The process in which we perceive stimuli consistently no matter the conditions. This helps us see the world consistently no matter the angle, distance, or lighting.
Size Constancy
Our ability to perceive objects as the same size no matter how far away from us they are.
(Ex. A car driving away looks smaller but is not shrinking).
Colour Constancy
Our ability to perceive colour consistently across different levels of lighting.
Depth Perception
Ability to judge distance and see the world in 3D.
(Ex. It allows us to reach for a glass and grab it rather than knocking it over and spilling it).
Monocular Depth Cues
Relying on one eye.
Binocular Depth Cues
Requires both eyes.
Subliminal Perception
When your brain processes information without you being aware of it. You see, hear, or sense something, but it’s too quick for you conscious mind to notice, but your subconscious mind picks it up.
(Ex. The Amazon logo has an arrow from “A” to “Z,” suggesting they sell everything, but many people don’t notice it consciously).
