Memory

Question 1

Memory - definition

Answer 1

Memory is the process of maintaining information over time. Memory is an active system that receives, stores, organizes, alters and recovers information

• memory is the base of all cognitive activities
• It functions to preserve our sense of self, maintains our interpersonal relationships and helps us in solving problems and taking decisions

Question 2

Stages of memory

Answer 2

Memory is conceptualized as a process consisting of three independent, though interrelated stages. Any information received by us necessarily goes through these stages

1. Encoding
2. Storage - Process through which information is retained for a period of time
3. Retrieval - Bringing stored information into awareness

Question 3

3 stage model of memory - names

Answer 3

Atkinson and Shiffrin 1968

Question 4

Levels of processing model - names

Answer 4

Craik and Lockhart 1972

Question 5

Multi store model - Intro

Answer 5

Atkinson and Shiffrin gave the information processing model based on the analogy of human memory to computer storage system.

According to the model, there are 3 stores of memory. These are not mini- warehouses. They are different types of memory systems with different characteristics
1. Sensory memory 2. STM 3. LTM

Diagram

Question 6

Evaluation of multi store model

Answer 6

Strengths

1. The model has been influential and has directed a lot of research in memory, which have refined our understanding of memory
2. Many studies provide evidence to support distinction between STM and LTM
3. The model is supported by study of amnesiacs - e.g. HM

Weaknesses

1. The model is oversimplified - e.g. Research into working memory (Baddelley and Hitch) has shown that STM is more than just a simple unitary store
2. Even LTM is not a unitary store but is shown to have components like episodic memory, semantic memory and procedural memory
3. Shallice and Warrington in 1970 cited case of KF whose STM was seriously affected due to an accident but LTM is intact, which shouldn’t be possible according to stage model

Question 7

Sensory memory

Answer 7

The information acquired from environment via sense organs is put here briefly.

Each sense organ has their separate store

Whatever our sense organs sense, it’s in sensory memory, but we aren’t consciously aware of it and whatever we pay attention to is shifted to STM and our consciousness

Sperling’s experiment - partial report method, delay in auditory cue

Function of iconic memory - It helps us see the world around us as continuous and stable. It allows the brain enough time to decide if information is important enough to bring into consciousness

Question 8

Encoding in STM

Answer 8

Dual coding hypothesis - Phonological coding and Visual coding (proposed by Paivio)

More often, memories in STM are done in phonological coding (i.e. talk in our heads). Visual coding is used when we store concrete nouns or objects (e.g. Eiffel tower)
- Imagine fitting clothes into a suitcase - we use visual coding for this. But even then, we have a dialogue going on

More concrete things(e.g. bird) are encoded using visual coding and abstract things (e.g. truth, honesty) are encoded using phonological coding

Question 9

Storage capacity in STM

Answer 9

George Miller - digit span test - magic number 7 - storage capacity - 7+/-2

• We can remember more than 7 digits( e.g. 10 digit phone number) using a method called chunking
  
  • The bits of information can be combined into meaningful chunks e.g. 9848 320 640. Instead of 10 digits, we remember 3 chunks
  • Connecting the information to information in Long term memory
    
    • e.g. YGOLOHCYSPDUTS is almost impossible to remember. But. once we know it’s study psychology in reverse, a connection to LTM can be made and it can be remebered easily
    • Experts remember chess board positions better than novices (by linking it to LTM)
  • This way, we can expand STM storage to 7+/- 2 chunks

Question 10

How does chunking work?

Answer 10

Chunking reorganizes i.e. recodes information into units that are already in LTM. This connection makes it easier to remember chunks

Question 11

Effect of length of chunks

Answer 11

• STM can hold fewer words when they take longer to say
  
  • e.g. The span is less for words like harpoon, cyclone etc. than it is for cat, pen etc.
• This happens because longer words take longer time to say and by the time we get past first few, the rest fade before they can be recalled

Question 12

How long can we store info in STM

Answer 12

STM lasts for about 12-30 seconds without rehearsal. After that, memory starts to rapidly decay or disappear (Atkinson and Shiffrin)

To prevent decay, we should do maintenance or elaborate rehearsal

• Maintenance rehearsal works because by repeating, we are constantly paying attention to it and as long as we do it, it stays in STM. When we are distracted and don’t pay attention, it’s rapidly lost (e.g. counting a stack of notes)
• –This also explains the limit of 7. We have a limited attention and can attend to only about 7 items at once

Question 13

Retrieval from STM

Answer 13

STM is thought of as consciousness; So, information in STM is there, we can just retrieve it

How long does retrieval take? directly proportional to no. of items (Experiment by Sternberg) - draw a graph

Question 14

Transfer from STM to LTM

Answer 14

Through consolidation

• It could happen through Maintenance rehearsal (inevitable in some cases e.g. memorizing phone no. or bank account)
• It could also happen through elaborative rehearsal i.e. making the information meaningful by connecting new information with something already known

Serial position effect

Question 15

Serial position effect

Answer 15

Free recall experiment by Murdock
Participants see a list of 40 unrelated words and they can later recall them, in any order. The results of recall are (Serial postion effect)

At the time of recall, the last few items would still be in STM and thus are better recalled. It is called recency effect

• But, first few words are also well recalled, called primacy effect
  
  • Why does it occur? When first were were presented, they enter into STM, which is relatively empty and are rehearsed often, causing transfer to LTM. As more items were presented and STM filled up, the no. of rehearsals for each item fell down and they didn’t transfer to LTM

Question 16

Reconstructive nature of memory

Answer 16

Unlike a CD, memory is a constructive and a reconstructive process. Remembering is like problem solving, where we have to give a coherent account of something that happened with whatever bits we could remember and filling in the rest

• Each time a memory is retrieved, it may be altered or revised in some way to include new information or to exclude details
• One example is hindsight bias i.e. the tendency to falsely believe, through revision of older memories to include new information, which could have correctly predicted the outcome
• Memory reconstruction can be due to internally reconstructed process or externally provided suggestions
  
  • Internal - We often use our schemas i.e. mental representation of a class of objects, people or events in reconstruction. If our memory does not fit our schema, we might engage in reconstructing the memory in a manner that it will align with our schema. All of this happens automatically and without conscious effort
    
    • Bartlett’s ‘war of ghosts’ study
  • External - Loftus experiment
    
    • Information that comes in an entirely different format can also alter memories (original - film, later - word)

Question 17

Levels of processing model

Answer 17

This model focuses on the depth of processing involved in memory, and predicts that the deeper information is processed, the longer a memory will last

• The strength of memory depends on the depth in which the information is processed
  
  • Craik defined depth as “the meaningfulness extracted from the stimulus rather than in terms of the number of analyses performed upon it.”
• Unlike multi-model theory, it is a non-structured approach. Instead of concentrating on the stores or structures involved, this theory focuses on the processes involved in memory formation

Information can be processed in two ways - shallow and deep

Information that is processed using deep processing is remembered better than information that is processed using shallow processing
– Craik and Tulving study

Question 18

Analysis of levels of processing model

Answer 18

Strengths

• It is an improvement on Multi store model of how information moves from STM to LTM
• It showed that encoding is not a simple, direct process and made LTM to be viewed as an active system rather than a storage space
• It can be used in everyday lives to aid memory

Weaknesses

• It does not explain how deeper processing results in better memories
• Deeper processing takes more effort than shallow processing and it could this that is responsible for better memory rather than deep processing
• The concept of depth is vague and cannot be measured

Question 19

Retrograde Amnesia

Answer 19

• The type of amnesia where there is a loss of memory from the point from the point of injury backwards
• When people receive a head injury, they are often unable to remember the accident itself
• They might lose hours, days or years before the accident
• It happens due to the disruption in consolidation; leading to all the memories that haven’t been consolidated yet getting lost
  
  • Consolidation could sometimes take days or even years to be completed
  • e.g. computer has auto save every 10 minutes. Power loss ⇒ last few minutes work gone
• When electroconvulsive therapy (ECT) is given to patients suffering from severe depression, they seem to forget previous memories

Question 20

Anterograde amnesia

Answer 20

• The loss of memories from the point of injury forward
• People with this amnesia, like HM have difficulty remembering anything new. They cannot form any new declarative memories.
• —In case of concussions, it will be temporary
• The non-declarative memories are largely preserved
• People with dementia often suffer from this kind of amnesia. Alzheimer’s is a form of dementia
• This can lead to old people taking a dose of medicine several times because they couldn’t remember taking it
• It will also lead to repeated conversations and the same question being asked again and again

Question 21

Infantile amnesia

Answer 21

We usually can’t remember anything that happened before 3 years of age

• Why?
  
  • Early memories are usually implicit and are difficult to bring into consciousness
  • Explicit memory, which is more verbal does not develop until age 2, when the hippocampus is fully developed and language skills blossom
  • Even if we have memories from that age in LTM, we probably cannot retrieve them as the encoding would be completely different

Question 22

Ebbinghaus and forgetting curve

Answer 22

First researcher - 1885
He memorized a list of nonsense words (e.g. bek, gach etc.) and tried to recall them. His performance resulted in this famous graph

• Most of what he learned was forgotten in the 1st hour only
• But, more meaningful content won’t be forgotten so quickly or completely, but broadly follows the same pattern

Question 23

Theories of forgetting

Answer 23

1. Encoding failure - We fail to encode memory (not so much forgetting)
2. Memory trace decay theory
3. Interference - Proactive and retroactive
4. Retrieval failure

Question 24

Memory trace decay theory

Answer 24

Also called as disuse theory

The assumption here is that memory leads to modification in CNS, which is akin to physical changes in brain called memory traces
-Over time, if memory traces are not used, they may decay, fading into nothing
-Forgetting in sensory memory and STM is easier to explain using this theory
For LTM, sometimes memories that are taught as lost are recalled
— It also fails to explain why memory improves after sleep when memory traces are not used

Question 25

Interference

Answer 25

Information in LTM may not always be accessible because other information interferes

Interference theory assumes that learning and memorizing involve forming of associations between items. Interference comes during retrieval when various sets of associations compete with each other for retrieval

1. Proactive interference
   - - The tendency for older or previously learned material to interfere with the learning and retrieval of new material
2. Retroactive interference
   - - Difficulty in recalling old information because newer information interferes with older information, it is called retroactive information

Phone example - new phone, old phone

Question 26

Retrieval failure

Answer 26

Forgetting can happen due to there being inadequate retrieval cues during recall
- Retrieval cues help us in recovering memory

examples - tip of the tongue phenomenon, state dependent learning etc.

Question 27

Working memory - Intro, importance

Answer 27

Working memory is a later conception of STM

Working memory theories assume that complex reasoning and learning tasks require a mental workspace to hold and manipulate information

Baddeley and Hitch suggested that STM is not a passive storehouse but rather a workbench that processes the information in STM as people perform various cognitive tasks

• It is important for reasoning, learning and comprehension

Question 28

Evaluation of working memory

Answer 28

Strengths

• Researchers generally agree that STM is made up of a no. of subsystems
• The working memory model explains a lot more than multi store model and is supported by considerable evidence
• Working memory is supported by dual task studies of Baddeley and Hitch
• It doesn’t over-emphasize the importance of rehearsal for STM retention, in contrast to multi store model

Weaknesses

• Visuospatial sketchpad implies that all spatial information was first visual. Blind people actually have great spatial awareness, without any visual information
• There is little evidence for how central executive works and what it does. It’s capacity has never been measured
• Working memory model doesn’t explain changes in processing ability as a result of practice or time

Question 29

Neuroscience of memory

Answer 29

Different types of memories are stored in different areas of the brain

1. Procedural memories - cortex and temporal lobe
2. STM - prefrontal cortex and temporal lobe
3. Declarative - frontal and temporal lobes, but not in same place or location as STM
4. Fear - amygdala

Hippocampus and Memory

• H.M was having seizures and his surgeon removed hippocampi and adjacent temporal lobe structures in an experimental operation to reduce seizures
• This loss of both hippocampi severely impaired his ability to form new declarative memories.
• He was unable to consolidate and store any new information he encountered; but his procedural memory was intact

Question 30

Techniques to improve memory

Answer 30

1. Imagery
2. Elaboration i.e. deep processing
3. Practicing retrieval - rather than re-reading
4. Organization - Organizing knowledge into a story helps with memory
5. Mnemonics
6. Knowledge base - Knowing more about a topic makes new information more meaningful and easier to remember
7. Spacing to minimize effect of interferences - distributed study is better than cramming
8. Making a rhyme
9. Minimizing interference - not learning similar material one after another

Question 31

Properties of LTM

Answer 31

• The capacity of LTM is unlimited for all practical purposes
• Memories last for a long time; though they may not be accessible due to retrieval failure
• Not all memories are stored forever. Only events and concepts that are meaningful to us

Question 32

Encoding in LTM

Answer 32

• For verbal material, the dominant representation is semantic (meaning)
  
  • Encoding semantically occurs more prominently when it is in sentences. We remember the crux of sentence, but not the exact words
  • Semantic encoding is even more pervasive in everyday situations. When people report on complex social or political situations, many specifics are misremebered, but the basic situation is accurately remembered
• Although meaning is dominant, we can sometimes code other aspects as well. We can memorize songs or peoms and reproduce them word to word
• We can also use phonological code for certain things e.g. songs, recognizing other people’s voices
• So, while meaning is prominent, other forms of encoding is also used

Question 33

How is memory organized in LTM

Answer 33

• LTM needs to be fairly organized to be able to retrieve information quickly

Research suggests that LTM is organized in terms of related meanings and concepts (Collins and Loftus).

In their original study, subjects had to respond true or false to statements like “a canary is a bird”, “a canary is an animal”
-To verify canary is a bird requires moving only one node whereas to verify canary is an animal, one should move 2 nodes and takes longer

Based on this, they gave the semantic network model

Question 34

Semantic network model

Answer 34

Given by Collins and Loftus - based on their study

It assumes that information is stored in a connected fashion, with concepts that are related stored closer to each other than concepts that aren’t

Nodes diagram

Question 35

Parallel distributed processing model

Answer 35

Although nodes in a particular category (e.g. animal) are activated in a serial fashion, nodes across the entire network can be activated in a parallel fashion

• Parallel Distributed Processing Model (Rumelhart) can be used to explain how rapidly different portions of networks can be accessed
  
  • It says that memory processes take place at the same time over a large network of neural connections
  • This also means sensory, STM, LTM don’t need to happen in a serial fashion
• Parallel Distributed Processing model is related to ‘connectionism’ in AI. i.e. use of artificial neural networks to explain the mental abilities of humans

Question 36

Automatic encoding

Answer 36

• Many times, we make no effort to put information in LTM, but it happens automatically
• Memories of highly emotional events can often seem vivid and detailed, as if the person’s brain took a flash picture of that time. These memories are called flashbulb memories
  
  • They seem so vivid because emotional reactions release hormones which aid the formation of LTM
  • Flash bulb memories are no more accurate than normal ones, but people believe that they are

Question 37

Recall and recognition

Answer 37

They are 2 kinds of retrieval of memory. In recall, memories are retrieved with few or no external cues. In recognition, we look or har information and try to match it to what is already in memory

• With recall, we experience ‘tip of the tongue’ phenomenon, where the answer seems like it’s on the tip of the tongue but often eludes us
• Serial position effect

Recognition

• It is much easier than recall because the cue is the actual object one is trying to detect as familiar and known e.g. MCQs, T/F etc.
• Recognition for images, especially human faces is very accurate
• Recognition is often hampered by false positives, where we think we recognize something, but in fact, it was never in the memory

Question 38

Encoding specificity

Answer 38

While committing something to memory, almost anything in one’s surroundings can become a cue; which will aid in retrieval later

This connection between surroundings and remembered information is called encoding specificity

3 types of encoding specificity

1. Context dependent learning - swimming pool experiment
2. State dependent - Along with physical surroundings, our physiological and psychological states also become cues
3. Mood dependent - In an experiment (Eich and Metcalfe), participants’ mood was altered through music (sad or happy music) and they were asked to remember a list of words and they were able to recall much better if they were in same mood rather than a different one

Question 39

Retrieval from LTM

Answer 39

Memories need to be retrieved from LTM to working memory.
For better retrieval, Elaborative rehearsal is better than maintenance rehearsal because elaborate rehearsal gives you a semantic cue along with a verbal cue to recall whereas maintenance rehearsal only gives you a verbal cue
- The more retrieval cues there are, the better recall

Concepts - Encoding specificity, interference, retrieval cues

Question 40

Types of memories in LTM

Answer 40

Declarative(Explicit) and procedural(Implicit)
– Declarative is split into semantic and episodic

Use diagram

Question 41

Declarative vs procedural

Answer 41

Declarative

1. Knowing what
2. Episodic (events experienced) and Semantic (Facts, GK)
3. All information pertaining to facts, names, dates, such as rickshaw has 3 wheels or frog is an amphibian etc.
4. Formed and stored in Hippocampus

Procedural

1. Knowing how - relates to procedures for accomplishing various tasks and skills
2. Includes Motor skills, habits - skills like swimming, riding a bike
3. They are not forgotten even by people with Alzheimer’s or amnesia
4. These memories can be fully expressed only as actions and it’s difficult to describe them
5. Formed and stored in Cerebellum
6. They may or may not be in conscious awareness

• Implicit memory is called so because the fact that memory exists is implied by the ability to do the thing e.g. swimming

Question 42

Semantic vs episodic

Answer 42

This distinction is proposed by Tulving

Semantic

1. Memory contains facts and knowledge of language and information learned in formal education
   e. g. meanings of words, spellings, concepts, math skills etc.
   e. g. What is the capital of France?
2. Unlike episodic memory, semantic memory is not dated. i.e we won’t be able to tell when we learned the capital of France
3. It is affect neutral

Episodic

1. Memory contains personal experiences and it’s contents are generally emotional in nature e.g. How did you feel when you got 1st rank?
2. They tend to be updated and revised constantly
3. Meaningful memories are more likely to be stored for a long time

Question 43

Tower of Hanoi experiment

Answer 43

Useful in anterograde amnesia answer

In an experiment by Cohen et al, patients with anterograde Amnesia were taught to solve ‘Tower of Hanoi’

- In anterograde amnesia, hippocampus is damaged and now new long term declarative memories cannot be formed
- The patients didn't remember learning how to solve it. Each trial was like first trial
- Yet, they could solve the puzzle even though they claimed they have never seen it before
- They may not be able to explain how they acquired new skills, but they can still do them

Question 44

Context dependent learning experiment

Answer 44

Goddon and Baddeley - Context dependent learning (swimming pool experiment) (1975) - showed that divers recalled words better when the recall condition matched original learning environment

Question 45

Important Researchers

Answer 45

1. Atkinson and Shiffrin - Multi store model (1968)
2. Craik and Lockhart - Levels of processing theory (1972)
3. Miller - storage capacity of STM (1956)
4. Sperling - Partial report method for determining size of iconic memory (1960)
5. Paivio - Dual coding hypothesis
6. Baddeley and Hitch - Working Memory (1974)
7. Ebbinghaus - Forgetting curve (1885)
8. HM - Anteregrade amnesia patient
9. Sternberg - Experiment to study retrieval from STM. More items → more time (1966)
10. Murdock - Free recall experiment (serial position effect) (1962)
11. Cohen et al - Hanoi tower experiment on patients with anterograde amnesia to show implicit memory and explicit memory are stored in different places
12. Collins and Loftus - Semantic network model (1975)
13. Rumelhart and Mclelland- Parallel distributed processing model (1980s)
14. Goddon and Baddeley - Context dependent learning (swimming pool experiment) (1975) - showed that divers recalled words better when the recall condition matched original learning environment
15. Elizabeth Loftus - Impact of external suggestions on memory recall (misinformation effect) (1975)
16. Bartlett - War of Ghosts study (1932)
17. Shallice and Warrington - case of KF whose STM is damaged but LTM is intact
18. Craik and Tulving - Participants who semantically processed words recalled them better (1975)

Question 46

Shallow vs Deep processing

Answer 46

1. Shallow Processing
   
   1. Structural processing ( Appearance)
      
      • When we encode only the physical qualities of something
      • e.g. the typeface of a word
   2. Phonemic processing (sound)
      
      • When we encode only sound
        They only involve maintenance rehearsal and leads to short term retention
2. Semantic processing (meaning) - deep processing
   
   • When we understand the meaning and relate it to what we already know
   • It involves elaboration rehearsal which involves a more meaningful analysis and leads to better recall
   • e.g. Thinking of ‘cat’ as an animal that has fur, four legs, a tail and a mammal. One can also invoke an image of a cat and connect that image with one’s experiences

Question 47

Craik and Tulving study

Answer 47

Participants who semantically processed 60 words performed better at picking the words out of 180 words compared to participants who who processed them structurally
– Deep processing leads to better memory

Question 48

Meta-memory

Answer 48

It refers to people’s beliefs about their memory and how people monitor and control their learning and memory

• Modern research on this topic is based on the assumption that one’s understanding of one’s own memory guides one’s behavior
  
  • e.g. A student who believes that he has mastered the content for upcoming exam may cease further study
• Findings from research on meta-memory have significant implications for theoretical approaches to learning and understanding of self-regulation
  
  • They also have applications in variety of field settings, such as within education and eyewitness testimony

Question 49

Working memory v/s STM

Answer 49

The shortcomings in the conception of STM are addressed in working memory

• According to Multi store model, STM holds limited amount of information for short periods of time with little processing
• Researchers( Baddeley and Hitch) argued that this conception of STM is far too simplistic
• Whereas STM can only hold information, working memory can both retain and process it

Question 50

Components of working memory

Answer 50

3 components

1. Visuospatial sketchpad
   
   • This is where we store visual images through visual coding in STM
   • It is used for navigation
2. Phonological loop
   
   • It has both speech perception (hearing) and speech production (inner voice) elements in it
   • It also deals with both spoken and written material
3. Central Executive
   
   • It controls the other two systems and acts as interpreter for both the visual and auditory information
   • The central executive helps interpret the information from both systems and pulls it all together
     
     • e.g. When watching a movie, what we see is in visual sketchpad and what we hear is in phonological loop and central executive helps us combine them both to understand the scene on screen
   • It allocated attentional resources to be distributed to various information needed to perform a cognitive operation
   • It deals with cognitive tasks such as mental arithmetic and problem solving

Baddeley later added episodic buffer as a third store to explain findings that the original model failed to
–Episodic buffer acts as a ‘backup’ store which communicates with both long-term memory and the components of working memory.

Question 51

Semantic network model vs Parallel Distributed Processing model

Answer 51

Semantic network model explains how information is stored in a connected manner and PDP model explains how we move to different points at great speed

• Moving between networks with ease is difficult for AI. That’s why they can’t pass Turing test. Humans can move across topics of conversation seamlessly. It is not so easy for machines