Psychology -memory

• define memory


  The faculty by which the mid stores and remembers information; information is encoded, stored and retrieved
• what are the 3 key features for each memory store?

  - coding - the means by which information is represented in the memory

  - capacity - the amount of information that particular part of memory can store at any given time

  - duration - the length of time information can be stored in that particular part of memory
• the sensory register coding

  5 mini stores: iconic, echoic, haptic, gustatory, olfactory

  crowder - visual information in the SR seems to stay for a few seconds whereas auditory information seems to stay for 2 -3 seconds, suggesting different sensory information must be coded into different sensory stores.
• The sensory register capacity and duration

  - research suggests that the SR can hold large amounts of information as it takes information from all different sense receptors

  - Sperling - flashed a 3x4 grid of letter on a screen for less than a second. Different tones were used to indicate which row to recall. Recall of letters of indicated row was high suggesting that all info was originally there. Capacity =large

  - however, this information lasts for only a short amount of time, different sub-stores have different durations (crowder) but information decays very quickly in all stores
• Attention


  focusing on/ noticing a stimulus
• maintenance rehearsal


  repeating information without thinking about its meaning
• decay


  losing information because you have not used it enough
• displacement


  losing information because there is already too much in that memory store
• evaluating the sensory register

  - calculating capacity and duration of sensory memory stores involves experiments where the stimulus is artificial. (sperling) - task lacks mundane realism

  - research evidence (treisman) - presented identical auditory messages to both ears of participants but with a slight delay between them. Participants noticed the messages were identical if the delay was 2 seconds or less suggesting that the echoic store might have a duration of about 2 seconds
• Short term memory coding

  - primarily coded acoustically but other codes exist too

  - baddeley gave different lists of words to 4 groups and they were asked to recall them in the correct order. When asked to recall words immediately, they did worse with acoustically similar words but when asked after 20 minutes, they did worse with semantically similar words.STM= coded acoustically
• short term memory capacity

  7 +/- 2

  - this can be stretched if information is chunked together

  - Jacobs - the researcher reads out 4 digits and the participant recalls these out loud in the correct order. If correct, the researcher reads 5 digits and so on until they fail on 50% of the task = digit span. He found that the mean across all participants was 7.3 letters

  - However, Danemane and carpenter found that reading comprehension affected STM capacity. Individual variation were between 5 and 20 items. There are individual differences in STM capacity
• short term memory duration

  30 seconds

  - prolonged rehearsal moves info to the LTM

  - Peterson and Peterson - read participants a series of trigrams and asked them to count backwards in 3s from a number. They found that around 90% of trigrams were recalled correctly after 3 seconds, but after 19 seconds this dropped to only 5%. This made them estimate the duration to be between 20 and 30 seconds
• Long term memory coding

  mainly semantic however other forms of coding exist

  - memories may change or merge with other memories meaning they are not always accurate

  - Baddeley - when asked to recall semantically similar words after 20 minutes, participants found this very hard.
• long term memory capacity

  unlimited

  - wagenaar created a diary of 2,400 events over 6 years and tested himself on recall of events rather than dates and found he had excellent recall suggesting the capacity is very large
• long term memory duration

  unlimited

  likelihood of lasting a lifetime is increased if a memory is coded semantically or if it is rehearsed regularly

  - bahrick et al, showed 400 participants aged between 17 and 74 a set of photos and a list of names and asked them to identify ex-school friends. Those who'd left high school is the last 15 years identified 90% of faces and names while those who'd left 48 years prior identified 80% of names and 70% of faces suggesting memories of faces is long lasting
• evaluating research on the LTM

  - weakness - there is evidence of different types of LTM (semantic, episodic, procedural), which might suggest that there are different types of coding or even different stores of each type of LTM which the model does not show

  - weakness - many studies into LTM duration test recognition rather than recall. Research suggests recognition is generally easier, so the type of testing technique used may explain findings into duration
• research to support the multistore model

  A - whether memory of words was affected by the number of words a person had to remember

  M - 103 psychology students listened to 20 word lists and were asked to recall what they heard

  R - likelihood of recall depended on the position of the word in the list. HIgh recall - first words (primacy effect). High recall - last words (recency effect) - serial position effect

  C- supports multistore model as it fits rge predictions. First words were rehearsed and transferred to LTM while lasts words were in the STM

  E - lacks mundane realism , sample may have demand characteristics
• evaluating the multistore model

  - weakness, criticised for over simplifying the STM, the wmm suggests that there are different components in the STM, including for visual and for auditory information, but the MSM does not show this

  - weakness, research suggests that repeating information is not always enough to move info to the LTM. New research focuses on elaborative rehearsal (linking information to existing knowledge or thinking about what it means rather than just rehearsal). Not accurate in the process of moving info from STM to LTM
• Vicari et al - case study of CL


  8 yo girl suffered brain damage due to the removal of a tumour. Had deficiencies in her episodic LTM functions, especially in creating new episodic memories but could still create and recall semantic memories. Suggests that episodic and semantic memories are separate systems

  - lack of research into procedural memory as there are very few cases where people lose only procedural memories making it difficult to know how it is associated with parts of the brain and whether or not it is biologically different to the other types of memories
• which memory stores are explicit, declarative

  episodic and semantic
• which memory store is implicit, non-declarative

  procedural
• episodic memories


  unique memories that are concerned with our personal experience of events including when they happened and all sensory information related to that memory
• semantic memories


  memories concerned with general knowledge
• procedural memories


  memories for carrying out complex skills, with enough practice we can use these memories automatically
• Tulving et al


  A- investigating differences in processing of episodic and semantic memory tasks

  M- 6 volunteers including him and his wife were injected with radioactive gold and scanned with a gamma ray detector. 8 trials that lasted 30 seconds. Participants lied on a couch and asked to recall the LTM.

  R- 3 has inconclusive data, others showed blood flow patterns in the posterior cortex for semantic memories and frontal lobe for episodic memories.
• dual task performance - gathercole and baddeley


  - participants had more difficulty doing 2 visual tasks (tracking a lights and describing the letter F) than doing both a visual and verbal task at the same time. This increases difficulty because both visual tasks compete for the same slave system whereas, when doing a verbal and visual task simultaneously there is no competition

  - supports the idea that there are separate verbal and visual parts of the working memory
• clinical case study of KF - shallice and warrington

  - the brain damage meant that KF has poor stm ability fr verbal information but could process visual information normally.

  - the phonological loop is damaged . The visuospatial sketchpad is in tact

  - supports the existence of separate visual and acoustic stores suggested by the WMM
• what does the working memory model consist of

  central executive

  visuospatial sketchpad

  episodic buffer

  phonological loof
• what does the multistore model of memory consist of

  sensory register - attention

  stm - maintenance rehearsal, prolonged rehearsal, decay, displacement

  ltm - decay, retrieval
• central executive


  - decides what is and isn't attended to

  - organised and manages information and delegates tasks to the slave systems

  - helps us to switch out attention between different inpits of information
• episodic buffer


  - responsible for integrating ongoing experiences into one flow of information that can be transferred into LTM

  - maintains a sense of time sequencing
• visuospatial sketchpad


  - deals with spatial and visual information

  - later divided into visual cache (stores visual data such as shapes and colour) and the inner scribe (records the arrangements of objects in our visual field)
• phonological loop


  -temporary storage system for auditory information and helps order information

  - later subdivided into the phonological store (stores what you hear) and the articulatory process (rehearses words to keep them in working memory whilst needed)
• coding, capacity and research of central executive

  - modality free

  - limited capacity

  - D'esposito - used fMRI scans and found that the prefrontal cortex was active when verbal and spatial tasks were performed simultaneously but not when performed separately suggesting the brain area may be associated with the CE functions attempting to divide the tasks.

  - vague concept, not clear how it works or what it does
• coding, capacity and research of phonological loop

  - acoustically (phonological store- recently heard words + articulatory process- repetition of information)

  - capacity - what can be said in 2 seconds

  - Baddeley - where participants recalled more short words in serial order than longer words, it supports that the capacity is set by how long it takes to say words rather than the number of words
• coding, capacity and research of visuospatial sketchpad

  - codes through mental pictures/ visual and spatial items

  - capacity of 3-4 objects

  - gathercole and baddeley - participants had difficulty simultaneously tracking a light and describing the letter F because they both use the same slave system, less difficulty with tasks using different slave systems

  - PET scans show activation in the left hemisphere with visual tasks and activation in the right hemisphere for spatial information supporting the idea of separate visual cache and inner scribe
• coding, capacity and research on episodic buffer

  - modality free

  - limited capacity of about 4 chunks

  - prabhakaran et al - use fMRI scans to find greater right frontal brain activation for combined verbal and spatial information but greater posterior action for non combined info . Biological evidence that EB holds integrated info
• theories of forgetting


  - interference

  - retrieval failure
• interference and types


  - when are memory is forgotten because it has been blocked by another, causing the memories to change or be forgotten

  - proactive - older memory disrupting newer ones

  - retroactive - new memory disrupts older one

  -worse when memories are similar

  - less likely to occur when there is a gap in the instances of learning
• McGeoch and McDonald


  Studied retroactive interference by changing the amount of similarity.

  Learn a list of 10 words, then learnt a new list of synonym, antonyms etc (6 conditions)

  As the test got more difficult and similar the more interference occurred affecting how many words they could recall

  - mundane realism, individual differences, standardised procedures