Memory

• What is memory?

  Memory is the term given to the structures and processes involved in the storage and retrieval of information
• what is coding?

  The format of how information is stored

  Can be either acoustically or semantically
• What is capacity?

  How much information a memory store can store
• What is duration?

  How long a memory store can store information for
• STM-Coding-Baddeley (1966)

  • PPs given 4 different word lists which were acoustically similar/dissimilar or semantically similar/dissimilar
  • PPs were worse at recalling acoustically similar word list suggesting that similar sounds in words led to confusion in STM
  • Concludes that STM is mainly encoded acoustically
• Evaluation of Baddeley 1966 for STM-coding?

  • reliable due to standardised procedures therefore can be replicated
  • lacked ecological validity due to artificial stimuli
• STM-Duration-Peterson and Peterson 1959

  • 24 undergraduates given trigram and 3 digit number to count back from with ranging retention intervals
  • 80% recalled trigram correctly after 3 seconds but only 3% after 18 seconds
• Evaluation of Peterson and Peterson 1959 for STM-Duration

  • reliable due to standardised procedures therefore can be replicated
  • Lacks ecological validity due to artificial stimuli
• STM-Capacity-Miller (1956)

  • Used chunking and noticed that things tend to be remembered in groups of 7+/-2
  • Stated that grouping information together into meaningful pieces can increase the amount which can be remembered
• Evaluation of Miller 1956 for STM-Capacity

  • high in internal validity due to extraneous variables being controlled within the setting
  • not very reliable as STM capacity may have been overestimated since other researchers found that STM is only around 4+/-1
• LTM-Coding-Baddeley (1966)

  • PPs asked to recall word lists after 20 mins
  • Did worse when recalling semantically similar words
  • The similarity in meaning confused the PPs suggesting LTM is encoded semantically
• Evaluations of Baddeley 1966 LTM-Coding

  • reliable as standardised procedures were kept consistent for example all PPs were given the same amount of time
  • lacks validity as only one type of LTM was tested
• LTM-Duration-Bahrick et al (1975)

  • 392 PPs tested on recognising faces from high school photo yearbook and matching names with faces
  • Photo recognition-90% accurate recall 15 years since graduation and 70% after 45 years
  • Name recall-60% accurate recall 15 years after graduation and 30% after 45 years
• Evaluation of bahrick et al 1975 for LTM duration

  • high in external validity as memory was tested in a way which would be used in a normal environment
  • low in reliability because researcher didn't ask if any PPs were in contact with any classmates since graduation prior to the study
• What is the multi-store model of memory?

  A model of memory that describes how information is transferred from one store to another and how it is remembered or forgotten
• What is the sensory register?

  • Where we store sensory info from the environment before deciding what to do with it
  • Anything someone pays attention to in the sensory register goes to the short-term memory store, if something isn't paid attention to then it is forgotten
• How is information transferred from the short-term memory store to the long-term memory store?

  Information in the short-term memory store goes through the process of maintenance rehearsal until it is eventually stored in the long-term memory store through the process of prolonged rehearsal
• Primacy and Recency (cunitz)

  • Cunitz found that we tend to recall more words at the beginning of a word list (primacy) as it is transferred to the LTM through rehearsal
  • And more words at the end (recency) as this stays in the STM when needed to be recalled
• Baddeley encoding study for MSM

  • Gave PPs 4 trials at learning the order of a list of words and gave a 20 minute delay before recalling them
  • PPs had to recall as many words as possible in order
  • PPs STM was helping their LTM so an interference task after hearing the list of words was added to the 2nd test to remove the confounding variable
  • This cancelled out STM
  • In the 3rd test the words were displayed on a slideshow instead of tape recordings
• MSM evaluation?

  • Experiments testing aspects of the MSM are highly artificial, therefore memory isn't being measured in a naturalistic way making the MSM not very applicable to real world scenarios
  • Models of memory cannot be directly observed so researchers have to rely on inferences which can be unreliable since inferences are educated guesses and could be incorrect
  • There is empirical evidence supporting the idea of a distinction between STM store and LTM store in terms of coding, capacity and duration (baddeley 1966) this makes the MSM credible
• What is episodic memory?

  • Autobiographical record of personal experiences and events
  • The different parts of the memory are found in different parts of the brain but connected by the hippocampus
  • The memories are time stamped
• What is semantic memory?

  • Contains all knowledge that an individual has learned
  • the memories aren't time stamped
  • linked to episodic memories as new knowledge is gained from experiences
  • memories need to be consciously recalled to enable us to produce and understand language
• What is procedural memory?

  • ability to be able to be able to automatically perform learned tasks with little conscious thought
  • easy to perform but difficult to explain
• strengths of long-term memory?

  • credible due to neuroimaging evidence- Tulving et al (1994) where PPs asked to do different memory tasks while using a PET scanner which found that episodic and semantic memories were found in the prefrontal cortex
  • applicable- Belleville et al (2006) proved that episodic memories can be improved through training elderly people with cognitive impairments to focus on their episodic memories
• Weaknesses of Long-term memory?

  • Objection- In 2002 Tulving added to his theory stating that episodic memory is a specialised sub category of semantic memory which creates doubts on the idea that there are 3 types of long-term memory
  • Research lacks controls- Research into LTM tends to be based off case studies which lack generalisability since people involved weren't tested prior to their accidents/illnesses therefore we don't know how their memories were affected
• What does the working model of memory consist of?

  • Central executive
  • visuospatial sketch pad
  • episodic buffer
  • phonological loop
• Central executive

  makes decisions about which issues deserve attention and which should be ignored

  limited capacity as data arrives from senses but cannot be held for long
• Visuospatial sketch pad

  Stores visual and or/spatial (relationships between things) stored here

  limited capacity-3 to 4 objects
• Episodic buffer

  Baddeley added this store in 2000 as he realised the model needed a more general store

  integrates information from all other systems

  limited capacity of 4 chunks
• Phonological loop

  deals with auditory information and preserves word order

  Phonological store- holds words stored

  articulatory processes holds words heard/seen and silently repeated

  limited capacity of 2 seconds worth of words
• evidence for phonological loop (word-length effect research)

  • people cope better with short words than long words in working memory
  • phonological loop holds amount of information that can be said in 1.5-2 seconds
  • this makes it harder to remember a list of long words compared to shorter words
• Evidence for visuo-spatial sketchpad (Baddeley 1975)

  • PPs given visual tracing task while also being given task 1 or 2
  • 1.describe angles on letter F
  • 2.Perform verbal task
  • PPs found that doing task 1 was very difficult but not task 2, presumably because it used 2 slave systems
• Evidence for episodic buffer (Baddeley et al 1987)

  • PPs shown words and then asked to immediately recall
  • recall was better for sentences (related words) than unrelated words
  • supports the idea of general memory store that draws on semantics
• Limitations of WMM

  • Oversimplification of episodic buffer
  • No account for Long-term memory