Cognition Unit 2

hermann ebbinghaus

hermann ebbinghaus

• Pioneering for memory studies 

• Make up words and then tested his memory on the lists for years 

• Over 6 years memorized thousands of lists

• Found delay between memorization and recall caused forgetting 

• Used many different conditions

• Forgetting curve 

  • Meaningfulness and distinctiveness

    • Meaningful materials are easier to remember 

    • Distinctive or unusual info is easier to retain

      • We’ll remember those thing about people more than the other things they say so that is what they'll think about after first meeting you

types of memory

sensory, short-term/working memory, long term

chunking

creating xx for remembering things 

• Internal coherence with some meaning 

• Order and/or structure are important

cued recall

gives significant hints about the correct answers

• fill in the blank

free recall

simplest but most difficult method of testing memory

recognition

testing memory via identifying from a list

• multiple choice

speaking iconic memory research

• Whole report you could learn much less then the partial report then partial directed 

• When delayed in tone (where they need to look) performance decreased - forgetting curve

information processing model

• Computer has a “buffer” - SM

• RAM (random access memory)  - ST/WM

  • Temporary storage of info

  • Still vulnerable to damage or loss

    • Interference and retention 

• Hard drive - LTM

  • Permanently stored  - relatively permanent storage of mostly meaningful information 

sensory memory store

• Quite large but constricted by brief duration

• Decays rapidly - .3 seconds for visual info and 2 seconds for auditory info

working memory store

• • Limited capacity is limited and duration is about 30 seconds 

    • Lots of variance in our capacities between people and also each person on a given task

  • Often based on sound or speech or even visual inputs 

  • 7 +- 2 so average is 5-9 items

memory store

• 3 stores

• Differ in function, capacity, and duration

• Control processes - control movement of info within and between memory stores

sensory memory

• Initial intake

• Lasts briefly, under half a second

• NEEDS attention

• Combo of memory and perception

• Iconic - visual 

• Echoic - sound 

• Contains everything you are currently perceiving with all your senses - only in the now 

• Typically your attention is focused on some stimuli or set of stimuli in specific 

• Still background processing… filtering

Serial position effect

 if given a list we remember the beginning few and end few 

• Primacy - remembering words at beginning

  • More time to rehearse

• Recency - remembering words at end of list

  • Still in ST/W memory

short term memory

• Can hold a small number of items for 15-30 seconds

• Rehearsal and elaboration

• Temporary storage of recently encountered information

• Central executive 

  • visuospatial sketchpad

  • phonological loop

  • episodic buffer

central executive

Attentional controller that selects and manipulates information

• visuospatial sketchpad

• phonological loop

• episodic buffer

visuospatial sketchpad - ST/W

• used for maintaining and processing visual spatial info

  • Similar to PL but visual info 

  • Limited capacity and must be attended to periodically and rehearsed in order to be preserved 

    • Pointing needs xxx

phonological loop - ST/W

• used to maintain info for short time and for acoustic rehearsal

  • Can keep verbal working memory indefinitely by repeatedly rehearsing 

    • Verbal responses are xxx

episodic buffer - ST/W

• storage for multimodal code, holding an integrated episode between system using different codes 

  • Stores info temporarily and connects to and leverage long term memory

long term memory

• Retrieval and encoding 

• Factors that affect it:

  • How it is encoded 

  • How it is retrieved

  • Context dependence/state dependence

    • Mood dependence

• level of processing

• Spacing effect

• explicit

• implicit

level of processing

• The way we encode it leads to different ability to remember things

• Craik and Lockhart - different ways to process info lead to different strengths of memories 

  • Deep processing 

  • shallow processing

• Craik and Tulving - participants studied a list in three different ways

• Rogers, kuiper and kirker - encoding with respect to oneself increases memory

craik and lockhart - LTM Levels of processing

• different ways to process info lead to different strengths of memories 

• Deep processing 

  • Leads to better memory

  • Elaborating on meaning leads to a strong memory 

• Shallow processing

  • Emphasizing physical features of stimulus

    • The memory trace is fragile and quickly decays 

craik and tulving - LTM LOP

• participants studied a list in three different ways 

  • Structural: is the word in capital letters

  • Phonemic: does the word rhyme with dog

  • Semantic: does the word fit in this sentence “the ____ is delicious”

  • Recognition test was given to see which types of processing led to the best memory

rogers, kuiper and kirker

encoding with respect to oneself increases memory

• more processing when we make connects in learning

tasks and responses in different systems

• Two verbal tasks overloads the phonological loop

• Two visual tasks overload the visual spatial sketchpad system

• The task and response draw on the same WM component results in worse performance than the task and response that are distributed between WM components

spacing effect

practicing something fewer times but more spaced out is more effective than practicing more times in a shorter period of time

explicit - LTM

• Conscious 

• Facts and events that one can consciously know and declare 

  • Hippocampus 

• Episodic memories - memories of personal experiences

• Semantic memories - memories of facts 

implicit

• Unconscious

• Learning an action while one does not know or cannot declare what they know

  • Cerebellum

  • Procedural memory - acquisition of skills as a result of practice

    • Follows a process where a skill is very conceptual/explicit at first 

  • Priming 

• Flashbulb memories 

  • Emotionally loaded memories

    • Emotional strength tends to make memories more retrievable later in general 

    • Not qualitatively different from other types of memory

    • Distinctive BUT they show some forgetting 

    • Incorrect info can come from a number of sources And become part of the memory

    • People hold this sort of info for longer than normal memories 

  • Not complete, not immune to forgetting, and can be grossly inaccurate 

  • People are more confident in how they remember them than everyday memories 

why we forget

• Catastrophic loss of memory can only result from brain damage or disease 

• Anterograde amnesia - short term memory loss - issues with encoding of short/working memory into long term 

• Remembering everything would be overwhelming and debilitating 

• Many times with brain damage people lose one type of memory but retain other types 

• Hippocampus - integration and consolidation

  • Declarative memory

  • Without it, only learning of skills and habits

HM Case

in 1953 he had his hippocampus and surrounding areas of the temporal lobes removed

• Got rid of his seizures but memory impairment was severe - could not form new memories - explicit memory/info issues

• Learned he could do working memory or sensory but not long term memory 

• The more difficult a memory task the more it depends on the proper functioning of the hippocampus - he could do procedural memory

• No ability to recall words but could recognize them - ability half of controls - or just because he has a 50% chance of getting it correct

encoding failure

seen keyboards hundreds if not thousands of time

• Never attended to one closely enough to encode all of its specific features 

• Not encoded into LTM

Daniel Schacter

said we distort or forget memories 

• Sins of omission - forgetting

• sins of commission - distortion

sins of omission - daniel schacter

• Transience

• Absentmindedness

• Blocking/interference

  • retroactive interference

  • proactive interference

sins of commission - daniel schacter

• Misattribution

• Suggestibility

• Bias

  • Barlett’s study

• persistence

• Hippocampus - convergence zone

  • events are pre processed or filtered before reaching the hippocampus

  • Some of this filtering in prefrontal cortex - understanding meaning of info or occipital lobe

  • same activity whether the memory is true or fales

Transience - sins of omission

• Forgetting that occurs with the passage of time

• Basic feature of memory and the culprit in many memory problems

• Can sometimes leave us feeling embarrassed - forgetting someone's name

absentmindedness - sins of omission

• Not focus on what we need to remember

• Desired info isn't lost over time - either never registered or not sought to after the moment it is needed because attention is focused elsewhere

blocking/interference - sins of omission

• Forgetting that occurs when one memory competes with another memory

  • Retroactive interference

    • Learning the new info will block the old

  • Proactive interference 

    • Prior knowledge of old block the learning of new

    • Saying out loves name with new flame in same restaurant 

• If you sleep right after your last study session instead of staying awake it helps reduce interference and you will remember more

suggestibility - Sins of commission

• Leading questions

• How fast were cars going when smashed v bumped - the framing changed their responses after watching the same videos

DRM paradigm

false memories - words not in list but highly associated with the words listed 

• Target or lure word  or target

• Recall that critical/target/lure word and are often confident it was on the list 

• Remember an event and start with details you remember clearly and fill in gaps - reconstruction

false memory narrative study

• Contact parents about events in childhood

• Create packet for participants with 3 true events and 1 false 

• Criteria - kids had diaries and got consent from parents 

• Events like lost in mall, spill punch bowl, hospitalization, birthday part with clowns

• 3 interviews 

• First interview remember most of the true events and don't recall the false events 

• By the third interview remember true events more and 25% recall the FALSE events

how are false memories created

• Plausibility

• Source monitoring judgements - murky if it really happened

source attribution

decide if representation has external v internal origins

False memories tend to be…

shorter and less detailed but not always

misinformation effect

false memories can invade memories when:

• We talk to other people (remembering shared experiences differently)

• We are suggestively interrogated (law officers, psychotherapy)

• We read/view media coverage

imagination inflation

source confusion

• Imagination makes events more familiar

Biases in eyewitness testimony

• Suggestive questions 

  • Witnesses incorporate misleading info into their memories

• Retelling

  • Adjust story to please listeners because they can’t remember details 

• Post event info

  • Testimony often reflect not only what they saw but later obtained info

• Kids are very impressionable

• Assumption that perpetrator is in lineup - distractor selection is important and police behavior may also influence eyewitness

concepts

mental grouping of similar objects, events, ideas, etc

• Formation of categories or concepts primary way to organize information

• Several ways to categorize..

• Help to understand individual cases not previously encountered

• “Pointers” to knowledge

  • Provide a wealth of general information about the item

• Form some concepts with definitions 

  • Triangle as three sides 

  • Then mental images or prototypes

  • Robin is a prototypical bird but penguin is not 

prototype

• an average representation of the “typical” member of a category

• An average of category members encountered in the past 

• often a mixture of “typical” examples

Typicality effect

Whether a prototypical member belongs to a category -> more quick answers than a non-prototypical member

Rosch’s priming experiment

• LTM experiment 

• Priming procedure 

  • Present stimulus that facilitates the response to another stimulus  

• Prototypical members of a category are more affected by priming 

• “Green” prototype matches the good green (a) but is a poor match for the light green (b)

Exemplar approach

• The more similar a specific exemplar is to a known category member, the faster it will be categorized (family resemblance effect)

• Difference from prototype view

  • Representation is not abstract

  • Descriptions of specific examples

Hierarchical categorization

difficult to think about something by itself

• Many things belong to different categories at different levels  

• Objects are typically understood under categories 

• Global, basic, specific 

  • Basic has far more info than global

  • Very familiar material tends to be categorized at the specific level

Semantic connections of knowledge

knowledge is not just hierarchies they are also connections 

• Collins and quillian's model

• Cognitive economy - shared properties are only stored at higher level nodes 

• Nodes represent concepts in memory

• Critics:

  • Predictive and explanatory of some results, but not all

  • Lack of falsifiability - no rule for determining link length or how long activation will spread

  • circular reasoning

Spreading activation networks

• Concepts are connected hierarchically and are connected to what they are related to by personal experiences

• Activation is the arousal level of a node and when the node is activated activity spreads out

• concepts that receive activation are primed and more easily accessed from memory

• reaction time was faster for closely associated pairs

fan effect

 there is a nonlinear relationship between how much you know about a topic and how fast you can answer questions about it 

• If you have little knowledge there is less knowledge to sift through it so you respond quickly

• If you have a lot of knowledge on a topic it is organized and also leads to a quick response 

• When you think of a concept to answer a question a certain amount of cog activation occurs and it is divided between all the connections that concept has

  • More connections and less activation and thus takes longer to remember

    • The activation” fans out”

connectionist network

• Much more complicated model

• Creating computer models for representing cognitive processes

• Potential actions through hidden “relationship nodes” with different weights 

  • Weights determine at each connection how strongly an incoming signal will activate next unit

• Suggests “neuron-like units” 

  • Input: activation by stimulation from environment

  • Hidden units: receive input from input units

  • Output units: receive input from hidden units

• Criticism:

  • Neglects properties of neural systems

  • Lots of aspects that aren’t well defined