Download Psych/Soc MCAT Prep Questions And Answers and more Exams Sociology in PDF only on Docsity!
Psych/Soc MCAT Prep Correct |
100% Verified | 2025
Version
Visual cues allow us to perceptually organize by taking into account the following cues: - ✔✔
- depth
- form
- motion
- constancy Describe retinal disparity. - ✔✔
- Eyes are about 2 .5 inches apart which allows humans to get slightly different views of objects of world around.
- gives humans an idea on depth What is convergence? - ✔✔- gives humans an idea of depth as well based on how much eyeballs are turned. gives humans a sense of depth When are the muscles of the eye relaxed and contracted? - ✔✔- things far away: muscles of eyes relaxed
- things close to us: muscles of eyes contract Describe binocular cues. - ✔✔- humans have two eyes which allow them to receive visual cues from the environment
- depth
Describe monocular cues. - ✔✔- humans have visual cues that they receive which they do not need two eyes for What do monocular cues provide? - ✔✔- give humans a sense of form of an object What senses of form do monocular cues provide? - ✔✔- Relative size: the closer and object it is perceived as being bigger
- Interposition (overlap): perception that one object is in front of another. an object that is in the front is closer
- Relative height: things higher are perceived to be farther away than those that are lower
- Shading & contour: using light and shadows to perceive form depth/contours - crater/mountain What type of cues allow us to sense motion? What type of sense exactly? - ✔✔Monocular cues
- Motion parallax: "relative motion" things farther away move slower, closer moves faster What type of cues allow us to sense constancy? - ✔✔- monocular
- out perception of object doesn't change even if the image cast on the retina is different. Different types of constancy include size constancy, shape constancy, color constancy Describe size constancy. - ✔✔- one that appears larger because its closer, we still think it is the same size Describe shape constancy - ✔✔- a changing shape still maintains the same shape perception
- ex: a door opening means the shape is changing. but we still believe the door is a rectangle
- experiment: goggles that make everything upside down and the perception of the world, and eventually you would accommodate over time, and flip it back over Describe sight in regards to sensory adaptation - ✔✔- down regulation or up regulation to light intensity
- down regulation: light adaptation. when it is bright out, pupils constrict (less light enters back of eye), and the desensitization of rods and cones become desensitized to light
- up regulation: dark regulation. pupils dilate-, rods and cones start synthesizing light sensitive molecules What is Weber's Law? - ✔✔- the threshold at which you're able to notice a change in any sensation is the just noticeable difference (JND)
- I=initial intensity of stimulus , change I= JND
- change I/initial intensity = k (constant)
- change I= IK What is the absolute threshold of sensation? - ✔✔- the minimum intensity of stimulus needed to detect a particular stimulus 50 % of the time Are the absolute threshold of sensation and just noticeable difference the same? - ✔✔No, JND is the smallest difference that can be detected 50 % of the time What factors can influence absolute threshold? - ✔✔- Expectations - ex: are you expecting a text
- Experience - ex: are you familiar of the phones text vibration sound
- Motivation - ex: are you interested in the response of the text
- Alertness - are you awake or drowsy ex: you will notice the text if you are awake What are subliminal stimuli? - ✔✔stimuli below the absolute threshold of sensation What are the three different types of information we gather about somatosenstation? - ✔✔- Intensity
- Timing
- Touch What are the 4 types of somatosensation? - ✔✔- Temperature (thermoception)
- Pressure (mechanoception)
- Pain (nociception)
- Position (proprioception) Describe intensity in terms of somatosensation. - ✔✔- how quickly neurons fire for us to notice
- slow = low intensity
- fast = high intensity Describe timing in terms of somatosensation. - ✔✔- neuron encodes 3 ways for timing: non adapting, fast adapting or slow adapting
- Non-adapting: neuron consistency fires at a constant rate
What is the signal detection theory? - ✔✔- looks at how we make decision under conditions of uncertainty - discerning between important stimuli and unimportant noise According to the signal detection theory, for any signal, we have - ✔✔noise distribution (background) What is bottom up processing? - ✔✔begins with stimulus. stimulus influences what we perceive (our perception)
- no preconceived cognitive constructs of the stimulus (never seen it before)
- data driven. and the stimulus directs cognitive awareness of what you're looking at (object)
- inductive reasoning. always correct What is top-down processing? - ✔✔- uses background knowledge influences perception
- theory driven. perception influenced by our expectation
- deductive reasoning
- like: creating a cube when it is not there. not always correct What are Gestalt Principles? - ✔✔Tries to explain how we perceive things the way we do.
- Similarity: items similar to one another grouped together by brain
- Pragnanz: reality organized reduced to simplest form possible
- Proximity: objects that are close are grouped together.
- Continuity: lines are seen as following the smoothest path
- Closure: objects grouped together are seen as a whole. mind fills in missing information
- Symmetry: the mind perceives objects as being symmetrical and forming around a center point What is the Law of Common Fate? - ✔✔- For example, if there are an array of dots and half the dots are moving upward while the other half are moving downward, we would perceive the upward moving dots and the downward moving dots as two distinct units What is the Law of Past Experiences? - ✔✔- Implies that under some circumstances visual stimuli are categorized according to past experience. If two objects tend to be observed within close proximity, or small temporal intervals, the objects are more likely to be perceived together. What are contextual effects? - ✔✔- the context in which stimuli are presented and the processes of perceptual organization contribute to how people perceive those stimuli (and also that the context can establish the way in which stimuli are organized) What is the conjunctiva? - ✔✔thin layer of cells that lines the inside of your eyelids from the eye What is the cornea? - ✔✔transparent thick sheet of fibrous tissue, anterior 1 / 6 th; starts to bend light, first part of eye light hits What is the anterior chamber? - ✔✔- space filled with aqueous humour, which provides pressure to maintain shape of eyeball; allows nutrients and minerals to supply cell of cornea/iris What is the pupil? - ✔✔- the opening in the middle of the iris
- the size of the pupil can get bigger/smaller based on the iris relaxing/contracting respectively. the pupil modulates the amount of light able to enter the eyeball
What is the choroid? - ✔✔pigmented black in humans, is a network of blood vessels that helps nourish the retina. It is black because all light is absorbed. Some animals have a different colored choroid which gives them better night vision. What is the sclera? - ✔✔- usually absorbs by the time the light gets to this. the whites of the eye, thick fibrous tissue that covers posterior 5 /6th of eyeball (cornea covers the anterior 1 /6).
- attachment point for muscles. extra layer of protection and structure of eyeball. lined with the conjunctiva What is transmission? - ✔✔the electrical activation of one neuron by another neuron What is perception? - ✔✔the conscious sensory experience of neural processing What is processing? - ✔✔the neural transformation of multiple neural signals into a perception What is sensation? - ✔✔requires a physical stimulus to be converted into a neural impluse What is light? - ✔✔- an electromagnetic wave
- EM spectrum : Violet ( 400 nm) - Red ( 700 nm) After light enters the eye what happens? - ✔✔- enters the pupil - > goes to the retina which contains rods and cones Explain what happens when light hits a rod. - ✔✔- there are 120 million rods for night vision
- light comes in, goes through pupil, and hits rod. Normally rods is turned on, but when light hits turns off
- when rod is off, it turns on a bipolar cell, which turns on a retinal ganglion cell, which goes into the optic nerve and enters the brain Explain what happens when light hits a cone cell. - ✔✔- there are 6 - 7 million cones
- 3 types: red, green, blue
- almost all cones are centered in fovea (details, which is the center of the macula)
- Phototransduction cascade Explain the phototransduction cascade. - ✔✔- what happens when light hits rod/cone
- light hits rods (which rod turns off) - > bipolar cell (turns on) - > retinal ganglion cell (turns on) - > optic nerve - > brain
- phototransduction cascade is the process of rod turning from on - > off What are bipolar cells? - ✔✔- are found in the retina
- these cels send visual signals from the rods and cones to the ganglion cells. What are ganglion cells? - ✔✔- are found in the retina
- bipolar cells send signals to the ganglion cells What is the optic nerve? - ✔✔- visual signals, after having been picked up by the rods and cones and transferred to bipolar cells to the ganglion cells, finally leave the eye through the optic nerve, which is really just the axons of the ganglion cells
- PDE takes cGMP and converts it to regular GMP [ So when light hits, lower concentration and increases concentration of GMP]
- Lots of Na+ channels on the rods allow NA+ ions to come in
- cGMP bound to Na+ channel, keeps the channel open and hence "ON", as cGMP concentration decreases, Na+ channel closes and turns Off
- when Na+ channels become unbound of cGMP, less NA+ enters the cell, then cell hyperpolarization and turn off
- next, bipolar cells ( 2 variants: on center and off center)
- when light hits rod, turned off - > on center bipolar cells active, off center bipolar cells inactive
- when on center bipolar cells turned on, this activates on center retinal ganglion cell, when sends signal to optic nerve to brain. *when dark, rod is turned on-> on center bipolar cells inactive, off center bipolar cells active *when off center bipolar cells turned on, this activates off center retinal ganglion cell, when sends signal to optic nerve to When does photopic vision occur? - ✔✔at high light levels When does mesopic vision occur? - ✔✔at dawn or dusk and involves both rods and cones When does scotopic vision occur? - ✔✔at very low light levels Rods are more sensitive to light than cones - ✔✔ 1000 x What is the three color ratio of cones? - ✔✔ 60 % red, 30 % green , 10 % blue What is feature detection? - ✔✔When looking at an object, you need to break it down into its component features to make sense of what you are looking at.
- there are 3 things to consider when looking at any object color, form and motion Explain color in terms of feature detection/ - ✔✔- cones
- trichromatic theory of color vision, 3 types of cones
- red ( 60 %), green (3 0 %), blue ( 10 %)
- remember, red objects reflect red, green objects reflect green and blue objects reflect blue Explain form in terms of feature detection. - ✔✔- we need to figure out boundaries of the object and shape of the object
- parvocellular pathway: good at spatial resolution (boundaries and shape - high level of details), and color. But poor temporal (can't detect motion-only stationary)
- cones are responsible Explain motion in terms of feature detection. - ✔✔- magnocellular pathway: has high temporal resolution (think time, motion) resolution [encodes motion]. But has poor spatial resolution; now color.
- rods responsible
- acronym: motion = magnocellular pathway What is parallel processing? - ✔✔detect/focus all information (color, form, motion) at the same time What are the two things we need for audition? - ✔✔- pressurized sound wave (a stimuli)
- at tip of cochlea (inner most part of the circle), where can the fluid now go? It can only go back, to the round window and pushes it out.
- the reason it doesn't go back to the oval window is because in middle of the cochlea is a membrane called the organ of Corti (includes the basilar membrane and the tectorial membrane)
- As hair cells move back n forth in the cochlea, electrical impulse is transported by the auditory nerve to the brain
- the above process of fluid going around the cochlea keeps occurring till the energy of the sound wave dissipates and stops moving. occurs more = more hair cells vibrate What is the place theory? - ✔✔- our perception of sound depends on where each component frequency produces vibrations along the basilar membrane. By this theory, the pitch of a musical tone is determine by the places where the membrane vibrates, based on frequencies corresponding to the tonotopic organization of the primary auditory neurons
- one is able to hear different pitches because different sound waves trigger activity at different places along the cochlea's basilar membrane Describe the upper membrane of the Organ of Corti. - ✔✔- the hair cells are called the hair bundle and it is made of little filaments
- each filament is called a kinocilium
- tip of each kinocilium is connected by a tip link which is attached to gate of K+ channel
- when the tip links get pushed back and forth by endolymph movement, they stretch and allows K+ to flow inside the cell from the endolymph
- Ca2+ cells get activate when K+ is inside, so Ca 2 + also flows into the cell, and causes an action potential, which then activated a spiral ganglion cell, which then activates the auditory nerve
The brain relies on the cochlea to differentiate between 2 different sounds how (how does auditory processing occur)? - ✔✔- Basilar tuning: there are varying hair cells in cochlea and allows brain to distinguish between high and low frequency sounds.
- hair cells at base (start of cochlea) are activated by high frequency sounds
- hair cells at the apex (end of the cochlea) by low frequency sounds
long wavelengths travel farther
- The primary auditory cortex (part of the temporal lobe) received all info from cochlea. It is separated by regions which detect different frequencies
- so with basilar tuning, brain can distinguish diff frequencies - tonotopical mapping Describe the somatosensory homunculus. - ✔✔- a map of your body in your brain. information all comes to the "sensory strip"
- a topological map of the entire body in the cortex. different areas of the body have signals that go to different parts on this strip
- the sensory cortex contains the homunculus
- brain has information that comes from various parts of the body How does proprioception work? - ✔✔- tiny little receptor (known as a spindle) located in our muscles sends signals that go up to spinal cord and to the brain. Spindle has a protein that is sensitive to stretching
- fast blocks slow
- by Ronald Melzack and Patrick Wall What are pheromones? - ✔✔- a chemical signal released by 1 member of the species and sensed by another species to trigger an innate response
- important in animals- linked to mating, fighting and communication When is a specialized part of the olfactory epithelium in animals? - ✔✔- accessory olfactory epithelium: sends projections to the accessory olfactory bulb which then sends signals to the brain Describe the structures within the accessory olfactory epithelium and its uses. - ✔✔- within you have a structure called the vomeronasal system
- in the vomeronasal system, there are basal cells and apical cells which receptors at tips
- molecule will come in and activate receptor on basal cell/apical cell here. Basal cell sends axon through accessory olfactory bulb to glomerulus, then mitral or tufted cell which eventually goes to the amygdala
- amygdala is involved with emotion, aggression, mating, etc. In temporal love, also involved with memory/decision making, emotional reactions
- signal transduction is where signal binds to receptor, which binds to GPCR - > depolarization - > signals goes to brain
- humans have a vomeronasal organ, but no accessory olfactory bulb. As a result, we rely very little on phermones
How is smell related to taste? - ✔✔- when you eat, molecules travel up back of throat and some go into back of your nose.
- if your smell is closed, you can't taste things well Describe olfactory epithelium - ✔✔- an area in the nostril where there are olfactory sensory cells
- separating the olfactory epithelium from the brain is the cribriform plate (bone with little holes that allow olfactory sensory to send projections into the brain) Describe the olfactory bulb - ✔✔- located above the cribriform plate
- a bundle of nerves that sends little projections through the cribriform plate into the olfactory epithelium, which branch off
- at end of each connection are receptors, each sensitive to 1 type of molecule All cells sensitive to benzene will fire to one olfactory bulb called - ✔✔a glomerulus : desgination point for various sensory olfactory cells that are sensitive to the sam molecule After the glomerulus, - ✔✔the receptors then synapse on another cell known as a mitral/tufted cell that project to the brain
- this organization is there because its easier for one cell to send a projection to the brain instead of thousands Why are smell (olfaction) and taste (gustation) different than other senses? - ✔✔- they don't synapse on to the thalamus and hence are ipsilateral while vision/hearing/touch are contralateral What is the labeled-line theory of olfaction? - ✔✔Describes a scenario where each receptor would respond to specific stimuli and is directly linked to the brain
