Topic 2: Memory Flashcards
State the three main processes that memory involves. Briefly explain each process. (3)
ESR
Encoding- storing information in different ways
Storage- holding the information in memory
Retrieval- bringing the stored infromation into conscious awareness
State the three main structures in memory. Briefly explain each structure. (3)
Sensory memory- brief, limited store for sensory data and holds large amounts of information for a short time before filtering into working memory
Short term memory (STM)- temporary storage system that processes incoming sensory memory
Long term memory (LTM)- unlimited storage system that takes information from STM and stores them over an extended period of time
How can the three main structures of memory differ? (3)
CDE
Capacity- how much information they can hold
Duration- How long they can hold the information for
Encoding- The form in which information is stored
Describe the capacity, duration and encoding of sensory memory, STM and LTM. (9)
Sensory memory
Capacity- unlimited
Duration- 250 milliseconds
Encoding- varies between sensory organs e.g. visual excites retinal cells, sound create vibrations in the ear
STM
Capacity- limited, 7+ or - 2 items (Miller)
Duration- 18-30s without rehearsal (Peterson & Peterson)
Encoding- mainly acoustic (Baddeley)
LTM
Capacity- unlimited
Duration- potentially forever
Encoding- mainly semantic (Baddeley)
Describe and evaluate case studies for STM capacity. (8)
-Serial digit span experiment presented participants with increasing lists of numbers/letters until they were getting them wrong 50% of the time.
-Results: STM capacity was 9 numbers and 7 letters
-Miller supported this, suggesting we can remember 7+ or - 2 items. Found people can recall 5 words as well as 5 letters
Evaluation:
Against
-Not replicated: Miller’s findings haven’t been replicated. —> His findings is questionable. False positive results?
-STM may be limited to 4 items. —> STM may not be as extensive as first thought.
-Chunk size matters: Shorter memory span for larger chunks such as 3-syllable words. —> STM has limited capacity.
For
-Individual differences: Found that STM capacity increased with age, from 7 digits at age 8 to 9 digits at age 19, possibly due to changes in brain capacity and/or development of strategies such as chunking —> capacity of STM is not fixed and individual differences may play a role.
Describe and evaluate case studies for LTM capacity. (8)
-Study estimated the number of possible neural connections as 1 followed by 10.5 million kilometers of zeros —> LTM is extremely large
-Study on Shereshevsky, who had an outstanding memory, could remember almost every detail of his life.
-He was given long lists of numbers, letter etc…, which he remembered even decades later. —> LTM capacity could be potentially infinite.
Evaluation:
Against
-Results are generalised: Shereshevsky was studied because he had an outstanding memory —> Results are not representative of the general population as individual was very unique.
-Population validity: Study was done on one or a few people —> challenges population validity
For
-Study displayed rich, detailed data (possible neural connections as 1 followed by 10.5 million kilometers of zeros) —> Evidence is irrefutable
Describe and evaluate case studies for STM duration. (8)
-Trigram retention experiment studied 24 students who were given 3 consonants with no meaning e.g. BRZ.
-During retention intervals of 3-18 seconds, participants counted backwards from large numbers.
-Results: 90% recall after 3 seconds, only 6% after 18 seconds, indicating STM duration is between 18-30seconds
Evaluation
Against
-Displacement vs. decay: Participants were counting numbers in their STM which may displace the syllables. Trigram experiment was repeated but using tones instead of numbers and found STM lasted longer —> Forgetting was due to displacement rather than decay.
For
-Artificial task/mundane realism: While memorising consonant syllables may not reflect everyday memory activity, it reflects some real-life tasks like remembering phone numbers or postcodes. —> Although the task was not highly realistic, the study does have some relevance to everyday life.
Describe and evaluate case studies for LTM duration. (8)
-Studied 400 participants (ages 17-74) asked to recall high school classmates’ names and recognise classmates in photos.
-Those who left school in the last 15 years recalled 90% of names and faces.
-Those who left 48 years ago recalled 80% of names and 70% of faces.
-Suggests LTM for faces lasts a long time, and LTM duration could be potentially forever.
Evaluation
Against
-Limited to one school —> results may vary by school size/type.
For
-High population validity (400 participants, wide age range) —> results can be generalised to wider population
-Task was realistic —> More applicable to how real life LTM works. Increases external validity.
Describe and evaluate case studies for coding in memory. (8)
-Baddeley tested whether STM was encoded mainly acoustically (sound based) or semantically (meaning).
-75 participants given 4 types of word lists: acoustically/semantically similar/dissimilar words.
-Each list repeated 4 times. Then given list of stimulus words to be rearranged in correct order.
-Results: acoustically similar words 10% correct, other three 60-80% correct
-Suggests that STM is mainly encoded acoustically whilst LTM is mainly encoded semantically.
Evaluation:
Against
-STM may not be exclusively acoustic: A study found STM was encoded visually when verbal rehearsal was prevented in a visual task —> STM can have multiple forms of coding
-LTM may not be exclusively semantic: There are different types of LTM (procedural, episodic, semantic) which may encode info differently. Research found that LTM can be encoded visually or acoustically, not just semantically. —> LTM can have multiple forms of coding
-Baddeley may not have tested LTM: In Baddeley’s study, there was only a 20 minute delay to test LTM. —> challenges validity of results as LTM may not have been tested.
For
-High population validity: 75 participants —> population validity means results can be generalised to the wider population
-Mundane realism: realistic task (we communicate and listen everyday) —> Results can be applied to real-life. Increases external validity.
-Face validity (seems sensible on the surface): Results seem plausible as we remember the meaning of an event from some time ago (LTM semantic) but not what was exactly said (STM acoustic). —> supports idea that LTM is encoded semantically, whilst STM is encoded acoustically
Outline the Multi-store model of memory (6)
-The multi-store model of memory (MSM) consists of three separate memory stores connected by processes that transfer information between stores.
-This includes the sensory register, attention, STM, rehearsal, LTM and retrieval.
-The sensory register is the place where sensory information is briefly (250 milliseconds) held at each of the corresponding brain areas.
-If a person’s attention is focused on one of the sensory registers, the data is transferred to short-term memory (STM) which has limited duration (18-30s) and capacity (7+ or - 2 items), and is used for immediate tasks.
-Repetition keeps information in STM, but eventually such repetition will create a long-term memory (LTM). This is called maintenance rehearsal.
-LTM is potentially unlimited in duration and capacity.
-Retrieval is the process of getting information from LTM and passing it back through STM for use.
-STM is mainly encoded acoustically, whereas LTM is mainly semantically.
Discuss the multi-store model of memory. (16)
-The Multi-Store Model of Memory (MSM) consists of three separate memory stores connected by processes that transfer information between stores.
-This includes sensory register, attention, short-term memory (STM), rehearsal, long-term memory (LTM), and retrieval.
-The sensory register is the place where sensory information is briefly (250 milliseconds) held at each of the corresponding brain areas.
-If a person’s attention is focused on one of the sensory registers, the data is transferred to short-term memory (STM) which has limited duration (18-30s) and capacity (7+ or - 2 items), and is used for immediate tasks.
-Repetition keeps information in STM, but eventually such repetition will create a long-term memory (LTM). This is called maintenance rehearsal.
-LTM is potentially unlimited in duration and capacity.
-Retrieval is the process of getting information from LTM and passing it back through STM for use.
-STM is mainly encoded acoustically, whereas LTM is mainly semantically.
Evaluation:
For
-Free recall study presented participants with long lists of words which could be recalled in any order. Serial position effect: better recall for words at the beginning (primacy effect, more rehearsal, transferred to LTM) and end (recency effect, still in STM) of a list, with poorer recall for middle words (displacement) —> Info poses from sensory register to STM before LTM. Separate memory store.
-Amnesia cases: Damage to brain can affect one type of memory but leave others alone. Reported case of Korsakoff’s syndrome who damaged STM (auditory span was only 1 or 2) but not LTM. —> Separate memory store
-Brain scans: Found active prefrontal cortex during STM tasks and active hippocampus in LTM tasks. —> Reliable as scans are unbias and objective. Measure everyone equal and produce output that can be fairly compared. Valid results.
-Overall agrees with idea of separate memory stores.
Against
-Criticism of KF case: In K.F.’s case, STM damage affected only acoustic coding, not visual —> There are multiple types of STM, unlike the MSM, which proposes a single, unitary STM store.
-Clive Wearing: procedural and semantic memory still intact, could still remember to sing/play piano and his wife’s name even though he forgot everything that happened in the past —> There are multiple types of LTM, unlike the MSM, which proposes a single, unitary LTM store.
-Rehearsal not = STM-LTM transfer: Research found repeated information (BBC wavelengths) wasn’t retained —> Rehearsal does not necessarily transfer STM to LTM. There are other components that cause this transfer.
-Depth of processing is key: A study found that participants remembered better from deep processing than shallow processing. —> Depth of processing is key to the STM-LTM transfer
Outline the working memory model. (6)
-Represents what we are consciously thinking about at any moment.
-This includes the central executive and slave systems.
-Central executive involves decision making and can coordinate out performance. No storage capacity but can process info in any modality e.g. visual, auditory etc…
-Articulatory or phonological loop (slave system) involves auditory info split into two parts: Articulatory control system (inner voice) and phonological store (inner ear).
-Visuospatial sketchpad (slave system) handles visual and spatial info, including movement perception and physical action control. Split into two parts: the visual cache, which stores visual item info, and the inner scribe, which stores object arrangement in the visual field.
-Episodic buffer is a limited-capacity store that holds both visual and acoustic info, integrating data from the central executive and other slave systems while maintaining time sequencing.
Discuss the working memory model. (16)
Representing what we are consciously thinking about at any moment. This includes the central executive and slave systems.
Evaluation:
For
-Dual task method (a main reason of WMM development): Supports existence of central executive. Found task 1 (involved only central executive) was slower than task 2 (involved either only articulatory loop or both articulatory loop and central executive) —> Supports idea that central executive is a component of working memory.
-A study found that participants struggled with two visual tasks (tracking light whilst describing angles) but found visual + verbal tasks easier. —> Easier to do tasks involving different slave systems. Supports idea of separate visual and spatial systems.
-KF damaged his STM in a motorbike accident. Could remember visual but not auditory info. —> STM is not a unitary system
Against
-Problem with case studies:
-Might have had other unknown brain damage before the accident —> Wired differently beforehand. Results may be due to unknown brain damage rather than from accident.
-Individual differences: Memory varies among individuals —> Using brain-damaged people to generalise how memory works may challenge the validity of the results. May not measure what research claims and intends to.
-Problem with central executive: It has a wide range of functions making it difficult to define its precise role. Immeasurable capacity. Potentially more than one component in the central executive. —> Limited knowledge about central executive. Difficult to fully rely on model.
-Study on a person called EVR, who had a cerebral tumour removed. Performed well on reasoning tests (central executive intact) but struggled with decision-making (central executive not fully intact)—> There are multiple components of the central executive.
-Does not involve LTM: Only a partial model of memory since it does not deal with LTM.
