Memory Flashcards
Multi-store model
Richard Atkinson and Richard Shriffin (1968, 1971)
Describes how information flows through the memory system. The model suggests that memory is made up of three stores linked by processing
How many stores does the sensory register have
One for each sense
Two main stores in sensory register
Iconic memory
Echoic memory
Iconic memory
Visual info is coded visually
Echoic memory
Sound or auditory info is coded acoustically
Coding of sensory register
Modal
Capacity of sensory register
Very large
Duration of sensory register
< 0.5s
Maintenance rehearsal
Repeating material to ourselves over and over again
Keeps things in our STM’s
Coding of STM
Acoustically
Capacity of STM
Limited, 5-9 things
Duration of STM
30s unless rehearsed
Retrieval
Moving info from LTM to STM so we can recall it
Coding of LTM
Semantically
Capacity of LTM
Unlimited
Duration of LTM
Forever
How do we move things from the sensory register to STM
Paying attention
How do we move things from the STM to the LTM
Prolonged rehearsal
Strengths of multi-store model
The case of HM –> Removed hippocampus (epileptic), unable to encode new LT memories but STM was unaffected
The case of Clive Wearing –> brain damage, has working STM but not LTM
Supported by research showing LTM and STM are different
Weaknesses of multi-store model
Too simple, not enough evidence to suggest that STM is not a unitary store –> Shallice and Warrington (1970)
LTM involves more than maintenance rehearsal –> Craik and Watkins (1973)
Shallice and Warrington (1970)
Studied KF
STM for digits was poor when read out loud but recall was much better when he read to himself
Craik and Watkins (1973)
Found that elaborative rehearsal is also needed which is where you link the info to your existing knowledge, or you think about what it means
Digit span technique
Assesses capacity of STM (Joseph Jacobs (1887))
Average span for digits was 9.3 items and 7.3 for letters
Why is it easier to recall digits
10 digits vs 26 letters
George Miller (1956)
People can recall 5 words as well as they can recall 5 letters - ‘chunking’ enables us to remember more
Baddeley (1966a, 1966b)
Tested LTM by asking to recall word list they learnt 20 mins ago - not actually LTM
Jacobs (1887)
Capacity isn’t the same for all
Findings show digit recall increased steadily with age. Average for 8yo - 6.6 digits and 8.6 for 19yo
Vogel et al (2001)
Found 4 items were upper band of capacity of STM.
Millers range is inappropriate - too high
What does working memory model explain
How STM is organised and how it functions
What is the WMM concerned with
Part of the mind that is active when we are temporarily storing and manipulating information
Dual task performance
Doing two tasks at the same time
If they are both visual tasks, you perform them less well than if you do them separately. If one is auditory and the other visual, no interference
Baddeley and Hitch (1972)
What are the different stores in the WMM
Visual processing
Processing sound
Central executive
Attentional process that monitors incoming data, makes decisions and allocated slave systems to tasks
Where does data arrive from when going to the central executive
The senses or LTM
Capacity of central executive
V. limited
Slave systems
Phonological loop
Visuo-spatial sketchpad
Episodic buffer
Phonological loop
Deals with auditory info (acoustic coding) and preserves the order in which the info arrives
Subdivisions of PL
Phonological store
Articulatory process
Phonological store
Stores words you hear
Articulatory process
Allows maintenance rehearsal (repeating sounds/ words in a ‘loop’ to keep them in working memory)
Capacity of ‘loop’ is 2 sounds of what you say
VSS
Stores visual and/or spatial info when required
Has a limited capacity; 3-4 items (Baddeley)
What did Logie (1995) subdivide the VSS into
Visual cache - stores visual data
Inner scribe - records arrangement of objects in the visual field
Episodic buffer
Added by Baddeley in 2000
Temporary store for info, integrating the visual, spatial and verbal info processed by other stores
Maintains a sense of time sequencing (recording events/ episodes that are happening)
Seen as storage component of Central Executive
Capacity of episodic buffer
4 chunks
What does the episodic buffer link working memory to
LTM and wider cognitive processes e.g. perception
Positives of WMM
Clinical evidence - Shallice and Warrington (1970) - after brain damage KF could process visual info normally but had poor STM ability for verbal info
Dual task performance - Baddeley (1975); ppts struggled doing 2 visual tasks (tracking a light and describing letter F) but not with a visual and verbal one - supports separates stores
Brain scanning - Braver at al (1997) gave ppts task involving CE and found activity in left prefrontal cortex increased with difficulty levels
Studies of word length effect support PL - Baddeley (1975); ppl find it harder to remember longer words - finite space for rehearsal in articulatory process
Negative of WMM
Lack of clarity of CE - “most important but least understood component” (Baddeley, 2003) - component is unsatisfactory and explains nothing
Types of LTM
Episodic
Procedural
Semantic
Episodic memory
Personal memories of events
Have 3 elements: specific details of the event, the context and the emotion
Have to make a conscious effort to remember
Procedural memory
Remembering an action or muscle-based memory e.g. riding a bike
Automatic memories
Acquired through repetition and practice
Semantic memory
Remembering factual/ meaningful info shared by everyone
Not personal but usually start as episodic memories
May be abstract like maths or concrete, ice is made from water
When does interference occur
When 2 pieces of info conflict with each other, resulting in forgetting one or both of in some distortion of memory
Types of interference
Proactive
Retroactive
Proactive interference
Old memory interferes with a newer one
Retroactive interference
Happens when a newer memory interferes with an older one
Strengths of interference
Evidence from lab studies - McGeoch and McDonalds
Real life application - Rugby players
May easily be overcome through the use of cue - ppts given word list to learn then lost grew in size and recall dropped from 70%
Weaknesses from interference
Research was artificial - most common stimuli are random word lists - have no meaning to us
Time between learning the stimuli that are given in labs are quite short - can’t be sure it made it into the LTM and if interference only affects LTM
Not all affected by proactive interference - Kane and Eagle showed that if working memory is greater, less susceptible to proactive interference
Strengths of diff. types of LTM
Real life case studies - Clive wearing’s semantic memories were unaffected despite damage to other types of LTM
Real life application - Belleville et al (2006) showed episodic memories could be improved in those with cognitive impairments - important to distinguish types of LTM so treatments can be developed
Scientific research to support - Tulvung et al found that episodic memories (right prefrontal cortex) and semantic memories (left prefrontal cortex) - physical reality of LTM
Weaknesses of diff types of LTM
Contradicting - Cohen and squire (1980) - disagree with Tulving divides
Weapon Focus Effect
When witnesses see the weapon it makes them anxious and they focus all their attention on the weapon being used, resulting them in them having difficulties remembering other details of the event
IV in Johnsons and Scott (1976)
Low anxiety - pen covered in grease
High anxiety - knife covered in blood
DV in Johnson and Scott (1976)
How many ppt’s correctly identified the man
Johnson and Scott’s findings
49% with the pen
33% with knife
Fully supports the weapon focus effect, considerable difference in the two conditions
Yule and Cutshall (1986)
Gun shop owner shot a thief dead
21 witnesses; 13 agreed to take part
Interviewed 4-5 months later
Accounts compared to police interviews at the time of shooting
Witnesses rated stress out of 7 at the time
Findings of Yulle and Cutshall (1986)
Witnesses gave accurate accounts several months later
Ppt’s who were more stressed were most accurate (88% vs 75%)
Shows that heightened arousal associated with anxiety enhances the accuracy of EWT
Yerkes-Dodson Law
As arousal (anxiety) increases performance (accuracy) increases until an optimal point and then decreases
