Cognition Midterm

sensation

basic process of interacting with the world around you, turning sensory stimuli into electrical signals to the brain

sensory receptors

detect; stimuli in the outside world trigger sensory cells to activate

transduction

occurs at the receptor site; the point where a sensory stimulus is translated into an electrical impulse

sensory pathway

relay; nerves carry “info from sensory receptors” (Action potentials) to the brain

sensory processing

interpret; an area of the brain interprets info from receptors into what we perceive as reality

absolute threshold

stimulation required for detecting a stimulus 50% of the time

subliminal threshold

below the 50%; stimuli that require more interpretation (think subliminal messages)

difference threshold (just noticeable threshold)

change in stimulation required for detecting said change 50% of the time

weber’s law

bigger stimuli need larger differences to be noticed; you’re more likely to notice a change in a small stimulus but it takes more to notice the difference in a large stimulus

EX: you’re more likely to notice the difference in a 1lb weight and a 2lb weight than the difference in a 101lb weight and a 102lb weight

habituation

higher processes suppress higher processing of certain sensory information; reduced response to a repeated stimulus that used to elicit a strong response

EX: no longer feeling the weight of wearing a sweatshirt after putting it no multiple times OR you neighbor’s door used to cause you to jump but the more you hear it the more used to it you get and no longer jump

sensory adaptation

sensory receptors acclimate to constant/repeated stimuli; the nerves change the way they fire to adjust to the stimulus and occurs automatically

EX: when you first get into a pool it’s freezing cold but you eventually warm up to it OR smokers not being bothered by the smell of tobacco smoke the way nonsmokers are

taste

processing in the insular cortex; these cells are the receptors (salty, sweet, sour, bitter, umami)

touch

processing in the postcentral gyrus

• thermoreceptors (heat)

• nociceptors (itch)

• puriceptors (pain)

• mechanoreceptors (pressure)

• proprioceptors (location)

smell

processing in the medial temporal lobe; olfactory cells are the receptors

sound

processing in the superior temporal gyrus; hair cells in the organ of corti in the cochlea are the receptors

vision

processing in the occipital lobes; cones and rods are the receptors

sensory memory

the capacity for briefly retaining large amounts of information that people encounter daily; includes information from every sense

sperling tests of iconic sensory memory

immediately after the sensation disappears, almost all sensory information remains available and almost all of that information disappears within seconds

• whole report

• partial report

• delayed partial report

selective attention

focused on one task

divided attention

paying attention to multiple stimuli; purposefully paying attention to two things at once

distraction

focused on one task interfered with by other stimuli

attentional capture

a rapid shift of attention to an especially salient stimulus

salient stimulus

something that calls your attention and sticks out in its environment

EX: a cow walking into the classroom

Filter in the Filter Model of Attention

attends to certain information in sensory memory (which holds only raw, basic information) based on raw, basic info (sensory channel, pitch, color, speed, etc.) and passes that information to the detector

EX: attending to a certain voice based on its pitch or ear of origin

Messages in the Filter Model of Attention

raw low-level sensory information going into sensory memory and then the filter

Detector in the Filter Model of Attention

processes higher-level info about info (meaning); passes info to short-term memory; higher processing occurs to all of the information that passes through the detector

How does the filter model of attention work?

if there is an auditory stimulus going into our right and left ear then the filter will shut off the auditory stimulus going into the right ear and send the auditory information from the left ear to the detector for high-level processing

EX: If two people are talking, one talks low and the other one talks loud then we focus on the guy talking low and filter out everything else that is high-pitch

Problem with the filter model of attention

everything not sent to the detector isn’t higher processed is not true, some things slip through things that we are trying to filter; if this model was correct then we would have no idea what we were hearing besides what we were attending to

EX: Cocktail party – being at a party and then suddenly hearing your name, even though you were filtering out everything that wasn’t at a certain pitch and your name wasn’t at that pitch

dichotic listening task

headphones are given to the participants with two different things playing in each ear, the participant is told to focus on only one side but once asked if they knew what was playing in the other ear they said yes; example of problem with filter model

dear aunt jane experiment

even when information switches ears during a dichotic listening task, people still keep track of what they’re not supposed to pay attention to; an example of a problem with the filter model

Attenuator of the Attenuation Model of Attention

decides what information is attended to and what is not based on physical characteristics, language, and meaning

Dictionary Unit of the Attenuation Model of Attention

contains all of the words you know and their thresholds which influence if the words are attended to

EX: your name has a very low threshold because it takes very little activation (affected by loudness, occlusion by noise, etc.) for us to attend to it but the word has a high threshold which means very high activation is required for us to attend to it HOWEVER this threshold differs person to person and is very malleable

Unattended Messages of the Attenuation Model of Attention

 information that “leaks” through (hence leaky faucet); most of this information ends at the dictionary unit but words with low thresholds may get through to short-term memory

Attended Messages

goes through to short-term memory

processing capacity

amount of information an organism can process; the amount of information we can pay attention to at a given time

perceptual load

task difficulty; how much of our attention needs to be attended to a task

EX: studying for an exam is high load while talking on the phone is low load

salience maps

information in your environment that calls your attention

priority maps

information in your environment that you want to attend to

Frontoparietal Attentional Network

purpose is to focus our attention on certain sensory information and it is a distributed network

Regions:

• visual cortex

• posterior parietal cortex

• frontal eye fields

• midbrain

• prefrontal cortex

visual cortex of the frontoparietal attentional network

builds feature maps of our environment based on the attending stimuli; feature maps are made of feature detectors (our senses); talks with posterior parietal cortex

posterior parietal cortex of the frontoparietal attentional network

sets salience and priority maps and shifts our attention; talks with the midbrain, visual cortex and the frontal eye fields

frontal eye fields of the frontoparietal attentional network

plans eye movements based on PPC; works with PPC to set priority maps based on the prefrontal cortex; talks with the posterior parietal cortex, visual cortex, and the midbrain

midbrain of the frontoparietal attentional network

tells the eye muscles to perform the eye saccades (eye flips from one stimulus to another)

prefrontal cortex of the frontoparietal attentional network

sets/maintains attentional goals/priorities; talks with the frontal eye fields

simultagnosia

unable to process/pay attention to more than one thing at a time; this occurs when your frontoparietal attention network can’t consciously set what to pay attention to  

default mode network

when certain regions still show above-average activity when “mindless”, so the brain defaults to these regions; fMRI best shows this

sentinel hypothesis (default network)

“watching out”; broadly monitoring the environment and keeping an eye out for important (highly salient) stimuli; waiting for something important to wake you up so you can respond to it

internal mentation hypothesis (default network)

“mind wandering”; mindlessly tying past experiences to new stimuli; adding meaning to events you’re experiencing; checks you out to form new memories

short-term memory

system involved in storing small amounts of information for a brief period of time; bucket of attended info

working memory

a limited capacity for temporary storage and manipulation of information for complex tasks; using the attended info in the basket

key features of short term memory

capacity: 5-9 pieces of information

duration: 15-20 seconds

error: decay

digit span task

repeat a sequence of numbers but as the task goes on, the sequence of numbers increases; people typically aren’t able to remember sequences longer than 9 numbers; measures short term memory capacity

brown peterson task

measures the duration of short-term memory; hold a 3 letter span + manipulation number information, the researcher shows you three random letters and then asks you to count down by threes from a random number from 3-18 seconds; as time increases, our retention of information decreases

chunking

a collection of elements that are strongly associated with one another but are weakly associated with elements in other chunks; leads to more space in short-term memory

pattern

a type of chunking; grouping things based on sequence

EX: in a sequence of ABCXYZNOP we would group “ABC” “XYZ” “NOP”

category

grouping things by meaning/semantic associations

EX: a grocery list with ham, turkey, beef, cheese, and yogurt we would group all of the meats and all of the dairy together

Baddley’s Model of Working Memory

• phonological loop

• episodic buffer

• visuo-spatial sketch pad

• central executive

phonological loop

auditory; the phonological store; small bucket for briefly holding auditory information (like words) but the space depends on word length; contains articulatory rehearsal process and articulatory suppression

articulatory rehearsal process

skill for keeping items in phonological store from decaying; saying it over and over again

articulatory suppression

trying to remember something in the phonological store and then talking to someone, it affects our ability to remember words; producing unrelated sounds is articulatory suppression

episodic buffer

extra capacity for working memory; can hold any kind of information and communicate with the long-term memory

visuo-spatial sketch pad

visual, spatial, haptic/touch; holds and manipulates visual/spatial information; involved in the creation of visual images in the mind in the absence of a physical visual stimulus

central executive

attention controller; maintaining or changing goal-directed behavior

letter-number sequence task

manipulate the auditory information in short-term memory using working memory; the tasks is giving the participant a sequence of letters and numbers and then asking them to rearrange it alphabetically and numerically

spatial reasoning task

manipulate the visual information in short-term memory using working memory; “imagine what a thing would look like if you did xyz to it”

central executive in baddeley’s model

the output is directed by working memory which is overseen by central executive (output is speaking out loud to rehearse something; producing something from short-term memory)

central executive in broadbent model

it oversees the goal-setting/maintenance of what the filter is paying attention to

central executive in treisman model

it oversees the goal-setting/maintenance of what the attenuator is set to pay attention to, potentially also with setting thresholds in the dictionary unit

activity dependent working memory

constant, specific, higher-level firing briefly continues to represent no-longer-present stimulus (aka storage that you can use); prefrontal cortex activity represents attended info in STM/WM

activity silent working memory

cluster of briefly strongly connected neurons continues to represent no-longer-present stimulus; increased connectivity within a neural network represents info in STM/WM

long-term memory

a relatively permanent information storage system that enables one to retain, retrieve, and make use of skills and knowledge hours, weeks, or even years after they were originally learned

1. Lasts days to years

2. Capacity: infinite

3. Stores information not currently holding your attention and must be recalled for use

explicit memory (declarative)

facts and events; memories that you can declare

episodic memory

events

EX: your birthday party

semantic memory

facts

EX: where the library is, when the Great Library of Alexandria burned

implicit memory

procedural; muscle memory, conditioning; memories that must be implied from actions; hard to be stated with words but with actions can be implied

EX: playing a song you learned on the piano; bicycling to the library

retrieval

pulling information from long-term memory to short-term memory

consolidation

information from short-term memory into long-term memory; may consolidate information that you rehearse, repeat, or pay particular attention to; it’s like taking notes on a lecture and then putting those notes in a filing cabinet for later; behaviors to consolidate: flashcards, practicing, focusing hard on a conversation

depth of processing

influences consolidation; while info is in STM/WM; processing level/type of rehearsal matters; shallow < deep

shallow processing

little attention to meaning; tying information to no meaning, very raw information and leads to weak long-term memories

deep processing

attention to meaning, using association/relation

maintenance rehearsal

rehearsing something and paying no attention to its meaning aka articulatory rehearsal process of phonological loop

EX: trying to remember someone’s pone number  and just saying the number over and over

elaborative rehearsal

rehearsing something and focusing on paying attention to its meaning and using association to help them with rehearsal

adaptiveness

forming better long term memories because they relate to our survival

testing effect, Karpicke and Roediger

enhanced performance due to retrieval practice, practice to retrieve the information, and effortful recall of new memories improves retention; students studied pairs of English and Swahili words and then took a test on them; the groups that studied all pairs and took tests on all pairs and groups that only studied pairs incorrectly remembered and tested on all pairs had the best performance grades

spacing

given too much information at once leads to poor consolidation; sleeping is key for spacing to occur

EX: trying to cram the night before an exam

intrusion

adding new information; only occurs in sensory and short-term memory

decay

loss of information

Filing Cabinet Example of Intrusion and Decay

the notes in the filing cabinet are in long-term memory, while in the filing cabinet, they can start to fray and get old (decay) but pulling the notes out (retrieval/short-term memory) and writing on them (intrusion) and then putting them back in the filing cabinet (long term memory); you can’t write or add new information to notes that are in the filing cabinet (long term memory), you have to retrieve them (bring them to short term memory)

synaptic consolidation

changes in the neuronal level that solidify new long-term memories; structural changes at the synapse of a neuron; neuron A and neuron B change the way they talk to each other after an event; changes at the synapse in both neurons that help them to increase communication

long term potentiation

part of synaptic consolidation; aka Hebbian plasticity; “fire together, wire together”; presynaptic has a stronger influence on postsynaptic after intense or repeated signaling because of physical changes at synapses in neurons

potentiation

strengthens the effect of neuron A on neuron B based on their activity from an event

systems consolidation

who is talking to who; changes at the circuitry level that solidify new long-term memories; forming cell assemblies via hippocampal activity and each part of the cell assembly represents a different aspect of a piece of info/event; cell assemblies are tied together via the hippocampus

result: a group of neurons with strong connections that often fire together

models of consolidation

hippocampi (located in the medial temporal lobe) tie together areas that were active during a stimulus to form new memories together

standard model of consolidation

the areas of the brain are activated due to a stimulus, the hippocampus then reactivates all of those areas together causing them to build a cell assembly and form connections and then it stops; says the hippocampus will purge its connections once the assembly is formed – the memory now lives entirely in the original area of activation

multiple trace theory

the hippocampus does not disengage after the cell assembly is built, according to this theory it continues to build connections and memories; the hippocampus will keep its connections even after the assembly is formed – it can recall the memory and/or add to it itself

• Stimulus -> many areas active (processing it) -> hippocampus reactivates those areas over minutes, hours, days afterward -> areas not form cell assembly (cell assembly = consolidated memory)

behavioral data

measurable actions as proxy for internal processes

• response time

• accuracy

• choice

psychophysiological

physiological responses as proxy for internal processes; focus on autonomic nervous system responses; tells us about change in cognitive processes during a task

examples of physiological data

• skin conductance

• cardiovascular activity

• pupil diameter

• reflexive movements

examples of behavioral data

• switch costs

• stroop effect

  • mirror drawing task

neuroimaging

neural activity as proxy for internal processes; producing scans/images of the brain and/or its activity