Sensory Processing Flashcards
What is bottom up processing? How is it different from top down processing. Give an example of each
Bottom up processing is when a stimulus influences our perception. This type of processing occurs when we experience something for the first time or when we encounter something unfamiliar.
Ex. A student who isn’t a biology major sees an amino acid. They may recognize that it’s a molecule or related to science but not necessarily what it is/does.
Top down processing is when our background knowledge influences our perception. This occurs when we are familiar with the stimulus
Ex. Finding your spouse in a crowd. We can correctly identify our husband/wife because we know what they look like. If not we would just be looking into a sea of people
What would happen if the Gestalt Principle-Law of similarity was not true?
The law of similarity states that your brain groups items that are similar together. Without this function, you would not be able to recognize patterns, organize shapes or items (i.e. pairs of socks), or basically sort any objects
What is the Gestalt Principle Law of Pragnanz? How would our brain function differently if the Law of Pragnanz didn’t exist
The Law of Pragnanz states that our brain reduces reality to it’s simplest form. If this was not the case, we would not be able to process information as quickly. We would take longer to process an image because our brain is processing more complicated shapes instead of the simplest shape. I.e. looking at the Olympic Rings
What is the gestalt principle law of proximity?
We group objects together that are closer to each other
What is the gestalt principle law of continuity
Lines are seen following the smoothest path
What is the gestalt principle law of closure
Objects that are grouped together are seen as a whole
What is a sensory threshold?
The minimum amount of stimulus needed to cause a change in perception.
What is absolute threshold?
Minimum stimulus needed to activate a sensory system. This the minimum intensity at which an action potential will occur and be detected 50% of the time.
What is the threshold of conscious perception?
Also known as subliminal perception, it’s a stimulus that causes an action potential but not one strong enough to cause conscious perception (awareness)
What is the difference threshold and how is it related to Weber’s Law?
Minimum difference in magnitude between two stimuli before you can tell the difference.
Weber’s law says the ratio between the change in stimulus and it’s original value is constant no matter what the values are. ∆I/I=K where ∆I is stImulus 1-stimulus 2/ stimulus 1.
Lil Webbies law- the ratios are independent of the values 😅
Signal detection theory
Perception is influenced by sensory and non sensory factors. I.e. how bright how loud etc. or memory, motives and expectations.
Our detection can be categorized by hits (we correctly detect the signal) misses (the signal was there but we missed it) false alarms (we thought the signal was there but it won’t.) and correct negatives (the signal wasn’t there and we perceived it wasn’t there.)
Sensory adaptation
The detection of a stimulus changes over time. For example we go nose blind to smells (perception adaptation) or when our pupil dilate in a dark room (sensory adaptation)
