Lecture 4: Types of Forgetting Flashcards
What is incidental forgetting?
This occurs without the intention to forget
What is motivated forgetting?
Purposefully diminishing access to memory (i.e., unwanted memories)
What is superior autobiographical memory?
Uncontrollable remembering, it feels as though the person relives the events they remember - not under conscious control.
Cannot forget unpleasant memories.
Do we forget at a constant rate over time?
No, while forgetting does increase as time progresses, the rate of forgetting is different.
What is the forgetting curve?
Proposed by Ebbinghaus. It has a logarithmic relationship, meaning it is rapid initially. There is less additional forgetting at longer intervals.
Meeter et al., 2005 conducted a study on forgetting public events, what did this study conclude?
The results were similar to Ebbinghaus’ forgetting curse. Recall had a steep initial drop, followed by a slower forgetting rate. Recall for EVENTS dropped from 60% to 30% in a year. The recognition for the same effects was less affected.
Bahrick et al., 1975 conducted a study on forgetting personal events [recall and recognition of classmates after delay of up to 30 years], what were the results?
That recognition of classmates’ faces/names remained intact; match up names with faces was also unimpaired. However, the recall of a name when given a person’s pictures was extensively impaired [rate of forgetting was similar to Ebbinghaus’ forgetting curve]
Bahrick then conducted a second study in 1984 aiming to explore forgetting again after a delay of 2 years, what were the results?
Forgetting levels out after a period of 2 years, and there is little forgetting after this period.
We know that recall is generally worse after delays than recognition, what distinction should be made?
Between availability and accessibility - BOTH DENOTE FORGETTING
What is availability?
Is the item in memory store? The item may not have a memory trace
What is accessibility?
Is the item accessible for retrieval? The item may be stored but not accessible.
What factors discourage forgetting?
> Better learning at the beginning
Repeated attempts to retrieve [testing effect/generation effect] builds up resistance
What can lead to memory distortions?
Incomplete or inaccurate retrieval - but not all memories are equally vulnerable to forgetting at all points in their history.
What is Jost’s Law?
Equal, older memories are more durable, forgotten less rapidly. New memories are initially vulnerable until they are consolidated.
What is consolidation?
The process that transforms new memories from a fragile state, in which they can be disrupted, to a more permanent state.
What are the two types of consolidation?
Synaptic consolidation and Systems consolidation
What is synaptic consolidation?
These are structural changes in synaptic connections between neurons [hours/days to complete]. Memories are vulnerable until these changes are made
What is systems consolidation?
This is the gradual shift of memory from hippocampus to the cortex. Memory components [in cortex] are replayed until they are linked [months/years to complete] - memories are vulnerable for as long as they rely on the hippocampus
What are the causes of incidental forgetting?
Trace decay, context shifts, and interference
What is trace decay?
Memories weaken due to passage of time. Priming and familiarity especially prone to decay. ACTIVATIONS FADE, but memory stays intact.
What is the biological basis for trace decay?
Synaptic connections degrade and neurons die as time goes by [memories do the same]. Neurogenesis [growth of new neurons] means that the structure is remodelled and connections modified.
Good for new learning - generation of new associations
Bad for older memories retained in hippocampus.
Behaviourally, it is difficult to prove trace decay, which two factors cannot be controlled when attributing forgetting to trace decay?
Rehearsal and Interference from new experiences
Why are context shifts a cause of incidental forgetting?
Different cues are available now than the ones available at encoding. Similarity between encoding and retrieval context may explain forgetting.
What are the two types of interference?
Retroactive and Proactive
What is interference?
Similar memories hinder retrieval, and it is difficult to discriminate between them. It occurs due to the negative effect of having competitors, it increases with the number of competitors a target memory has.
What is competition assumption?
Memories associated to a shared cue automatically impede retrieval when the cue is presented.
How many associators does a cue activate?
All of them
What do the activated associates compete for?
Access to consciousness
What hinders access to a target memory?
Competitors
What is retroactive interference?
Introducing a new memory impairs recall of a first memory.
What is proactive interference?
The tendency of older memories to interfere with retrieval of recent experiences and knowledge.
What is part-set cuing impairment?
Recall is impaired by the provision of retrieval cues drawn from the same category of items in memory. [Providing hints may impede memory retrieval]
What is retrieval-induced forgetting? Proposed by Anderson et al., 1984
Selective/partial retrieval can harm recall of other memories related to the retrieved item. Selective retrieval may contribute to more severe forgetting for information that is not practiced/retrieved.
What are the two interference mechanisms?
Associative blocking and associative unlearning.
What is associative blocking?
A cue fails to elicit a target trace because it repeatedly elicits a stronger competitor, leading people to abandon efforts to retrieve target, e.g., tip of the tongue
What is associative unlearning?
Associative bond linking a stimulus to a memory trace is punished by weakening it after being retrieved in error.
What is inhibition?
Allows an unwanted response to be stopped, while an alternative response needs to get strengthened.
What is the functional account of forgetting?
Forgetting is to control retrieval in the face of competition. May serve a functional purpose and therefore can be an ACTIVE PROCESS
According to the functional account of forgetting, how can it be beneficial?
Facilitates future retrieval attempts of practiced/strengthened memories by inhibiting competitors - serves goal-directed behaviour and decision making.
How should memory NOT be viewed?
As a means for high-fidelity transmission of information
What is the goal of memory?
To guide intelligent decision making
Another perspective of memory is that it promotes flexibility and generalisation, it shows that forgetting is not a failure of memory, but what does it represent?
An investment in a more optimal mnemonic strategy.
