MEMORY

• What is capacity?

  The amount of information that can be held in a memory store
• What is duration?

  The length of time information can be held in memory
• What is coding?

  The format in which information is stored in the various memory stores.
• What are the three types of coding?

  Acoustic-sound

  Visual-looks

  Semantic-meaning
• What is the sensory memory/register?

  -stores for each of our 5 senses such as vision(ionic) and hearing(echoic)

  -capacity is huge

  -information lasts here for approximately a millisecond
• What is the short term memory?

  -the limited capacity memory store for immediate events

  -coding is mainly acoustic(sounds)

  -capacity 5-9 items

  -duration 18-30 seconds
• What is long term memory?


  -permanent memory store for events happened in last

  -coding is semantic

  -unlimited capacity

  -duration is up to a life time
• What is the multi-store model?

  1. Environmental stimuli

  2Attention needed for it to be in sensory register

  3. Can be stored as echoic,ionic or other sensory stores

  4. Information can be lost due to very limited duration

  5. Or can be transferred to STM where it's retrieved or forgot

  6. Maintenance rehearsal leads to prolonged rehearsal

  7. Then stored in LTM where it can either be forgot or retrieved in STM
• What is the capacity,duration and coding for the sensory register?

  Capacity-very large

  Duration-milliseconds

  Coding-depends in organ involved
• What is the capacity,duration and coding for the STM?

  Capacity-5-9 items

  Duration-seconds

  Coding-acoustic
• What is the capacity,duration and coding for the LTM?

  Capacity-unlimited

  Duration-up to a life time

  Coding-semantic
• What are they key details about the MSM?

  .sensory memory has several sensory registers that deal with information from a particular sense:

  -ionic register (vision)

  -echoic register(sound)

  -haptic register(touch)

  
  

  .only if attention is focused on one of the sensory stores will data be transferred to STM

  
  

  .in STM maintenance reversal is used and if you don't rehearse you won't remember. Rehearsal eventually created a long term memory.

  
  

  .in STM new information can displace original information due to STMS limited capacity
• Evaluation the MSM-research into the capacity of STM

  - digit span technique is a good way of testing STM capacity

  -jacobs used this to assess capacity of STM in a lab

  -he found average recall for digits was 9.3 items and 7.3 for letters
• Evaluation of the MSM-research into the capacity of STM

  -George Miller

  -he reviewed psychologists work and concluded the duration of STM is about 7 items

  -he called this the 7+ or -2 magic number

  - he said we can't chunk items together to remember more
• How do these studies support the MSM?

  - they support that the capacity of STM is 5-9 items
• Evaluation of the studies

  . The size of the chunk matters

  -Simon found people had a shorter memory for larger chunks like 8 word phrases compared to smaller chunks such as one syllable word

  
  

  . Individual differences

  -capacity of STM not the sane for everyone

  -digit span seems to increase with age

  
  

  . Methodological evaluation

  -ve lacks ecological validity (artificial setting)

  -ve lacks mundane realism (task is artificial)

  +ve scientific method

  +ve reduced extraneous variables
• What is some research into the duration of STM?

  Margaret & Lloyd Peterson conducted a study into the duration of STM using 24 American university students:

  
  

  Procedure:

  .each pt tested over 8 trials

  .each trial pt was given trigram to remember and 3 digit number

  .has to count backwards from 3 digit number for a period between 3&18 secs

  .then had to recall diagram.

  
  

  Findings:

  .90% correct with retention interval of 3 secs

  .20% correct at 9 seconds

  .2% correct at 18 seconds
• How did these findings support the MSM?


  Suggests the duration of STM is seconds
• Outline what the graph did retention interval(seconds) and percentage correct shows

  .longer time=less remembered
• Evaluation of study?

  -be pts counted backwards to prevent rehearsal however numbers could've displaced trigram

  -displacement could be reason they forgot trigram and not decay over time

  -meaning study may not have measured duration of STM
• Other evaluation

  -ve lacks ecological validity

  -ve didn't test a wide range of pts (24 Americans)

  -ve artifical

  -ve lacking realism

  -ve biased sample

  +ve scientific methods

  +ve lab reduces variables
• What is the research into the duration of STM?

  - bahrick et Al tested 400 people between ages 17-74 on their memory of classmates

  - photo recognition test of 50 photos some of classmates and others not

  -recall tested in 4 different ways:

  .free recall (as many names they could remember)

  .photo recognition (identify classmates)

  .name recognition test

  .name and photo matching test

  
  

  Finding:

  . 90% of participants able to correctly match names and faces 14 years after graduating

  . 60% of participants able to correctly match names and faces 47 years after graduating

  
  

  -Bahrick concluded most people could remember information like faces and names for almost a lifetime

  -supports MSM and idea LTM has lifetime duration and is semantically coded
• Evaluation of study

  -big sample size (400)

  -variety of ages

  -mundane realism
• What is the research into the capacity of LTM

  -solomon shereshevsky

  . Memorised a lot in a few minutes accurately

  .diagnose with synaesthesia so all senses used for 1 object

  . Numbers, words and nonsense syllables all recalled perfectly no matter how much given to him

  . Memory caused him to struggle to focus as all his sense would fire at once

  . Super auto biological memory
• What is research to show the coding of STM & LTM?

  Baddeley

  
  

  Procedure:

  -used words to test encoding of STM and LTM

  -to test STM he used a list of words that sounded acoustically similar and words sounding acoustically different

  -to test LTM he used words that were semantically similar and a list semantically different

  
  

  Findings:

  .he found when testing STM pts had difficulty remembering acoustically similar list-this us because STM codes words acoustically and when they sound the same it gets mixed up

  
  

  .he found when testing LTM pts they had difficulty remembering semantically similar list- LTM was trying to code words semantically and got mixed up as words meant same thing
• Evaluation of study

  +ve scientific method

  -ve lacks ecological validity

  -ve lacks mundane realism
• What do Baddeley's results show us about coding in STM & LTM?

  -shows us that STM codes acoustically and LTM code's semantically. And words that are acoustically/semantically similar get mixed up
• What happened to HM?

  -underwent brain surgery to relieve epilepsy

  -his hippocampus which is central to memory function was accidentally removed

  -he thought he was 27 when he was 31

  -he had little recall of the operation and couldn't remember speaking to someone an hour earlier

  -his LTM never improved with practice and couldn't recall what he ate in a day

  - he performed well on tests for immediate memory recall
• The case of HM is usually taken ti support the MSM. Can you explain why?

  Supports that STM and LTM are separate stores.
• What happened to Clive Wearing?

  -worst case of amnesia

  -only recognises wife

  -less than 30 secs memory

  -forgets previous sentence

  -doesn't remember flavours

  -keeps thinking he's just awaken from consciousness

  -has no past/idea of future

  -remembers how to play piano

  -had virus

  -his STM doesn't work

  -has LTM partially
• How does Clive's case support the MSM?

  - supports separate stores

  -retrieval? Why can he recall some LTM memories
• General evaluation of the MSM

  +ve there is lots of supporting studies to jack up the MSM

  
  

  +ve case studies I'd patients support distinction between STM and LTM in MSM eg Clive (LTM intact but STM defective)

  
  

  +ve studies using brain scanning technique have found prefrontal cortex is active when doing STM tasks and hippocampus is active doing LTM tasks

  
  

  -ve the MSM is too simple there is more than 1 type of STM & LTM

  WMM suggests STM is divided into multiple components

  KF better at visual STM than auditory STM

  
  

  -ve oversimplifies LTM

  LTM not one store

  We have 1 store for memories and a different store for learned skills like riding a bike

  Model is limited as doesn't explain this
• What are the types of LTM?

  1. Episodic Memory

  -personal events like daily diary of events

  -includes when events occurred,people,objects,places and behaviours

  -have to be retrieved with effort and time stamped

  -examples: birthday party,dentist visit,starting university

  
  

  
  

  2. Semantic Memory

  -for our knowledge of the world

  -facts/knowledge of words/concepts

  -need to be recalled deliberately

  -not time stamped

  -examples: taste,capital

  
  

  3. Procedural Memory

  - for our knowledge of how to do things/stores learned skills

  -includes memories of learned skills

  -recall without making effort

  -examples: riding a bike, making a cup of tea
• Evaluation of different types of LTM

  . Brain scan evidence

  - Tulvig for participants to perform memory tasks whilst brains were scanned using PET scanner

  -episodic and semantic memories recalled from prefrontal cortex

  -left prefrontal cortex=semantic memories

  -right prefrontal cortex=episodic memories

  -procedural memory =cerebellum

  shows physical reality if types of LTM in brain= validity

  
  

  .A limitation is that there are problems with clinical evidence

  -evidence for case studies on LTM often come after brain has been damaged

  - lack of control of different variables in studies like personality or area of damage

  - difficult to generalise studies and determine exact nature of LTM

  
  

  . Real life application

  -psychologists can target certain kinds of memory to improve peoples lives

  -belleville et al , episodic memories could be improved in older people who has a mild cognitive impairment

  training led to improvements compared to control group

  beneficial to distinguish between types of LTM so treatment can be improved

  
  

  
  

  . Supported by case study evidence

  - HM and Clive Wearing

  - both had severely impaired episodic memory

  - but semantic memories were okay and procedural

  - eg HM didn't remember striking a dog an hour earlier but still understood concept of fog

  - supports distinction of separate stores as 1 can be damaged and the other one okay
• What is the working memory model?

  - baddeley and hitch developed the wmm

  - model just focuses on STM

  - more than one type of STM

  - model consists of 4 main components:

  . Central Executive

  . Phonological loop (PL)

  -articulatory process

  -phonological store

  . Long-term memory

  . Visuo-Spatial Sketchpad (VSS)
• Details about each component of the WMM

  1. Central Executive (BOSS)

  - overall control of other 3 slave systems

  -directs attention to particular task and monitors incoming data

  - makes decisions and locates data to each slave system depending on type

  -limited capacity can't attend to too many things at once and has no capacity did storing info/data

  
  

  2. Phonological Loop

  -deals with auditory info & preserves order in which information arrives

  - has limited capacity & coding is acoustic

  - sub-divided into:

  . The phonological store: passive store of words you hear-inner ear

  . The articulatory process: active rehearsal system and allows maintenance rehearsal of sounds/words

  Capacity 2 secs

  
  

  
  

  3. Visuo spatial sketchpad

  - stores visual & spatial info like how many windows in a room

  - visual info: what things look like

  - spatial info: relationship between things

  - capacity: 3-4 objects

  Subdivided into:

  - visual cache: stores visual data (structure/colour)

  - inner scribe: records arrangement of objects in visual field

  
  

  4. Episodic Buffer

  - added later to original model

  - temporary store for info verbal/visual/spatial

  - integrates indie from CE, VSS,PL

  - maintains sense of time sequencing- recording events

  -sends info to LTM
• Evaluation of WMM Dual Task Performance


  . Support from separate components

  - Hitch and Baddeley dual task study

  - pts given 2 tasks to do simultaneously

  - all pts had t complete task 1 using central executive

  - task 2 used phonological loop or phonological loop & CE

  - control group did no second task

  . Task 1= A is followed by B in AB

  . Task 2( using articulatory loop)= saying the the the over and over again

  .Task 2 ( using articulatory loop& CE)= saying random digits

  Resulrs

  Group 1

  Task 1 CE

  Task 2 PL

  Results: Task 1 = same speed

  
  

  Group 2

  Task 1 CE

  Task 2 CE&PL

  Results: Task 1= slower

  
  

  Group 3

  Task 1 CE

  Task 2 NO TASK

  Results: Task 1= same speed

  
  

  What do results suggest about separate components and WMM?

  Supports WMM

  - shows CE can't attend to too many tasks

  -2 tasks with CE did worse

  - shows different components exist different results depend on component used

  
  

  Evaluation of study

  -ve lacks mundane realism (lab based)

  -ve lacks ecological validity

  +ve scientific method

  +ve no extraneous variables
• What are the case studies of KF, SC , LH

  KF

  -had an accused

  - forgot more auditory than visual

  - auditory problems limited to verbal material like letters and digits but not meaningful sounds

  - brain damage limited to phonological loop

  
  

  SC

  -good learning abilities

  -unable to learn word pairs presented out loud

  -suggests damage to phonological loop

  
  

  LH

  -involved in a road traffic accident

  -performed better on spatial tasks than those involving visual imagery

  -suggests separate visual and spatial systems
• How do these case studies support the WMM?

  -supports stores are separate as different parts of WMM affected.
• Evaluation continued of WMM

  .There is some concern over the CE-what exactly is it?

  -allocates resources and essentially same as attention

  -some psychologists think its too vague and doesn't explain anything

  -baddeley said that CE is most important but least understood part of WMM

  
  

  .Critics also feel the notion of a single CE is wrong and that there are probably several components within it

  -Eslinger and Dmasio (1985)-EVR case study

  -EVR could do reasoning tasks but not decision making

  -CE does both things so why can he only do 1?

  -Idea of 1 CE too simple

  
  

  .Braver et al (1997)

  -gave pts tasks involving CE whilst having a brain scan

  -found greater activity in prefrontal cortex

  -activity in area increased with task difficulty

  -makes sense in terms of WMM as CE has to work harder to fulfill its function.

  
  

  .Validity of the model?

  -dual task study supports WMM as it shows separate components

  -studies are highly controlled and not normal everyday memory tasks

  -challenges validity of model as its not certain working memory operates this way in everyday situations