Memory - x

• Coding - Baddeley


  Tested immediate recall and recall after 20 minutes.

  He used 4 groups - acoustically similar, dissimilar, and semantically similar, dissimilar

  Recall done after the task was worse for acoustically similar words

  Recall after 20 minutes was worse for semantically similar words.

  STM = acoustic

  LTM = semantic
• Capacity - digit span - Jacobs


  The researcher read out 4 digits and ppts were to recall out loud.

  If correct, the researcher would then read 5 words and ppts would recall, and so on.

  Mean digit span for all ppts was 9.3 items

  for letters = 7.3
• Capacity - Miller


  Made observations in everyday practices.

  Made note that things come in 7's: 7 days of the week, 7 deadly sins, etc

  Thought capacity of STM = 7+/-2
• Chunking


  Grouping sets of digits or letters into units/chunks
• Duration of STM- Peterson and Peterson


  Peterson and Peterson - tested 24 ppts in 8 trials

  Each ppts is given a consonant sylabul to remember (e.g. XYZ).

  ppts had to countdown from a number to prevent rehearsal

  on each trial ppts were told to stop after various amounts of time: 3, 6, 9, 12, 15, and 18 seconds.

  after 3 seconds recall was 80%

  after 18 seconds recall was 3%

  Suggested duration of STM was 18 seconds unless rehearsed.
• Duration of LTM - Bahrick et al


  Bahrick et al - high school photo memory test

  392 American ppts

  2 types of recall test:

  - photo recognition

  - free recall - ppts recall the names of ppl in their class

  ppts who were tested 15 yrs after graduation = 90% accuracy on photo recognition

  after 48 yrs = 78%

  for free recall - tested after 15 yrs of graduation = 60%

  48 yrs = 30%
• 3 stores in MSM


  Sensory register, STM, LTM
• Names of several registers in the sensory register

  Iconic (visual information), echoic (acoustic information), other sensory stores
• Capacity and duration of sensory register


  Capacity = very high

  Duration = less than 1/2 a second
• Coding, capacity and duration of STM


  Coding = Acoustic

  Capacity = 7+/-2

  Duration = 18 - 30 seconds
• Coding, capacity and duration of LTM


  Coding = semantic

  Capacity = unlimited

  Duration = lifetime
• How is information passed further into the memory store?

  Via Attention
• How can we keep information in the STM?


  Via maintenance rehearsal
• How is information passed to the LTM?

  Prolonged rehearsal
• How do we recall information from LTM to STM?

  Via retrieval
• Characteristics of stores in MSM

  Unitary, passive, structural components and hypothetical constructs
• Tulving - types of LTM


  Episodic, semantic and procedural memory
• LTM - Episodic memory


  Ability to recall events from our lives.

  Time-stamped - know when it happened

  Will include things like ppl, places and objects.

  Make a conscious effort to recall memory
• LTM - Semantic memory


  Shared knowledge of the world

  Not time stamped

  Less personal and more about facts

  Less likely to forget or distort semantic memory
• LTM - Procedural memory


  Memory for sections and skills

  Recall without conscious awareness or effort
• Baddeley and Hitch


  Working memory model - how the STM is organised and how it functions
• Central executive (CE)


  Monitors incoming data, divides our attention and allocates subsystems to tasks

  Very limited processing capacity - does not store information
• Phonological loop (PL)


  Deals with auditory information (acoustic)

  Keeps the order in which the information arrives

  subdivided into 2 parts:

  - phonological store - stores the words you hear

  - articulatory process - allows maintenance rehearsal

  Capacity = 2 seconds worth of what you can say
• Visuo-spatial sketchpad (VSS)


  Stores visual/spatial information. (e.g. count how many windows in your house - you would visualise it)

  Capacity = limited up to 3-4 objects

  subdivided into 2 parts:

  - visual cache - sores visual data

  - inner scribe - records arrangements of objects in the visual field
• Episodic buffer (EB)


  Temporary stores for information from other subsystems.

  storage component for CE

  Capacity = limited - 4 chunks

  Links working memory to LTM and wider cognitive processes such as perception
• Interference theory


  Two pieces of information disrupting each other, results in forgetting one or both pieces of information or distortion of memory
• Proactive interference


  Older memory interferes with new memory.
• Retroactive interference


  New memory interferes with old memory
• McGeoch and McDonald study procedure


  studied retroactive interference

  ppts had to learn 10 words until they could remember with 100% accuracy

  Then they learnt another list of words

  6 groups of ppts different conditions:

  - synonyms

  -antonyms

  - words unrelated to original

  - consonant syllables (ABC)

  - 3-digit numbers

  - no new words - control group
• McGeoch and McDonald study findings

  When ppts were asked to recall original list of words, synonyms produced worst recall.

  Shows interference is strong when memories are similar
• McGeoch and McDonald study - explanation for findings


  Similarity effects recall due to proactive interference or retroactive interference
• Retrieval failure


  Not being able to access memories which are available
• Encoding Specificity Principle


  If a cue is going to be helpful it has to be

  1) present at encoding (when we learn the material)

  2) present at retrevial

  
  

  If cues available at encoding and retrieval are different then there will be forgetting.
• Types of non meaningful cues

  Context-dependant forgetting - recall depends on external cues

  State-dependent forgetting - recall depends on internal cues
• Research on context dependent forgetting

  Godden and Baddeley

  Study was done on deepsea divers

  diers learnt a list of words on land or underwater and were asked to recall on land or underwater

  4 categories:

  learn on land - recall on land

  learn underwater - recall underwater

  learn on land - recall underwater

  learn underwater - recall on land
• Research on context dependent forgetting - findings


  In 2 of the conditions context of learning and recall matched and in 2 other conditions they did not.

  Accurate recall was 40% lower in non-matching conditions

  Concluded cues available at learning were different from cues at recall leading to retrieval failure
• Research on leading questions

  Loftus and Palmer

  45 ppts were made to watch clips of car accidents and then were asked questions about them

  In the critical question (a leading question) ppts were asked to describe how fast the cars were travelling: 'about how fast were the cars when they hit each other?'

  There 5 groups, and each group was given a different verb when asked the critical question e.g. hit, contacted, bumped, collided, smashed etc
• Research on leading questions - findings

  A mean estimated speed was calculated for each group

  the verb 'contacted' resulted in a mean speed of 31.8mph

  verb smashed = 40.5mph
• Reason for leading questions affecting eyewitness testimony (EWT)

  Response bias explanation: the wording of the question influences how ppts choose to answer.
• Substitution explanation - Loftus and Palmer 2nd experiment


  Wording of the leading question changes ppt's memory of the film clip.

  ppts who heard the verb 'smashed' were more likely to report having seen broken glass (there was none) than those who heard hit