Week 5 Slides Flashcards
Define Memory
- The Process - Encoding, Retaining, Retrieving and Using information after the original stimulus is no longer present
- Is Recalling - images, events and ideas
Active any time past experience impacts thinking and behaviour in the present
What is Long-term Memory
- Can be divided into STM & LTM
- memory constructs often overlap in functions
- We need to be careful how we divide memory
- Behavioural experiments and Neurophysiological studies can infer how we use memory
What is Long-term Memory
- Responsible for storing information for long periods of time
- Extends from just a few minutes in the past to earliest memories
Long-term Memory Interacts
- Retains information from past
- Interacts with STM and Working Memory to create current experience
Serial Position Curve
- Murdock 1962
- Asked subjects to listen to a list of words and then write them down as they remember
- Participants are more likely to remember the beginning of a list and the end of the list
- Primacy Effect
- Recency Effect
- Serial Position Curve
- Murdock 1962
- Primacy Effect
- Recency Effect
Primacy Effect
- People have more time to rehearse words at the beginning of a task
- These words are more likely to be transferred to LTM
Serial Position Curve - Rundus 1971
- 20 word list at 1 word/5 sec
- Found the SPC that Murdock found
- Also found the early words were repeated most often
Recency Effect
- Mudock 1962
- Most recently shown words are still in STM
- They are more easily recalled
Serial Position Curve - Glanzer & Cunitz 1966
- Asked participants to count backwards for 30s after hearing last word
- Mostly remembered words from beginning
- Recency Effect was eliminated as words no longer in STM
Semantic Coding in Memory
- How is meaning stored in STM/LTM
- Wickens et al
- SUbjects in two groups to recall three words across 4 trials
- One group fruits, other group three proffesions and one fruit
Wickens et al Findings
- Performance in the Fruit only group worsened
- This was due to proactive interference
- Performance in the Professions group worsened across three trials
- Professions group improved on final fruit trials
- Evidence that meanings of words are encoded in STM
Sachs 1967
- Many people identified the correct sentence as changed
- Still many people also identified the wrong sentence even though the wording was different
- Evidence that people don’t remember specific words
- Actually they remember the general meaning of the passage
Henry Molaison
- Underwent surgery to eliminate seizures
- Successful in eliminating seizures but also left him unable to form new memories
- STM remained intact but not able to transfer any STM to long term memory
- Evidence that STM & LTM served by separate brain regions
Double Dissociation
- Patient KF had parietal lobe damage from a motorcycle accident
- KF exhibited normal LTM but poor STM
- Reduced digit span to 2 and reduced Recency effect
- Evidence that LTM & STM are different parts of the brain and independent mechanisms
Ranganath & D’Esposito 2001
Presented a sequence of stimuli to participants under fMRI.
• Sample face for 1 s
• Delay for 7 s
• Show a face
• “Does this face match the sample?”
- Hippocampal activity increases if the “same face” is new
- Hippocampus is involved in maintaining new information during short delays
LTM Summary
LTM is responsible for storing information for long periods
Interacts with STM and Working Memory to create our ongoing experiences
Evidence that STM & LTM are used for tasks
- Serial Position Curve
- Primacy Effect
- Recency Effect
Double Dissociation HM & KF
Indicate that different structures in the brain are responsible for STM & LTM
Brain imaging shows us which areas of the brain are activated when we use memory
Tulving - Episodic and Semantic Memory
- Episodic - Memory for experience that have happened in the past
- Semantic - Memory for Facts
- Each handles memory in different ways
- Can be distinguished by the type of experience associated with the memory
Episodic Memory
Involves “time travel”
Reliving experiences from the past requires
Tulving says episodic memory is self knowing
Semantic Memory
- Involves accessing knowledge that is not a personal experience
- Facts, vocab, numbers & concepts
- We do not relive the past when we experience semantic memory
Patient KC - Kent Cochrane
- Severe damage to Hippocampus and Surrounds due to Motorbike Accident
- Lost ability to relive the past and imagine future
- Semantic Memory still intact
- Double Dissociation of Semantic and Episodic Memory
Levine et al. 2004
- Subjects kept audio diaries each day
- Described personal events and facts semantically
- Replaying tapes returned vivid episodic memory
- Semantic facts did not
- Evidence semantic and episodic memories activate in different areas of the brain
Semantic Memory can Influence Episodic Memory
Your knowledge of something can influence the way you experience it.
Autobiographical Memory
- Contains both Semantic and Episodic memories
- Semantic Memory is intertwined in story telling personal experiences
- People with no episodic memory don’t get enhanced memory for significant names
Autobiographical Memory - Westmacott & Moscovitch 2003
- Found knowledge of celebrities can be both Semantic and Episodic
- Participants were asked to label famous people as “know”
or “remember” - Memory was better and faster for famous people labelled
as “remember” - Autobiographical significant semantic memory
Episodic & Semantic Memory Over Time
- Recalled information is often distorted from original information
- Not simply forgetting
- Petrican et al. 2009
- Measured memories of public events over 50 years
- Asked subjects if they remember, know or
Petrican et al 2010
- Complete Forgetting was stronger after 40-50 years
- Remember responses decreased more than Know
- Episodic memory loses character over time more than semantic
- Semanticization of remote memories also occurs with recent memories
Using Memory to Think about Future
Remembering past is important for creating possible future scenarios
KS could not describe personal events that were going to happen
Addis et al 2007 - Constructive Episodic Simulation Hypothesis
- Subjects given a noun and asked to construct a past OR future event
- Once chosen, they pressed a button and elaborated for 20 seconds
- Strong overlap between areas activated during future & past events
- KC was not able to describe personal events due in the future
McDermott et al 2006 - Memory and the future
- Subjects asked to remember an event from the past or imagine a similar event in the future
- Asked to describe what they see as they went
- Were they describing in first person or third person
- Real and Imagined stories both likely to be imagined from both perspectives
- Eye levels and distance were similar across both styles
- Suggests: Episodic memory is for constructing possible future scenarios
Summary Episodic Memory
- Episodic - experiences that have occurred in the past
- Episodic memory can lose episodic nature over time
- Episodic memory can be adaptation the allows us to simulate future events
Procedural Memory
Explicit/Conscious Memory
- Episodic Memory
- Semantic Memory
Implicit/Not Conscious
- Procedural Memory
- Priming
- Conditioning
Skill Memory
- Also Procedural Memory
- Appears to be implicit - like typing or driving
- Does not require episodic/semantic memory.
- Amnesiac patients can acquire new skills though they cannot
remember learning it. - HM became quite good at the mirror drawing task
- Another patient LSJ improved at violin, though she could not
remember practising.
Procedural Memory and Attention
- Often procedural memory begins by paying close attention e.g. playing instrument
- Once mastered attending can hold back progress and performance
Expert Induced Amnesia
Often experts like musicians and sports stars cannot describe how they perform a task
Procedural Memory and Semantic Memory
- LSJ suffered Bi-Lateral Medial Lobe Damage
- Lost Episodic & Semantic Memory
- Could not identify famous artists but was an artist herself
- Could answer questions about procedural tasks about painting, music, driving
- Indicates an overlap between Semantic Processes and Procedural Memory Processes
Priming
- Presentation of one stimulus changes the way we respond to another stimulus
- Repetition Priming - when test stimulus resembles the priming stimulus
- Priming Stimulus may not be consciously available to the viewer
- Priming effects can even be seen in amnesiacs
Priming - Propaganda Effect
- Perfect & Askew 1994
- Subjects read articles with adds told don’t pay attention to adds
- Later rated adds they thought were appealing, distinctive etc
- Couldn’t remember seeing them
Summary Implicit Memory
- Includes Procedural Memory, Priming and Classical Conditioning
- Considered Implicit because we don’t need to be aware of them to influence our behaviour
- Also known as a Skill Memory
- Expertise produces Expert Induced Amnesia
- Semantic Memory Amnesia can often still have procedural memory processes because they seem to overlap
- Priming happens when we produce a stimulus and it influences response to new stimulus
Encoding & Retrieval
- Encoding is the process for information that is sent to LTM
- Retrieval is the process of extracting memory from LTM
Encoding
How do we get information to LTM?
- Maintenance Rehearsal
- Elaborative Rehearsal
The deeper the level of processing the more information is encoded
Maintenance Rehearsal
Such as repeating a phone number in your head
Elaborative Rehearsal
Remember a number by associating it with a date on the calendar
Effective Encoding - Paired Associate Learning
- Bower & Winzenz 1970
- Two words presented from a list and subjects asked to recall the second word when shown first word
- One group asked to silently repeat words from list and other group to form a mental picture
- Imagery group remembered double the words of the repetition group
Encoding Effectiveness - Self Reference Effect
- Leshikar et al. 2015
- Asked participants to look at adjectives for 3 seconds each
- Two groups were asked: Does word describe you? Is this word common?
- Suggests that words more easily remembered when linked to something people are familiar with
The Generation Effect
- Information generated about yourself enhances learning and retention
- Organising information into groups by using retrieval cues for other words
Bransford & Johnson 1972
Unorganised information is accompanied by an image that explains the information is easier to remember.
Retrieval
- How we get information from LTM in order to use it
- Two types of Recall Procedures: Free Recall and Cued Recall
- Free = subjects asked to recall stimuli
- Cued = subjects given cues to aid recall
- Cued recall generally produces better performance than free recall
Retrieval Effectiveness
- Mantyla 1986
- Participants could remeber 91% of 504 words presented to them in they self generated three retrieval cues
The Testing Effect - Karpicke & Roediger 2008
- Three groups of participants learned a list of Swahili-English word pairs.
• Phase 1: All four groups studied the pairs then tested once
• Phase 2: put into groups
• Group 1 = Studied all pairs and tested again. Three study-test trials.
• Group 2 = Correct pairs were removed from further study. All pairs tested after each study trial. Three study-test trials.
• Group 3 = All pairs were studied on each study trial. Correct pairs removed from further testing. Three study-test trials.
• Group 4 = Correct pairs were removed from further study or testing. Three study-test trials.
Encoding and Retrieval Contexts
Retrieval can be enhanced by matching conditions to those found during encoding
Encoding Specificity - words remembered in one context will be easier to remember when in the same context
Two Studies - Encoding Specificity
- Godden & Baddeley 1975 - Asked subjects to learn list of words on land or underwater; words recalled better if recalled in the same environment
- Grant et al 1998 - Words learned and recalled in either a quiet or noisy environment
State Dependant Learning
- Learning associated with internal state
- Eich & Metcalfe 1989 - memory is better when a person’s mood during retrieval matches their mood during coding
- Well researched by Nakagawa et al using animals on drugs
Transfer Appropriate Processing
- Morris et al. 1977
- Retrieval is better if the cognitive tasks are included in both encoding and retrieval
- Participants heard sentence with one word placed by blank then target word
• One group asked to answer yes/no based on the meaning of
the target word.
• One group asked to answer yes/no based on the sound of the
target word (whether it rhymed with another word).
- Subjects given a list of test words and and if the word rhymed with previous target
Encoding and Retrieval Contexts
Morris et al 1977
subjects performed a rhyming task did better in a rhyming test than those who did a semantic test
Deeper processing doesn’t always result in better retrieval
Summary Encoding
- Encoding and Retrieval describe how information gets into and out of LTM
- How effectively information is stored and retrieved by LTM is partially determined by how it was processed
Consolidation - Establishing Memories
- Consolidation - Processes that transforms new memories from fragile state to permanent state
- Synaptic Consolidation - Structural changes at synapses
- Systems Consolidation - Gradual reorganization of neural circuits within the brain
Synaptic Consolidation
- Hebb 1949
- Hebb’s Hypothesis - Neurons that Fire together Wire together
- Presynaptic Neuron repeatedly plays role in firing a postsynaptic neuron
- Enduring modification of the synaptic structure
- Long Term Potentation
- Long Term Depression
Standard Model of Consolidation
- Hippocampus appears to play an important role in memory
- Hippocampus is responsible for sending information to the cortex
- Once encoded the Hippocampus is no longer needed
- Brain Injury Studies show that loss of memory recent memory is more readily lost
Multiple Trace Model of Consolidation
- Hippocampus is involved in remembering memories that are remote in time
- fMRI shows hippocampus appear to be activated with past memories - Gilboa et al 2004
Viskontas et al 2009
- Hippocampus is not involved in every aspect of retrieval
- Participants aske to view pairs of stimuli and imagine the interacting with each other
• After 10 minutes and 1 week, participants viewed the original pair
plus novel pairs.
• Participants were asked to respond with know, remember, don’t know
• Pairs that remained episodic after 1 week activated the hippocampus,
but not the pairs that became semantic.
• After 10 minutes and 1 week, participants viewed the original pair
plus novel pairs.
• Participants were asked to respond with know, remember, don’t know
• Pairs that remained episodic after 1 week activated the hippocampus,
but not the pairs that became semantic.
Consolidation & Sleep
- Sleep enhances consolidation - Gais et al 2006
- Wilhem et al 2011 - Participants who were told that they would be tested performed better after a sleep
Reconsolidation
- Memories need to be updated to adapt to new environment
- When memory is retrieved it becomes fragile
- Needs to be consolidated again
- This allows memory to be forgotten or modified
Reconsolodation - Nader et al 2000
Reconsolidation - Hupback et al 2007
• Asked two groups of participants to remember a list of 20 objects.
• After two days, one group of participants were asked to remember the
procedure from two days prior. They were not asked to recall any of
the objects.
• They were then asked to memorise a second list of 20 objects.
• After two more days, participants were asked to recall the first list.
• The second group received identical treatment but were not asked to
remember the procedure.
Reconsolidartion - Temporal Context Model
Reminder group learned the second list in same context as first
No Reminder group learned second list in new context
Second list may have been associated with context leading to errors seen in reminder group
Paired Associate Learning
- Remembering two stimulus that are paired together
- Found paired words were easier to remember when own knowledge and own imagery used
- Least successful when using rehearsal only
- imagery remembered better because we use Multiple Modalities using visual memory and semantic memory
Encoding Specificity
- remembered words can be encoded with meaning
- We can remember verbatim and related meaning cues
- don’t need to memorise a subject but better to understand meaning and context and relationships
Memorising and Encoding Specificity
- If we rely too heavily on memorising or specific cues memory is poorer
- Best to study meaning and relationships than memorise exact wording
What is Encoding Specificity Principle
We retrieve information better when we retrieve it from the same context in which we learned it
What is Long Term Memory
Not just about retaining information from the past
Interacts with STM & Working Memory to create our conscious experience
Semantic Coding in Memory
- It is not just verbatim words that encode into STM
- Wickens found that Proactive Interference caused later lists of words to be remembered less
- The meanings of words get encoded into STM
- When last list changed from professions to fruits rememberd words rose
- This is because the meanings of the professions did not interfere with the names of fruits.
Sachs 1967 Galileo Passage
- People do not remember the specific wording of things they have read in Long Term Memory
- They mostly remember the general meaning of the passage
- If the words are all there but in different order they could misidentify the correct sentence
Rangarath & D’Esposito 2001 - Novel & Familiar Faces
- When sample faces were new subjects showed increased hippocampal signal activity
- When sample faces were familiar the signal change was lesser
- Evidence that hippocampus is connected to maintaining new information in the STM
Levine et al 2004 - Brain Imaging & Episodic/Semantic Memory
- Subjects kept audio diaries describing day to day events and certain facts about their day
- When listening again episodic events lit up parts of brain associated with episodic memories
- Semantic facts did not light up the same parts of the brain as the episodic ones.
Memory and the Future
- Remembering the past is important for creating future events
- Constructive Episodic Simulation Hypothesis
- Episodic memories are combined to build a simulation of any future events
Imagery helps with Encoding
- Paired Associate Learning
- When we self generate an image of remembered words they are easier to recall
Self Reference Effect
Leshikar et al 2015
People remember words better when they can make it personal
Generation Effect
Information that is self generated is more easily remembered
Bransford & Johnson 1972
- When Information is organised better, it is remembered batter
- An image can make a passage make sense and then is more easily remembered
Survival Value Words - Nairne 2010
When we relate words to survival it enhances the encoding value
Is now remembered more easily
Evolutionary Psychology
- Branch of Psychology
- Almost proved but did not do additional research beyond those that supported the Theory
- Humans evolved to specifically deal with information they might need to survive in
- Cognition is enhanced in these situations
- Hypothetical Survival Techniques e.g. zombie attacks
- Survival Value Effect
Karpicke & Roediger 2008 - Testing Effect
- Four groups learning Swahili-English words
- Testing long term encoding effect after one week delay all groups tested on all words
- Both groups that were tested each time scored high after 1 week delay
- Being tested on material improves recall on material even if subjects study less
Encoding Specificity - Godden & Baddeley 1975
- Information can be retrieved more easily by matching conditions found in encoding
- e.g. smelling perfume, or chewing gum
- grant et al 1998 - Noisy or quiet environment; matching environments tested better than not
State Dependent Learning
- Learning associated with internal state
- Memory is better when mood during retrieval is the same as when learning/encoding
Transfer Appropriate Processing
- Subjects heard a sentence one word replaced by blank, then target word
- Asked ye/no based on either meaning or rhyming
- Rhyming had better outcomes than semantic group
- Deeper processing doesn’t always result in better retrieval
Consolidation
- What is going on in the brain when we establish memories in it
- Synaptic Consolidation
- Systems Consolidation
- Neurons actually change their form to increase the consolidation process
Rest and Consolidation
- If we don’t take a break or sleep new information is harder to remember
- Sleep allows us to process consolidation
- People who know they are gonna be tested consolidate information better than those who don’t
- Means we can selectively consolidate information we want to remember
Neurons that Fire Together Wire Together
Memories are not just neurons firing together but a pattern of neurons firing together
When we consolidation memory there is a structural change in the neural network between synapses
This stabilises the memory and helps us recall it later on
Reconsolidation
Used to update memories that become fragile
Nader et al 2000a - Reconsolidation
- Used drug Anisomycin to block memory of pain in mice which inhibits protein synthesis
- This drug blocks the synapses from changing and consolidating memory
- Maybe Anisomycin produces amnesia not extinction of a particular memory
