Download Memory

Chapter 5 -- Memory
“Memory is the thing you forget with.” -- Alexander Chase
“Forgive your enemies, but never forget their names.” --John F. Kennedy
“Baby, don’t forget my number.”-- Milli Vanilli
Different Types of Memory
 We have different memory systems for different purposes
 Each system has a
 Duration

How long memories last
Capacity
How much information can be stored
Traditional Models of Memory
 Computers and human memory have
(a) an input or encoding stage
(b) a storage process, and
(c) a retrieval process.
Three Memory Stores
 Sensory Memory
 Short-Term Memory
 Long-Term Memory
Sensory Memory
 Properties
 Very short duration (less than 1 second)
 Large capacity
 Lingering activation in perceptual areas of the brain
 Studied using the Sperling technique
 Letters flashed quickly
 Arrow appears next to one row
 Write down letters from that row
 What Sperling Showed
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Full report (first trial)
3-4 correct
Partial report (later trials)
3-4 correct (any row)
SM has a large capacity and short duration
Attention plays a key role in moving information from SM to STM
Short-Term Memory
 Properties
 Short duration (a few seconds – 10 to 20)
 Small capacity (7+2 items)
 Useful for
 Remembering telephone numbers
 Language use
 Getting information to long-term memory
Extending STM
 We use strategies to extend STM
 Increasing capacity
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Chunking
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Rehearsal
 Increasing duration
Chunking: Extending STM Capacity
 Which list of letters is easier to remember?
Chunking: Extending STM Capacity
 By combining items into meaningful “chunks,” we use fewer slots of STM.
The Memory Curve or “curve of forgetting”
Rehearsal: Extending STM Duration
 Silent repetition keeps STM refreshed
 Works until you are interrupted
 Rehearse enough, and STM moves to LTM
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Memory curve
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Primacy effect (LTM)
Recency effect (STM)
Long-Term Memory
 Properties
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(Very) long duration
•
(Very) large capacity
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Hours to decades
Always room for new memories
Types of LTM
Implicit versus Explicit LTM
 Explicit memory
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Conscious awareness; easy to verbalize
Includes semantic and episodic
 Implicit memory
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No conscious awareness; hard to verbalize
Includes skills or habits (how to ride a bike)
Explicit LTM:
Semantic versus Episodic
 Semantic
• Word meanings (a dog is an animal)
• Concepts (dog poo releases methane gas)
• General facts (my dog is named Walter)
 Episodic
• Events that occurred to you (buying a dog)
• Include context (when, where)
Long Term Memory
 Memories may not be retrievable from LTM because they have faded or because of interference by other
memories.
Working Memory (WM): How the Mind Uses STM
 We manipulate the contents of STM
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Problem solving
Planning
 WM includes
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Central executive
Verbal STM
Visuospatial STM
Other STMs
Foundations of Memory
 Genes and memory
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Knockout mice
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Different genes for different memory types
Humans
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Apo E gene related to memory and Alzheimer’s
Making Memories: Encoding
Making Memories: Code
 Memories can be stored in different formats
•
Based on anticipated use
Consolidation
 Consolidation is the strengthening of memories
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Results from frequent or long-term use
New memories are dynamic
Consolidated memories are structural
Craik and Lockhart’s: Levels of Processing
Depth of Processing
 We can process new information in simple (shallow) or complex (deep) ways
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Shallow: based on sensory characteristics
Deep: based on meaning
 Complex processing leads to better memory
Breadth of Processing
 We can encode new information in simple or elaborate ways
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Simple encoding: repeating information
Elaborative encoding: creating connections to existing knowledge
 Elaborative encoding leads to better memory
Memory Phenomena
 Eidetic Memory is more commonly known as photographic memory.
 The tip-of-the-tongue (TOT) phenomenon has been used to study the network of semantic memories
 The study of flashbulb memories has provided information about episodic memory.
 Emotionally charged, episodic memories
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September 11, 2001
Kennedy assassination
Space Shuttle Columbia disaster
Birth of a sibling
Very vivid and accurate
 High level of confidence
 But accuracy does decrease over time
Memory Phenomena
 Encoding specificity has a great deal to do with the ease with which a memory is retrieved.
 If the cues that were present when a memory was encoded or stored are not present during retrieval, it is
difficult to retrieve that memory.
Memory Phenomena
 Encoding specificity appears to be at work in state dependent – or state-trait – learning, which states
that we recall information
The Act of Remembering
 Memory is a constructive process
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Not like a videotape or DVD
Biases and expectations can influence memory
 False memories
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Memories of events that did not occur
Forgetting
 Decay
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Memories fade away over time
 Interference
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Retroactive: new information makes it harder to remember old information
Proactive: old information makes it harder to learn new information
Amnesia
 Retrograde amnesia
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Impairment of memories before onset
Infantile amnesia
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Impairment of memories after onset
Patient H.M.
Movie: Memento
Soap opera plot device
Improving Memory
 Mnemonic devices
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 Anterograde amnesia
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Hierarchical organization
Acronyms/initial-isms
Interactive images
 Spaced practice
Method of loci
 Depth and breadth of processing
Pegword system
Rhyming words