Forgetting

Question 1

What are the different types of forgetting?

Answer 1

· Incidental forgetting
- Occurs without the intention to forget
· Motivated forgetting
- Purposefully diminish access to memory (e.g. unwanted memories)

Question 2

What is a superior autobiographical memory?

Answer 2

• Uncontrollable remembering
• Feels as though the person relives the events they remember
• Remembering is ‘automatic’, effortless and not under conscious control
• Cannot forget unpleasant memories
• Memories can be distracting

Question 3

What is the forgetting rate?

Answer 3

• Forgetting increases as time progresses BUT the rate of forgetting is deferent
• Ebbinghaus studies on forgetting
• Forgetting curve
  § Logarithmic relationship
  § Forgetting rapid initially
  § Less additional forgetting at longer intervals

Question 4

What is the distinction between availability and accessibility?

Answer 4

• Recall is generally worse after delays than recognition -> a distinction should be made between:
• Availability
  § Is the item in memory store? (this item may not have a memory trace any more)
• Accessibility
  § Is the item accessible for retrieval? (the item may be stored but not accessible
• Both may denote forgetting

Question 5

What are factors that discourage forgetting?

Answer 5

• Better learning at the beginning
• Repeated attempts to retrieve – (testing effect/ generation effect) builds up resistance to forgetting (e.g., Linton, 1975)
  § Recalling an event reduces the rate of forgetting
• Incomplete or inaccurate retrieval may lead to memory distortions
• Not all memories are equally vulnerable to forgetting at all points in their history (forgetting curve)

Question 6

What is Jost’s law?

Answer 6

§ All else equal, older memories are more durable and forgotten less rapidly than newer memories
§ New memories are initially more vulnerable to disruption/ distortion until they are consolidated

Question 7

What is consolidation?

Answer 7

• Consolidation: The process that transforms new memories from a fragile state, in which they can be disrupted, to a more permanent state, in which they are resistant to disruption

Question 8

What is synaptic consolidation?

Answer 8

§ Structural changes in the synaptic connections between neurons
§ May take hours – days to complete
§ Memories are vulnerable until these changes are complete

Question 9

What is systems consolidation?

Answer 9

§ Gradual shift of memory from hippocampus to the cortex
§ Memory components (in the cortex) are replayed until they are linked
§ May take months – years to complete
§ Memories are vulnerable for as long as they rely on hippocampus

Question 10

What is trace decay?

Answer 10

• Memories weaken due to passage of time

Example: facts you learned in school fade out of memory

Question 11

What are context shifts?

Answer 11

• Different cues are available now than the ones available at encoding
• Example: school is a completely different context than now

Question 12

What is interference?

Answer 12

• Similar memories hinder retrieval

- Example: After a biology lecture you forgot what you learned in chemistry an hour before

Question 13

What types of memory are especially prone to trace decay?

Answer 13

§ Priming and familiarity especially prone to decay

Question 14

How does decay affect memories?

Answer 14

§ A memory’s activations fade, but the memory itself is intact (stored and available but inaccessible)
§ OR
§ The memory itself and its elements (i.e., its associations) degrade along with its activity level

Question 15

What is the biological basis of trace decay?

Answer 15

• Synaptic connections degrade and neurons die as time goes by -> memories may die or fade in the same way
• The opposite biological mechanism may also explain decay (Frankland et al., 2013)
  § Neurogenesis (growth of new neurons – especially in hippocampus) means that the structure is remodeled and its connections are gradually modified
  § Good for new learning – generation of new associations
  § Bas for older memories retained in hippocampus

Question 16

What is the validity of trace decay?

Answer 16

• Behaviourally it is difficult to prove trace decay
• Two important factors cannot be controlled when attributing forgetting to decay:
  § Rehearsal
  § Interference from new experiences/ memories
• Memories unavailable or simply inaccessible?

Question 17

What are alternative factors of incidental forgetting?

Answer 17

• Correlates of time
  § Forgetting may not be caused by the passage of time itself but by a correlate of time
• Contextual fluctuation (correlate of time):
  § Similarity between encoding and retrieval context may explain forgetting
  § Incidental context differs more between retrieval and encoding over time
  § Incidental context is less similar to the remote past than more recent past
• Interference
  § Similar traces/ memories impede retrieval
  § It is difficult to discriminate between them
  § Similar memories accumulate more over time
  § Whenever the cue that can be used to access a memory becomes associated with other memories

Question 18

How does interference work?

Answer 18

• Competition assumption: memories associated to share cue automatically impede retrieval when the cue is presented
  § A cue activates all associates (more or less)
  § The activated associated compete for access to consciousness
  § Competitors hinder access to target memory
• Interference occurs due to the negative effect of having competitors
  § It increases with the number of competitors a target memory has

Question 19

What is retroactive interference?

Answer 19

If the target memory is based before a new memory

• Introducing a new (second) memory impairs recall of a first memory (especially similar)
• Especially strong interference if the two lists share cues
• More training on the second list results in more first list impairment
• Not every type of intervening experience impairs memory – the experience needs to be similar

Question 20

What is proactive interference?

Answer 20

If the target memory is placed after a new memory

• The tendency of older memories to interfere with retrieval of recent experiences and knowledge
• The number of previous learning experiences (e.g. lists) determine the rate of forgetting of new ones
  PI is more severe for recall than recognition

Question 21

What is part set cueing impairment?

Answer 21

• The tendency for recall to be impaired by the provision of retrieval cues drawn from the same category of items in memory
• Providing hints may impede memory retrieval
• The impairments is more sever with increasing numbers of cues provided from the same set
• Presenting similar items as cues, strengthens their association to the cue
• Competition for non-cues increases -> memory worsens

Question 22

What were the results of Slamecka’s part set cueing study?

Answer 22

providing cues (i.e. competitor items) reduced recall for the non-cued items (i.e. targets)

Question 23

What is retrieval induced forgetting (RIF)?

Answer 23

• Selective/ partial retrieval can harm recall of other memories related to the retrieved item
• Compared to baseline items for which no related items had been retrieved
• This has important implications for learning and studying
• Selective retrieval may contribute to more severe forgetting for information that is not practiced/ retrieved

Question 24

What does retrieval induced forgetting (RIF) have implications for?

Answer 24

RIF may have important implications for how witnesses should be questioned

Question 25

What is the associative blocking mechanism for interference?

Answer 25

• Description: a cue fails to elicit a target trace because it repeatedly elicits a stronger competitor, leading people to abandon efforts to retrieve target
• Examples:
  § Tip-of-the-tongue: keep coming up with incorrect response
  § RI: cues elicit 2nd list blocking 1st
  § Part-set cuing: exemplar cues keep intruding
  § Cue overload: more associates, more likely a wrong answer to intrude

Question 26

What is the associative unlearning mechanism for interference?

Answer 26

• Description: associative bond linking a stimulus to a memory traced is punished by weakening it after being retrieved in error. Difficult to demonstrate empirically
• Examples: RIF & RI: competitors intrude at retrieval practice and are punished
  The mechanisms are not mutually exclusive

Question 27

What is inhibition?

Answer 27

• Inhibition: It allows an unwanted response to be stopped, while an alternative response needs to get strengthened
• E.g., recalling your old number when asked for telephone number (PI) – inhibition predicts that gradually old number will be inhibited to allow for new number
• Unlike blocking mechanisms, inhibition suggests that forgetting targets the memory itself (not its association to the cue)

Question 28

What is the functional account of forgetting?

Answer 28

• Forgetting -> to control retrieval in the face of competition
• May serve a functional purpose and therefore can also be an active process
• Facilitates future retrieval attempts of practiced/ strengthened memories by inhibiting competitors
• In this sense forgetting is beneficial
• Serves goal directed behaviour and decision making

Question 29

What does forgetting promote?

Answer 29

· Forgetting promotes flexibility and generalisation – Richards & Frankland, 2017

• Memory should not be viewed as a means for high fidelity transmission of information
• The goal of memory is to guide intelligent decision making
• Forgetting allows individuals to exhibit flexible behaviour and generalise past events to new experiences
• From this perspective, forgetting is not necessarily a failure of memory
• It may represent an investment in a more optimal mnemonic strategy

Question 30

What is the summary of forgetting?

Answer 30

• More forgetting initially but less additional forgetting at longer intervals
• Consolidation makes memories more resistant to forgetting – synaptic (early) and systems (late) consolidation)
• Theory of decay over time
• Apart from decay, other factors may contribute to forgetting – synaptic (early) and systems (late) consolidation
• Theory of decay over time
• Apart from decay, other factors may contribute to forgetting: context shifts, interference
• Retroactive interference and proactive interference
• Retrieval induced forgetting: remembering can cause forgetting
• Part set cuing: when part of set is presented disrupts retrieval of the remaining
• Forgetting can be adaptive in order to increase cognitive efficiency