MEMORY Flashcards
Define coding
Format in which info is stored
Define capacity
The amount of info that can be held in a memory store
Define duration
Length of time info can be held in memory
What is STM capacity, coding type and duration
CAPACITY: 5- 9 seconds
CODING: Acoustic (sound)
DURATION: 18-30 seconds
What is LTM coding, capacity and duration
CODING: Semantic (meaning)
CAPACITY: unlimited
DURATION: potentially forever
State the produced of research into coding (BADDELEY)
- participants had to recall lists of words in correct order.
- 4 groups:
- acoustically similar words
- acoustically dissimilar word
- semantically similar words
- semantically dissimilar words
STM RECALL: particpants had to recall immediately
LTM RECALL: recall after 20 mins
What were the findings of the research into coding (BADDELEY)
Findings:
STM recall: tended t do worse with acccousitcally similar words.
LTM recall: did worse with semantically similar words
- this suggests info coded semantically in LTM.
State the research into capacity - JACOBS
- Measured digit span
- researcher gave participants 4 digits then particpants asked to recall them aloud.
- if correct, researcher reads out 5 digits and so on until participant can no longer recall in correct order anymore.
- this determines the digit span.
State the findings into research into capacity (Jacob’s)
Found:
- mean span for digits: 9.3 items
- mean span for letters: 7.3 items
State what MILLER found about the capacity of STM
- Noticed things come in 7s e.g 7 days in week, 7 deadly sins ect
- suggest that the span for capacity of STM about 7 items (+ or minus 2)
- however miller also noted that people can recall 5 words as they can recall 5 letters
- done this by chucking
Peterson and Peterson research -PROCEDURE
- tested 24 undergrads
- each student took part in 8 trials
- 1 trial-= 1 test
- each student given CONSONANT SYLLABLE to remember
- also 3 digit number to count back from (prevent rehearsal)
- each trial told to stop after different amount of time (3,6,9,12,15,16) (RETENTION INTERVAL)
Peterson + Peterson- FINDINGS
- Recall worse as seconds increased
- suggests STM may be very short duration
- unless rehearsed
Bahrick research into duration of LTM- procedure
- 392 participants
- age 17-74
-high school year books gathers from participants - recall tested by:
1) photo recognition test
2) free recall
BAHRICK research into duration of LTM- findings
- participants tested within 15 yrs of graduation were about 90% accurate (photo)
- after 48yrs, recall declined to about 70% (photo)
- Free recall= less good than recognition
- after 15yrs = 60% accurate (free recall)
- after 48yrs = 30% accurate (free recall)
Shows LTM can last very long time
Research into CODING
EVALUATION
ARTIFICIAL STIMULI
LIIMITATION
- study used artifical stimuli rather than meanigful material
- word lists= no personal meaning to participants
- means have to be cautious about generalising findings of different kinds of memory tasks
- EXAMPLE: when processing more meaningful info, people may use semantic coding even in STM tasks
- suggests that the findings from this study have limited application
Research into CAPACITY
EVALUATION
LACKING VALIDITY
(Jacob= old)
- LIMITATION
- Jacob’s study conducted long time ago
- early research in psych lacked adequate control
- EXAMPLE:
- Some participants may have been distracted while they were being tested do they didn’t perform as well as they might have.
- this would mean that results might NOT be valid because there were CONFOUNDING VARIABLES that weren’t controlled.
HOWEVER- results of study have been confirmed in other research, supporting its validity.
Research into CAPACITY
EVALUATION
NOT SO MANY CHUNKS
LIMITATION
- millers research= may have overestimated capacity of STM
- EXAMPLE: Cowan 2001- reviewed other research and conducted that the capacity of STM was only about 4 chunks
- suggests that’s millers estimate of 5 is more appropriate than 7.
Research in DURATION
EVALUATION
MEANINGLESS STIMULI IN STM STUDY
LIMITATION
- Peterson + Petersons study used artifical stimuli material
- trying to memories constant syllables does NOT reflect most real life memory activities where what we are trying to remember is meaningful
- so some may say study lacked EXTERNAL VALIDITY
HOWEVER
- we sometimes do remember fairly meaningless things
E.g phone numbers
- so study not totally irrelevant
Research into DURATION
EVALUATION
HIGH INTERNAL VALIDITY (Bahrick)
STRENGTH
- it has higher validity
- real life meaningful memories were studies
- when studies on LTM have been conducted on meaningless pictures to be remembered, recall relates = LOWER (Shepard 1967)
- downside of such real life research= confounding variables not controlled
E.g participants may have looked at yearbooks and rehearsed their memory over years
What is the MSM
A representation of how memory works in terms of 3 stores
What are the 3 stores in MSM?
- Sensory register
- STM
- LTM
What is the sensory register?
The memory store for each of our 5 senses
- Coding in the iconic sensory register= visual
- Coding in echoing sensory register= acoustic
What is the capacity and duration of sensory register?
CAPACITY: HUGE (only what is paid attention to can be passed don to STM)
DURATION: very short (less than half a second)
Is the sensory register under cognitive control?
NO, info coming from the senses is detected and recorded automatically.
How can things from STM pass to LTM?
Rehearsal
What are the 2 types of rehearsal?
MAINTENANCE- repeating info
ELABORATIVE- linking to info already in LTM
How is info lost from LTM?
DISPLACEMENT (new info)
DECAY (lost over time)
MSM
EVALUATION
EVIDENCE THAT THE STM AND LTM STORES ARE SEPARATE PROCESSES
• Glanzer and Cunitz 1966
• Asked participants to free recall word list in any order
• Found recall was much stringer for words at the start and at end of list.
• Results suggest thee are separate short + long term memory stores, with the words first heard entering LTM and being recalled (primary effect) and the most recent words being held by STM and being recalled (recency effect)
• Struggled to recall middle words (displaced)
MSM
EVALUATION
There is more than one type of STM
• The MSM states that STM is a unitary store (only 1 type of STM)
• However, evidence from people suffering from AMNESIA shows that this CANNOT BE TRUE
• Example:
• Patient studied KF, patient with amnesia
• found that KF’s STM for digits was very poor when they read them out loud to him
• But recall was much better when he was able to read digits himself.
• Further studies of KF and other people with amnesia showed that there could be another STM store for non verbal sounds (such as noises)
• The unitary STM is a limitation of MSM because research shows that at the very least there must be 1 STM store to process visual info and another to process auditory info
MSM
EVALUATION
There is more than 1 type of rehearsal
• Acorfing to MSM, what matters is rehearsal is the amount of it that you do.
• So more rehearsal of info, the more likely you transfer it to LTM.
• HOWEVER: CRAIK+WATKINS 1973- found that his prediction = wrong
• What really matter sis rehearsal type.
• Discovered 2 types of rehearsal
• MAINTENANCE REHEARSAL = type described in MSM
• But this type does not transfer info to LTM
• Just maintains it in STM
• ELABORATIVE REHEARSAL- needed for long-term storage
• Occurs when toy link the info to your existing knowledge, or you think about what it means
• very serious limitation of MSM as it is another research finding that cannot be explained by model.
MSM
EVALUATION
Cognitive experiments testing aspects of the MSM are often highly artificial
- highly artificial
- lacks external validity
- low ecological validity, results collected in lab environment may not be generalisable to other naturalistic situations like school and work
- also lack of mundane realism, experimental tasks testing the MSM are unlike how people use their memory in real life scenarios
What are the 3 types of LTM?
Episodic- episodes in our lives
E.G a gig you went to last week
Semantic- knowledge of the world
E.G knowledge of things like animals
Procedural- actions/ skills/ how we do things
E.G driving a car
What is a declarative/ explicit memory?
Consciously recalled and can be put into words
What is a non declarative/ implicit memory?
Can’t be consciously recalled and is difficult to put into words
E.g how to actually walk/ride a bike
What types of long term memory are declarative and which are non declarative
DECLARATIVE= episodic and semantic
NON DECLARATIVE= procedural
List facts/ features of episodic memory
- declarative
- time stamped (stored with reference to time + place)
- recalled consciously
- autobiographical (you are part of the memory)
- easiest memories to forget
- level of emotion felt at time, influences strength of memory
- first coding in prefrontal cortex, stored across the brain connected by hippocampus
List facts/features about semantic memory
- declarative
- may not recall when learnt/encoded (not time stamped)
- recalled consciously
- not autobiographical (nit in semantic memory)
- resistant to forgetting
- how deeply processed influences strength
- parahippocampal cortex