Task2 - Long Term Memory And Consolidation Flashcards
Episodic memory
Memory for specific autobiographical events
Semantic memory
Memory for facts or general knowledge about the world and general personal information
Features of episodic memory
- Can be communicated flexibly (declarative)
- Consciously accessible (explicit memory) -> you know that you know
- Tagged with spatial and temporal context
- Autobiographical
- Learned in single exposure -> can be weakened by exposure to similar events
Features of semantic memory
- Declarative
- Explicit memory
- Not necessarily tagged with spatial or temporal context
- Can be personal or general information
- Can be learned in single (interesting/important) or multiple exposure
Nondeclarative memory
Broad class of memory including skill memory that are not always consciously accessible
Implicit memory
Memory that occurs without conscious awareness
Which comes first, episodic or semantic memory?
- View: one need semantic info to form episodic memory (need to know what a birthday is
- View: semantic memory is just info from blurred episodes that only semantic fact remains
- View: e. And s. Memory are interdependent and effect each other
Semantic memory in animals is tested with…
The radial arm maze -> rat learned after a view exposures to run directly to the goal arm
3 principles that govern how successfully a new memory is encoded/ stored
- mere exposure
- Memory is better for info that relates to prior knowledge
- Deeper processing at encoding improves recognition later
Mere exposure
Does not guarantee memory -> we handle money every day but can’t describe images on it
Info related to prior knowledge
When giving title to a story people remember a story better because background information is activated
Deeper processing at encoding
The more deeeply info is analyzed the more likely you successfully encode it
-> levels- of - processing effect (thinking about connections, relationships to other words/ things, semantic content
Why can we retrieve stored memories at some times, yet at other not?
- Transfer- appropriate processing effect (retrieval is better when study and test conditions are similar
- More cues= better recall (free recall, cued, recall, recognition)
- Struggling/ failing to remember can improve memory
Memory failures
- Forgetting
- Interference
- Source monitoring
- False memory
Forgetting
Better at remembering recent events than long ago
Most forgetting occurs in first few hours/ days after learning
Directed forgetting
Procedure in which subjects are first asked to learn info, later asked to remember/ forget specific items -> works
Interference
= reduction in the strength of a memory due to overlap with content of other memories
Proactive interference
Disruption of new learning by previously stored information
Retroactive interference
Disruption of old (previous stored) information by new learning
Source monitoring error
Remembering information but being mistaken about the specific episode that is the source of that memory -> semantic content is preserved, but episodic details are distorted
False Memory
Memory of an event that never actually happened, particular occur when people are prompted to imagine missing details -> later mistakenly think they are true
Association cortex
Many remaining cortical areas are association area -> link information within and across modalities -> formation of basic substrate for semantic information
Anterograde amnesia
Severe loss of the ability to form new episodic and semantic memories , skill and habit learning is still there
Can remember childhood, but not what one did yesterday
Brain parts four semantic memory
Hippocampus is less important -> rely more on other medial temporal lobe structure and temporal lobe
Depends primarily on cortical areas in medial temporal lobes
FMRI study on hippocampal region
Participants view list of words -> incidental encoding -> surprise recognition test
FMRI activity during incidental encoding phase differs for words that are later recognized compared to words that were not
Retrograde amnesia
Loss of memories for events dating from before a brain injury or disruption -> occurs in time graded manner
Robot gradient
A pattern of retrograde memory loss in which recently acquired memories are more prone to disruption than older memories
Standard consolidation theory
Hippocampus and medial temporal lobe structures are required for storage and retrieval of recent episodic memories but not older ones
Components are stored in different areas in the cortex and are linked via hippocampus
Contribution diminishes over time until cortex is capable of retrieving memory without hippocampus
-> explains temporal gradient of retrograde amnesia (links are destroyed)
Multi trace theory
Episodic (and possibly semantic) memories are encoded by an ensemble of hippocampal and cortical neurons
Hippocampus and cortex are normally involved in strong and retrieving even very old memories
Retrieving a memory= new episodic memory
A recalled event can have multiple memory traces
Over time general content of these memories become semantic memory, stored in cortex (independent from cortex
Korsakoff‘s syndrome
Fail to recall many items /events of the past -> patients deny that anything is wrong and try to find lies (confabulation= fill gap in memory with a falsification that they seem to accept as true)
Main cause= lack of Vitamine thiamine (alcoholics)
Brain area episodic and semantic memory
Medial temporal lobe diencephalon
Brain area Nondeclarative learning
Skill learning
Priming
Conditioning (emotional, muscular)
Brain area skill learning
Stratum
Brain area Priming
Neocortex
Brain area Emotional conditioning
Amygdala
Brain area muscular conditioning
Cerebellum
