Unit 3, topic 3 - memory Flashcards
describe long term memory (multi-store model)
Long term memory
Function - information in the LTM is encoded by meaning, semantically, stored in semantic networks.
Holds: holds vast amounts of information for a long period of time.
Duration: Relatively permanent.
Capacity: virtually unlimited.
Research: case studies (see LO-3.18) have helped scientists understand long term memory. We now know there are severa different types of long term memory.
describe short term memory (multi-store)
Short term memory
Function – information we are consciously aware of and can process (e.g. mental maths). What you are thinking about right now… is in your STM.
Holds – stimuli from the SM that have been attended to; information retrieved from LTM.
Capacity – 7+/-2 items (5-9 pieces of information; Miller, 1956).
Duration: 12-30 seconds (Peterson & Peterson. 1959).
Info is lost by – information is lost in two ways: trace decays (fading) and displacement (being pushed).
briefly summarise Sperling (1960).
Sperling (1960):
Aim – to investigate how much info (capacity) people can take in from briefly presented visual stimuli.
Experiment 1: Participants were quickly shown an array of 12 letters for 50msec and asked participants to recall as many as possible. Results: 4.5 out of 12 – he concluded it this way was a perception problem due to short exposure. Limitation: participants claimed they saw all but forgot while writing them down. Therefore not a capcity issue but memory definition.
Experiment 2: partial report method: similar array but a tone indicated which row (top, middle, bottom) particpants need to recall. Results: 3.3 out of 4 (82%). Additional experiments delayed intervals. Results: 0.5 sec delay = 50%; 1.0 ec delay = 33%.
describe sensory memory and its two stores (multi-store)
Sensory memory
Iconic memory: receives visual information from the environment.
Holds: visual stimuli (pictures).
Duration: approx. 0.2-0.4 seconds
Capacity: potentially unlimited
Research: Sperling (1960).
Echoic memory:
Function – involved in speech and language comprehension.
Auditory stimuli (sounds).
3-4 seconds
Potentially unlimited.
draw the multistore model of memory and who is it by
what does it describe
Atkinson and Shiffrin (1968)
Multi-store model of memory:
The multi-store model of memory describes the three stores of memory (Atkinson & Shiffrin, 1968).
The multi-store model of memory describes three stores of memory: sensory memory (SM), STM and LTM.
describe the process of encoding
Encoding: the process of converting sensory info (sight, sound, taste, touch, smell) into a usable form or memory trace that can be stored. Encoding occurs in 2 steps:
Acquisition – some sensory information is stored, temporarily (about 1 second) in a buffer, during this time it is available for processing before disappearing.
Consolidation – the process during which changes in the brain stabilises a memory resulting in LTM.
describe the process of storage
Storage: the result of acquisition and consolidation – represents the “permanent” record if the information.
We out information to the ‘back of our minds’
We store info in an organised way to make it easier for us to recover memories when we need them.
describe the process of retrieval
Retrieval: involves accessing stored info and using it to create a conscious representation or to execute a learned behaviour, such as a motor act.
Paradox of memory – our memories are surprisingly good in some situations and surprisingly poor in others.
describe long term memory
Long term memory
Function - information in the LTM is encoded by meaning, semantically, stored in semantic networks.
Holds: holds vast amounts of information for a long period of time.
Duration: Relatively permanent.
Capacity: virtually unlimited.
Research: case studies (see LO-3.18) have helped scientists understand long term memory. We now know there are severa different types of long term memory.
discuss the working memory model of memory
Working memory – a limited-capacity system for temporary storage and manipulation of information for complex tasks such as comprehension, learning and reasoning.
A limitation with the multi-store model of memory is that it provides a simplistic view of memory that doesn’t account for dynamic processes involved in cognitions, such as understanding language and dual processing (the ability to attend to multiple stimuli at the same time).
Consequently, Baddeley and Hitch (1974) introduced the term ‘working memory’ (rather than STM) to capture the dynamic, present and conscious aspect of memory.
They later developed the working model of memory.
Baddeley concluded that working memory must be dynamic and consist of a number of components that can function separately.
what are the stages of the working model of memory
Working model of memory (Baddeley and Hitch, 1974).
The phonological loop
The visuospatial sketchpad
The central executive
Episodic buffer (added in 200 to address WMM limitations).
Crystalized systems represent cognitive systems capable of cumulating long-term knowledge.
Fluid system – represent ‘fluid’ capabilities (such as attention and temporary stage), themselves unchanged by learning.
explain the phonological loop
The phonological loop
The phonological store (inner ear) holds verbal and auditory information. EG; phone number. It has limited capacity and duration.
This helps us understand a sentence of more than a few words; it retains words from the beginning of the sentence until we have heard the words at the end.
The articulatory rehearsal process - delays decay and enables you to hold onto information in sound-based form (inner voice) using sub-vocal maintenance rehearsal.
If internal rehearsal is disrupted or eliminated, phonological storage cannot occur.
The word-length effect supports the phonological loops as it is easier to rehearse shorter words than longer words.
explain the visuospatial sketchpad
The visuospatial sketchpad
It’s a mental workspace for temporarily storing and manipulating visual (what you see) and spatial (location in space) information.
explain the central executive
Central executive
The cental executive is the working component of working memory as all functions of the central executive involve the manipulation of information temporarily held in the phonological loop and visuospatial sketchpad.
Three main functions of the central executive:
Inhibition: an aspect of attention which involves screening out irrelevant matieral (selective attention).
Switching: changing attention from one item to another.
Updating: modifying items brough in from the LTM before re-committing them to memory through the episodic buffer; creating a process of accommodation of the semantic network.
what are the limitations of the working model of memory
Limitations of the working memory model:
Working memory can hold more than would be expected based on just the phonological loop or visuospatial sketchpad. For example, people can remember long sentences 15-20 words long. This is related to chunking (grouping meaningful units together), and LTM, I.e., knowing the meaning of words and how to relate parts of the sentence together (grammar). As a result Baddeley added a 4th component to the model: the episodic buffer.
explain the episodic buffer
The episodic buffer
Is a sub-system of working memory that enables the different components of working memory that enables the different components of working memory to interact with LTM.
Called ‘episodic’ because the sub-system can ‘pull together’ separate streams of info and combine them into scenes or episodes like memories of a story or movie scene.
Called a ‘buffer; because it provides a temporary working space.
Controlled by the central executive.
explain the levels of processing model
who was it proposed by and when?
The levels of processing model of memory (Craik and Lockhart, 1972).
This model suggests that the wat information is encoded (visual, phonemic or semantic) affects memory recall.
The deeper level of processing, the better the chance of retrieval from memory at a later time.
According to Craik and Lockhart, there are three levels of processing:
explain visual encoding
Visual encoding (also called structural encoding):
Concerned with the appearance: structural or physical features.
Leads to fragile memory trace -> fairly short-term retention
Visual encoding is a shallow form of processing.
explain phonemic encoding
Phonemic encoding:
Concerned with sound/ auditory processing
Phonemic encoding is an immediate form of processing
Involves maintenance rehearsal (repetition without change)
Produces a higher form of recall than visual encoding.
explain semantic encoding
Semantic encoding
Concerned with meaning.
Involves elaborative rehearsal, meaningful linking. The meaning of the word is encoded by relating it with words or similar meanings.
Thus, creates a more meaningful analysis.
Leads to a more durable memory trace and higher recall rate.
discuss the study conducted by Craik and tulving
Craik and Tulving (1975) Study:
Aim – to investigate how deep and shallow processing affects memory recall.
Method:
Participants were presented with a series of 60 words about which they had to answer one of three questions. Some questions required participants to process the word in a deep way (e.g. semantic) and others in a shallow way (e.g. structural or phonemic).
e.g. structural = does this word have a capital letter or small letter?, phonemic = does the word rhyme with __?, semantic = does the word go in this sentence __?
Participants were then given a long list of 180 words into which the original words had been mixed. They were asked to pick out the original words.
Findings – only about 20% of words were recalled after structural encoding, approx. 50% of words were recalled after phonemic, 80% or more words were retrieved after semantic encoding.
evaluate the levels of processing
Levels of processing model evaluation:
Strengths:
Explains why some things are remembered better and longer than others.
Highlights the importance of elaboration on enhancing memory.
Practical applications – students when studying.
Criticisms:
It does not explain how the deeper the processing results in better memories.
Deeper processing takes more effort than shallow processing and it could be this, rather than the depth of processing that makes it more likely that people will remember something.
The concept of depth is vague and cannot be observed. Therefore, it cannot be objectively measured.
long term memory
Long term memory – refers to the relatively permanent system that holds a vast amount of information for a long time (possibly indefinitely).
LTM primarily interacts with STM or short-term working memory
Info is encoded by meaning and stored in semantic networks, a hierarchical pattern of nodes linked to related nodes.
LTM results from physiological changes to the neurons and synaptic connections.
Difficult to measure capacity and duration. It Is considered that forgetting LTM is due to poor retrieval cues.
how is info stored in long term memory
Collins and Quillian’s (1969) hierarchical model proposes that concepts (knowledge) are arranged in networks.
The network consists of hierarchical nodes (concepts), interconnected by links.
Each node represents a category or concept (coloured).
Each concept has a number of properties.
Related nodes are connected.
Hierarchical: levels are arranged so that more specialised things are at the bottom, and more general things are at the top.
Additional properties can be determined by moving up the network.
Storing shared properties at higher level nodes improves cognitive efficiency and storage economy.
Note – this model is testable: it takes longer to recall (activate) notes that are further connected than closer connected. - forms the basis of Al neural networks models.
what are the types of long term memory
Types of long term memory:
Explicit/declarative memory (“knowing what”):
Requires conscious effort.
Important areas of the brain include hippocampus, amygdala and neocortex.
Implicit/procedural memory (“knowing how”):
Does not require conscious effort
Located in the basal ganglia and motor cortices. Cerebellum plays an important role in learning motor skills.
provide evidence supporting implicit and explicit memory
Evidence supporting implicit and explicit memory:
Case studies – Henry M and Clive W.
Both has anterograde amnesia, inability to create new memories.
Both lost the ability to form explicit memories but retained the ability to retain implicit memory.
HM was able to learn mirror tracing, he got really good at it but had no recollection of learning it.
Both are powerful examples of why we distinguish between implicit and explicit memory.
Patients with damage to their hippocampus have enabled researchers to realise that there are two types of LTM: explicit and implicit memory. Researchers studies PET scans of participants while they undertook activities that required the use of explicit and implicit memories. They found that the hippocampus was active for explicit memory tasks, but other parts of the brain were active for procedural memory tasks. For example, the cerebellum was, in part, responsible for remembering motor-skills tasks (Sanes, Dimitrov & Hallet, 1990; Schachter et al. 1996).
explain explicit/declarative memory in greater detail
Explicit/declarative memory - memory of specific facts or events that can be brought into conscious awareness and explicitly stated or ‘declared’ (unless retrieval fails).
Can be divided into 2 branches – episodic and semantic memory.
Episodic – memory of specific events or personal experiences. Includes details of time, place, psychological and physiological state of the person when the event occurred. Episodic memory is like a mental diary, recording autobiographical episodes we experience. EG: what was your birthday like?
Semantic – memory of information we have about the world. It includes specialised knowledge in areas of expertise, academic knowledge, rules, everyday knowledge and the meaning of words. Semantic memories appear to involves facts that do not depend of a particular place or time. EG: rules of chess.
Evidence of episodic and semantic – case studies K.C.s
Both had damage to their hippocampi.
Both had LTM memory impairment.
Kent Cochrane (K.C) could not relive his past (episodic memory).
Italian K.C had difficulty with remembering general facts (semantic memory).
explain implicit/procedural memory in greater detail
Implicit/procedural memory –memory of actions and skills previously learnt, call does not require conscious effort.
Can be divided into 3 branches – priming, motor memory, classical conditioning.
Priming – refers to our ability to identify a stimulus more easily or more quickly when we have previously encountered similar stimuli.
Procedural motor memory – memory for motor skills and habits. EG: how to touch type, ride a bike, drive a car, log onto the internet.
Classical conditioning – a form of learning which produced an automated response to a conditioned stimulus.
what are the structures that are implicated in memory
Several structures of the brain play an important role in memory formation (encoding), storage and retrieval.
Hippocampi (spatial memory, memory consolidation).
Cerebral cortex (long term memory storage).
Amygdala (emotion).
Cerebellum (learning and motor memories).
Basal ganglia for motor memories (procedural memories).
explain the role of the hippocampus in memory
Hippocampi
Located inside the temporal lobe, one in each hemisphere, close to the Amygdala.
Involved in early memory stage, memory consolidation (the process of permanent storage or a memory).
Spatial navigation.
The cells of the hippocampus are able to reproduce cells which enables new memories to be formed.
Memory consolidation – the process that transforms new memories form a fragile state, in which they can be disrupted, to a more permanent, in which they are resistant to disruption.
Synaptic consolidation: fast – takes place over minutes or hours. Connections are strengthened by increasing the likelihood
Of signal propagation. Continued use (firing) of neural connections results in more receptors (called ‘gates’) being added. this is called long-term propagation (LTP). If the synapse is used less frequently, the receiving neuron removes gates from the membrane, weakening important connections.
Systems consolidation: slow – takes place over months or even years. Involves the gradual reorganisation of neural circuits within the brain (cerebral cortex). Incoming information activates a number of sensory and cognitive areas of the cortex. The cortical activity is coordinated by the hippocampus. Reactivation, a process wherein the hippocampus replays the information, helps form connections between cortical areas. Over time, connections are formed between the cortical areas, the role of the hippocampus reduces and eventually vanishes.
Evidence for system consolidation – Anterograde amnesia, inability to form new memories. Retrograde amnesia, is memory loss of events that happened before the injury.
explain how the hippocampus functions with memory
Functioning hippocampus
The functioning of the hippocampus can be disrupted by psychological factors such as stress, anxiety, depression and post-traumatic stress disorder (PTSD). Here is an interesting short (2 min) video about the relationship between PTSD and brain change.
It can also be damaged through brain trauma such as head injury.
Health-related conditions such as Alzheimer’s diseases, viruses such as herpes, encephalitis and various other conditions can also cause dementia.
Prolonged stress may cause the hippocampus to shrink and thereby disrupts its role in memory formation.
explain how the hippocampus and amygdala work together in memory
Amygdala and the hippocampus
The Amygdala modifies the strength and emotional content of memories; it also plays a key role in forming new memories specifically related to fear.
The permanence of emotional memories suggests that interactions between the amygdala, hippocampus and cortical areas are crucial in determining the stability of a memory – that is, how effectively it is retained over time.
In activating the hippocampus, the amygdala also plays a part in the consolidation of explicit memory with emotional content, such as winning an important sports competition.
explain how the cerebellum and hippocampus work together in memory
Cerebellum and the hippocampus
The cerebellum plays a role in the formation and retrieval of procedural memory.
It works with the basal ganglia and the motor cortex of the frontal lobe.
Without the cerebellum, learning procedural memories would take years instead of months. Therefore the cerebellum assists with the formation of procedural memory.
In retrieval, the cerebellum activates the relevant neural systems, thereby allowing you to automatically perform a task without conscious awareness.
define recall and the types of recall
Recall: retrieval of information using minimal cues.
Free recall – retrieve as much as you can in any order. EG: parts of brain.
Serial recall – recall information in the order in which it was presented. EG: digit span.
Cues recall – uses prompts (cues) to assist recall. EG: area of the brain that relays sensory information, starts with a T.
define recognition
Recognition: retrieval process that requires correct identification of information. EG: multiple choice. Generally more accurate then recall because it provides more cues. EG: use the given list to label parts of the brain.
define relearning
Relearning: learning again something that has already been committed to memory. This is the most sensitive measures of retention.
Saving score = original time – relearning time / original time multiple by 100%.
Relearning is the most sensitive measure of retrieval, recall is the less sensitive. This means relearning will detect the smallest amount of memory.
A more sensitive measure – will register that a memory is present even is only a small amount of the memory remains.
A less resistive measure – will only that a memory is present when a large proportion of the memory remains.
why do we forget
Forgetting – an inability to retrieve information.
We forget due to errors in:
Encoding – the memory trace was never formed.
Storage – the memory is no longer available.
Retrieval – the memory is still stored but cannot be retrieved due to lack of retrieval cues.
explain encoding failure theory
Encoding failure – we cannot remember what we have not encoded because the information has never entered LTM.
We selectively attend to only some of the sensory information received by our sensory receptors.
Trace decay refers to loss of information from STM.
Some info can get automatically encoded but usually it takes some effort.
According to the encoding specificity principle (Tulving and Thomson, 1973), associations formed at the time of encoding new memories will be the most effective retrieval cues.
Two main conditions that assist retrieval are:
External (context) dependent cues: information is easier to recall when it is encoded and retrieved in the same context. EG: if you had a coconut smelling candle burning when you were studying for an exam, and you smelt that scent during the exam – you are more likely to remember what you studied.
Internal (state) dependent cues are based on the physical or psychological state of the person when information is encoded and retrieved. EG: happy or sad mood or level of anxiety.
Evidence for encoding specificity principle:
Godden and Baddeley (1975) study: they asked drivers to memories a list of words (above ground), participants were then divided into a diving group (different context) and ground group (same context). The ground group were asked to recall info above the ground, and diving group were asked the same under water. They repeated this study asking all divers to memorise a list of words (under water).
Findings: recall was best in the same context (40% better).
define the three storage failure theories
trace decay theory states that forgetting occurs as a result of a trace, a form of physical or chemical change in the nervous system, fading from the STM before it could be converted to LTM.
lack of consolidation theory states that when we take in new info, a certain amount of time is necessary for changes to the nervous system (consolidation) to take place. disruption during this process can result in storage failure.
displacement theory states when STM if ‘full’ new info pushes out old info. the old info which is displaced, is lost.
explain retrieval failure theory
(tulving and thompson, 1973) suggests that the amount of info we are able to retrieve depends on the type of cue or prompt used.
retrieval cues - are mental prompts that we create either automatically or deliberately to assist recall.
eg: tip of the tongue phenomenon:
explain interference theory as a forgetting theory
interference theory states that forgetting occurs because memories interfere with and disrupt one another (Baddeley, 1999).
- proactive interference (pro=forward) - refers to the disruptive effect of prior learning on the recall of newly learned info. eg: when you reset your password but can only remember the old one.
- retroactive (retro=backward) - refers to the disruptive effect of newer info on the recall of old info. eg: when you live in another country and only speak french and you forget how to speak english as well.
evaluate the interference theory
strengths:
- face validity
- reliable - replicable
limitations;
- low ecological validity - laboratory experiments
- lacks mundane realism - researchers tend to use tests of recall which are partially prone to interference (eg: recall of word lists and nonsense syllables). additionally in real life interference may not occur as readily .
what is the effect of similarity in interference theory q
interference is likely to be most pronounced when the two sets of material are very similar.
identify the three memory improvement strategies
chunking
rehearsal (maintenance and elaborative)
mnemonics
discuss chunking
chunking refers to the process of groups items together for remembering
good way to increase the limited capacity of STM (7+/-2) because each chunk only occupies one location in memory.
chunks are most effective when they have meaning.
explain mnemonics
are devices to help us remember info.
they are a pattern of letters, ideas, associations which assist us in remembering something.
there are 4 forms of mnemonics: - visualisation verbalisation rhythm rhyme
method of loci
SQ4R
what is the method of loci
method of loci is a mnemonic that uses spatial memory to aid in recall. - sometimes called memory palace.
based on the idea that we are good at remembering places we know
- imagine a room, and attach the item you want to remember to that room.
what is the SQ4R method
survey, question, read, recite, relate and review is a form of mnemonic and is used to remember the six steps for active reading.
survey - scan text to get general idea.
question - consider the purpose of your assignment and pose questions to help guide deeper understanding.
read - read text.
recite - recite what you already know.
relate - relate what you have read to things you know.
review - look at key terms, review original Qs.
