Psychology Ch. 5 Flashcards
Sensation
when your body picks up things happening around you (like seeing light or hearing sound) using special parts called sensory receptors, and then sends this information to your brain.
Perception
what your brain does with what is happeneing around you (the sensory info) . It takes all the different pieces of information, puts them together, and helps you understand what they mean. It’s like your brain is telling you, “That’s a dog barking” or “A car is honking its horn.”
Transduction
the process where these sensory receptors translate the outside information (like the tap on your shoulder) into electrical signals. Once the information is in the form of electrical signals, it can travel along the nerves to your brain. When it gets to your brain, your brain can understand the message and react to it.
Absolute threshold
The lowest level of a stimulus — like sound, light, or touch — that an individual can detect at least half the time it is presented
like the volume knob on a radio. Imagine you’re turning up the volume very slowly from complete silence. The absolute threshold is the point at which you first start to hear the music
Difference threshold
The just noticeable difference between
two stimuli (the minimum amount
of change required for a person
to detect a difference 50% of the
time)
noticing a change in the intensity of a stimulus that’s already present.
Every taste experience is composed of a mix of what five basic qualities?
sweet, salty, sour, bitter, & umami (savory)
What are the stimuli for smell?
Where are the smell (or olfactory)
receptors located?
airborne chemical molecules that we encounter in our environment. These molecules are often released from objects or substances and become part of the air around us. When we breathe in, these molecules enter our nose. Olfactory epithelium (or mucosa) is a thin layer of tissue
embedded with smell receptors, which transmit information to the olfactory bulb, which is the brain center for smell.
Orbitofrontal cortex
Receives info from smell, taste, and visual systems
Flavour perception
Mechanoreceptors
Respond to mechanical distortion or pressure
(The most sensitive mechanoreceptors are actually found in the cochlea responsible for sound transduction)
activated by things like touch, pressure, stretching, and sound vibrations.- When something physically touches or applies pressure to your skin, or when your muscles and other tissues stretch, these mechanoreceptors get activated.
They convert this mechanical energy (like touch or pressure) into electrical signals.
These signals are then sent to the brain, where they’re interpreted as different sensations like touch, pressure, vibration, and even sound.
The primary somatosensory cortex
part of your brain that acts like a map for touch sensations. Each part of your body is represented on this map, and the more sensitive the body part (like lips or fingertips), the larger its area on the map. This helps your brain process and understand how things feel when you touch them. (Sensory homunculus)
Wilder Penfield
A Canadian neurosurgeon and one of the pioneers in the field of neurology. He made significant contributions to our understanding of the brain and its functions, particularly through his work on the mapping of the human brain’s sensory and motor areas.
Nociceptors
your body’s alarm sensors for pain. They notice things that could hurt you, like extreme heat or a sharp object. When they detect something harmful, they quickly send a message to your brain, and that’s when you feel pain. They help keep you safe by warning you about possible dangers.
Myelinated (“A delta”) fibres
Type of nerve fibers in your body that are responsible for transmitting signals related to sharp, immediate pain. These fibers play a role in quickly signaling your brain when you experience something potentially harmful, like touching something hot or getting a sharp cut
Lightly or non-myelinated (“C”) fibres
Another type of nerve fibers in your body that transmit signals related to dull, steady pain. These fibers are involved when you experience a lingering, persistent ache or discomfort. Their slower transmission is associated with a more prolonged and lingering perception of pain. This type of pain might be related to the body’s need for recuperation or healing, signaling that something might be wrong and requiring attention or care.
Gate control theory of pain
For pain to be experienced, pain receptors must be activated AND the neural “gate” in the spinal cord must allow the signals through to the brain
If the gate is “open” - pain is experienced
If the gate is “closed” - pain is reduced (or prevented)
e.g., taking meds closes the gate.
What is the sensory homunculus?
A tiny person inside your brain. This little person has a map that shows how much attention your brain gives to different parts of your body when you feel things like touch or temperature. But, this map doesn’t show things in the right sizes; it makes some body parts look bigger or smaller based on how much your brain cares about them.
Accommodation (eye)
Muscles change the shape of
the lens, flattening it to focus on distant objects,
and thickening it to focus on closer objects
Photoreceptors
Tiny sensors in your eyes. When light particles (photons) hit them, they start a chemical reaction. This reaction creates an electrical signal, like a message, that your brain can understand. So, in simple terms, photoreceptors help your eyes turn light into signals that your brain can use to see things.
Rods
Tiny cells in your eyes that work in low light. They help you see things in black and white. You’ve got lots of these—around 120 million on the sides of your retinas. They’re the reason you can see in the dark and notice basic shapes and shades.
Cones
Eye cells that work better in bright light and help you see colors. You have fewer of these—around 6 million in each retina, mainly in the center part called the fovea. Cones are the reason you can enjoy a colorful and vibrant view on a sunny day.
What are the three types of cones
S cones – short wavelengths – blues
M cones – medium wavelengths – green
L cones – long wavelengths – red
The cornea
the windshield of your eye - light comes in through the cornea, the cornea and the lens work together to bend light (refract light) onto the retina
The pupil
Hole in the iris controlling amount of light in
Iris
The colored part of our eye muscles - able to control the pupil size.
Retina
The very back photoreceptors. These cells translate the energy from light into a language that your brain can understand
e.g., When you see a yellow flower - the retina translates this so our brain can understand what you are seeing is a yellow flower.
Fovea
A little pit right at the back of your eye on the retina. It’s a special spot because it’s where your vision is super sharp. Imagine it as the eye’s high-resolution area, like the center of a camera lens that captures the finest details
Optic disc
A hub where the wires (axons) from your eye gather to form a nerve that goes to your brain. It’s the entry point for messages from your eyes to your brain. But here’s the tricky part: this hub creates a tiny “blind spot” in your vision
Label this eye
https://www.google.com/search?q=empty+label+of+eye&sca_esv=590380016&rlz=1C5CHFA_enUS1071CA1075&tbm=isch&sxsrf=AM9HkKm5aMnSC9dvFUZsWLkY7CS9-krDZw:1702483438589&source=lnms&sa=X&ved=2ahUKEwjW896E5YyDAxV7CTQIHYxMBzcQ_AUoAXoECAIQAw&biw=1470&bih=738&dpr=2#imgrc=IcSgv8Sc2wCf5M
Visual transmission
Rods + cones –> bipolar, amacrine, horizontal course, ganglion cells/optic nerve
Trichromatic theory
the perception of color is determined by the particular ratio of color among these three types of receptors(L. M. S)
Opponent processing theory
(Hering 1920) Focus on ganglion cells in the retina
Three opposing pairs (if one colour in the pair stimulated, the other is inhibited):
* Red / Green
* Yellow / Blue
* White / Black
If you stare at a red object for a long time, the red cells in your eyes get tired and stop responding as much. When you then look away at a neutral background, the green cells (which were turned off before) are now more active compared to the tired red cells. This is why you might see a green afterimage where the red object was.
Motion sensitive neurons
Cells in the visual system that respond to movement. When you repeatedly expose these neurons to a specific type of motion, they can become fatigued or adapt. This adaptation can result in a perceptual phenomenon known as a motion aftereffect, and a classic example of this is the “waterfall illusion.”
When you stare a a waterfall for too long other objects can looks like they are in motion.
Dorsal
on the top) (dorsal fin on a dolphin) -the parietal pathways - specialized for spatial perception - us understanding where objects are in space relative to ourselves. (how far I need to reach to pick something up, the shape my hand has to take to pick up my phone vs coffee)
Ventral
“what’ stream - down to the temporal lobe - allowing us to determining things and say (yes that is my iphone..
agnosia (trouble for recognizing things) ; prosopagnosia (trouble for recognizing faces.)
Figure-ground relationship
Whatever is not the figure (the focus of visual field) is automatically assigned as background
Illusory Contours
Imagine seeing lines or shapes that aren’t really there. Illusory contours trick our brains into thinking there are outlines or borders, even when nothing is physically outlining the objects
Proximity
The closer two figures are, the more likely we
are to group them together and see them as being part of the same object
Similarity
We tend to group figures according to how
closely they resemble each other
Continuation
We tend to interpret intersecting lines as
continuous rather than as changing direction radically
(branches behind the tree)
Closure
We tend to complete figures that have gaps
Picture of panda
Retinal Disparity
Because we have two eyes the visual info we have with only one eye open is different, so what the brain does is it combines info from both eyes using disparity between two retinal imaged to compute distances
Monocular depth cues
Include occlusion, relative size,
familiar size, linear perspective, texture gradient, and
position relative to horizon
Occlusion: When one object covers part of another, the covered object seems further away.
Relative Size: Smaller-looking objects are perceived as more distant if we know their typical size.
Familiar Size: We use our knowledge of how large familiar objects are to judge their distance.
Linear Perspective: Parallel lines seem to meet in the distance, like railroad tracks converging.
Texture Gradient: Objects look more detailed when close and less detailed when far away.
Position Relative to Horizon: Objects near the horizon seem farther away than those far from it.
Motions cues (motion parallax)
for depth perception include the motion
parallax: Objects that are farther away seem to move more slowly that objects that are close
Relative motion
when you are moving and you fixate on a point, anything closer appears its moving in the opposite direction.
Bottom-up processing
you don’t start with a preconceived idea of what you’re looking at. Instead, you start with the small details, like colors, lines, or textures, and then combine these details to form a complete understanding or perception. It’s like building your understanding from scratch, starting with the simplest pieces of information and working your way up to the bigger picture.
Top-down processing
Imagine you have a plan in your head before you start building a tower of blocks. starting with that plan (the higher-level information) and then using it to influence how you arrange the blocks (the lower-level processing). Similarly, information from your expectations and previous knowledge guides how you see and understand things, affecting the way your brain processes incoming information from your senses.
Split brain patients
corpus callosum is getting severed,
Contralateral organization (left side controls right)
Lateralization of function (certain parts have their own specialty)
Left hemisphere
The vocal hemisphere (when people are making a vocalized response it is coming from the left hemisphere.)
Right hemisphere
being better at spatial relations - more responsible for facial perception.
Spatial
anything related to space and the area around us
What happens in a split brain patient if there is a teddy bear to their right and a duck to their left?
The teddy bear on the right gets processed by the left hemisphere which is vocal, so when they are asked they will say that it is a teddy bear. - the right hemisphere will point at a bathtub when shown the picture of the duck
When you asked people to explain why they pointed to these images - only the left hemisphere can answer so it makes up a story (the major interpreter)
“The teddy bear sleeps in bed with the child. And children have baths before they go to bed.”
Fusiform face area (FFA)
Area of the brain that becomes particularly active when people look at faces (some evidence that it is an “expertise” area and not just for faces)
Located at the intersection of the
occipital and temporal cortices,
and is usually larger on the right side
Psychophysics
Testing how your mind and your senses work together. It’s about figuring out the connection between what you experience and what’s really happening in the world. e.g., How bright a light is or how loud a sound is.
Signal Detection Theory
Noticing a meaningful signal (like a quiet sound or a faint light) in the midst of background noise and deciding whether to respond or not.
Sensory adaptation
When your senses get used to something after being exposed to it for a while. It’s like when you first put on a watch, and you feel its weight on your wrist, but after a while, you don’t notice it anymore
Binocular cue
Visual hint that helps you see depth and perceive the world in three dimensions, using both of your eyes. It’s a clue your brain gets when it compares the slightly different views each eye has of the same scene.
Cochlea
A snail-shaped, spiral part in your ear that helps you hear. It’s a vital component of the inner ear. When sound enters your ear, the cochlea turns it into electrical signals that your brain can understand.
Gustation
Taste
gestalt principles
Organize what we see. They help us make sense of the world by grouping things together in meaningful ways. Think of it as your brain’s way of organizing individual elements into a whole picture.
e.g., Similarity: Things that look alike are grouped together.
taste bud
Tiny sensory organs on your tongue that help you taste different flavors. They’re like the little taste detectors in your mouth. When you eat something, these taste buds send signals to your brain, allowing you to experience and identify different tastes like sweet, salty, sour, and bitter.
vestibular system
(Inner ear) Your body’s internal balance and orientation system. It’s responsible for helping you stay upright, maintain balance, and sense your body’s position in space.
