MCAT PREP PYSCH/SOC

Visual cues allow us to what

perceptually organize

What are the 4 visual cues

depth, form, motion, constancy

Constancy

Allows us to evaluate objects with stability and sanity

Binocular cues

or cues that require both sets of eyes to give a sense of depth

Retinal disparity

Since eyes are about 2.5 inches apart but vary from human to human it allows for a different view of objects in the world around you

Convergence

gives human idea of depth which is based on eyeball movement

Eye muscles contract when blank and muscles relax when blank

close, far away

Monocular cues

are cues that do not require both eyes to percieve them which gives the form of the object

Form of an object is broken down into 4 subtopics what are they

Relative size, interposition, relative height, and shading contour

What is the form (relative size)

Relative size can be inferred with one eye (the closer something is, the bigger it is perceived to be)

What is the form (interposition/overlap)

Perception that one object is in front of another

Relative height

things higher are perceived to be farther away than those that are lower.

Shading and contouring

Using light and shadows to percieve form depth countour and things alike

Monocular cues give a sense

of motion

Motion parallax

Things farther away move slower, closer things move faster

Size Constancy

An object that appears larger because it is closer we will still think it is the same size. looking through a peephole into a trapezoid room and seeing a rectangle is a good example of this

Shape Constancy

a changing shape will still remain the same shape perceptually. a door opening is a good example of this

Color Constancy

despite changes in the lighting an object will still remain the same color

What is the only binocular cue?

Depth

What are the monocular cues?

Form, motion, constancy

Retinal Disparity is directly related to

binocular cues

Sensory adaption

These are senses that are adaptive and can change how thye reach to stimuli

What senses can be adapted?

Hearing, touch, smell, proprioception, sight

Hearing adaption

The idea that your ear will adapt to the frequency or the magnitude of a sound (ex. when there is a high noise, the inner muscles of the ear will contract allowing the sound to be dampened, while if the noise halts, the inner muscles of the ear will relax)

Touch adaption

Temperature receptors are dampeneed over time to recieve stimuli differently (the generalization of moms and tortillas lol)

Smell adaption

Receptors in your nose are desensitized over time (adapting to a strong smell in a room over a long period of time…juicy crab)

Proprioception

The sense of the position of your body in a space (ex. closing your eyes and touching your nose under the influence of alcohol and it is unlikely you will be able to find it)

What is balanced based on

Vision and the vestibular system (ear system)

Sight adaption

how the eyes contract and adapt to sense light and how much you are able to interpret

Sight Adaption: Down Regulation

Bright light adaption. When its bright out the pupils will contract so that less light enters the back of the eye

What does down regulation lead to

rods and cones being desensitized to the light

Sight Adaption: Up Regulation

Dark regulation. Pupils will dilate and rods and cones will synthesize sensitive light molecules that are available for them to latch onto.

Weber’s Law

We notice absolute changes, NOT percentage changes (ex. You are sitting in a room with 100 candles…if one more is lit, it is very unlikely that you will be able to notice the change). How much stimulus there was to begin with determines how much stimulus is needed to notice a change

What is the variable for noticeable difference

ND

What is the variable for the intensity of stimuli

I

What is the equation for webers law

delta I is equal to JND so delta I divided by inital intensity is equal to k (constant)

There is a linear relationship between threshold and

background intensity

What is the absolute threshold of sensation?

The idea of noticing something for the very first time …so the bare minimum amount for your brain to detect a stimulus (50% of the time)… This is basically the line from nothing into something

The absolute threshold of sensation is influenced by

Several psychological states

Explain the psychological state: expectations (ats)

is a psychological state that forms the question are you expecting something …are you expecting your phone to buzz

There are 4 factors that form the signal detection theory (SDT)

expectations, experience, motivations, alertness

What is the signal detection theory

A combination of signal strength

Explain the psychological state: experience (ats)

are you familiar with a stimulus…like your brain will filter out a song or ringtone and be like hey thats my ringtone

Explain the psychological state: motivation (ats)

are you interested in the response of a text? Say you text your crush and you are gradually waiting for a text back your ats would be heightened so that you notice the faintest sound coming out of your phone

Explain the psychological state: alertness (ats)

are you tired and trying to stay awake for a message or are you refreshed and ready to recieve the message? This psychological state dictates mental sharpness

What are subliminal stimuli?

stimuli that are below the absolute threshold of sensation

Somatosensation

The nervous systems process of perceiving external and internal body stimuli

4 types of somatosensation

Thermoception, mechanoreception, nocioreception, proprioception

3 types of somatosensation

The intensity, timing, and location

Thermoreception

a type of somatosensation that has to deal with temperature (ex. testing the bath water)

Mechanoception

a type of somatosensation that has to deal with pressure (ex. running your hand on a burlap sack and feeling the vibrations)

Nociception

a type of somatosensation that has to deal with pain (ex. there is chemical and mechanical noicice…stepping on a leg and lifting your foot)

Proprioception

a type of somatosensation that has to deal with position (ex. knowing your position when walking up the steps in the dark you know to lift your foot up)

Intensity

how quickly neurons fire for us to notice a sensation (meaning that a low intensity is equal to slow, fast=high intensity)

Timing

how neurons understand timing which is broken down into 3 different ways

What are the 3 ways timing is understood

non-adapting, slow adapting, fast adapting

Non-adapting

(doesn’t adapt) neuron consistency fires @ a constant rate and doesn’t change

Slow-adapting

(adapts to a stimulus slowly) neuron fires in beginning of stimulus and calms down after a while

Fast-adapting

(adapts quickly) neuron fires as soon as stimulus starts then stops then starts again onces the stimulus starts

Location

Location stimuli by nerves are sent to brain (which relies on the dermatones)

What are dermatones

Area of skin that sends all of its sensory information to the brain

What is the vestibular system

this is a system that balances sensation across both ears and limbs (balance and spatail orientation) your body’s internal navigation and balance gyroscope, located in the inner ear

What is the Cochlea?

This part of the ear canal (snail shaped) translates sound into nerve impulses that are sent to the brain

What is the Outer ear?

The outer ear contains the tympanic membrane also known as the ear drum

What is the middle ear?

The middle ear contains the oval window which the stapes attach here and the eustachian tube which joins w/ the throat to balance pressure

What are the stapes?

this is the smallest bone in the ear that takes vibrations and amplifies sound in the cochlea (stay-peez)

What is the eustachian tube?

This connects the middle ear directly to your throat which equalizes sound pressure so the system doesnt lock up

What is the inner ear?

These are semicircular canals that balance organs and translate nerve impulse to be sent to the brain

What are the semicircular canals?

The inner ear is the focus!

What is the signal detection theory?

This theory looks @ decisions made under uncertainty and draws between important and unimportant stimuli and also judges at what point we can diferentiate or evaluate a stimuli

Which of these are examples of the signal detection theory?

sonar and the difference between big fish and little fish or on a foggy day the signal of the green ,ight has to be very strong to tell you to go

What are the responses to a signal in the SDT?

Hit, miss, false alarm, correct rejection

What is a hit (SDT)?

Subject responded to affirmative or present signal

What is a miss (SDT)?

Subject responds negatively to the signal

What is a false alarm (SDT?

Subject perceives a signal alarm when there was no signal present

What is a correct rejection (SDT)?

Subject has no stimulus and subject confirms there is no stimulus

what is d’ in the Signal Detection theory?

Strength (when a hit is greater than a miss, there is a strong signal and when the miss is greater than the hit there is a weak signal)

what is c’ in the Signal Detection Theory?

Strategy (there are 2 strategies to reacting to stimulus)

What are the 2 strategies that one uses during the SDT?

conservative and liberal strategy

What is the liberal strategy?

Always saying yes even if you get some false alarms

What is the conservative strategy?

Always saying no unless 100% sure that a stimulus is there and presenting itself

Make sure to review the signal detection theory graph

GRAPHHHHHHHHH

What is bottom up processing?

It begins with a stimulus and influences the data that we percieve

What is top down processing

It begins with what we expect to be there and then we fill in the blanks