Memory

Encoding, Storage & Retrieval

Memory

Persistence of learning over time via the storage and retrieval of information

3 Processes of Memory

Encoding Processing of information into the memory

system

Storage Retention of encoded information over time

Retrieval Process of getting information out of memory

4 Memory Stores

1. Sensory Memory Immediate, initial recording of sensory

information in the memory system 2 types

Echoic - auditory• 3-4 seconds

Iconic - visual sensory memory• Visual information• 1/4 second

Iconic Sensory Memory

4 Memory Stores

2. Working Memory Processing of briefly

stored information

3. Short Term Activated memory

holds +/- 7 items~30 seconds

4. Long Term Memory Relatively permanent

and limitless storehouse of the memory system

Memory

EncodingStorageRetrieval

Externalevents

Sensorymemory

Short-termmemory

Long-termmemory

Sensory inputAttention to importantor novel information

Encoding

Encoding

Retrieving

Storage Storage Storage

A Simplified Memory Model

Encoding: Automatic v. Effortful

Automatic Processing Quick, unconscious encoding of incidental

informationSpace & time

Well-learned informationWord meanings

We can learn automatic processingReading backwards

Encoding: Automatic v. Effortful

Effortful Processing Slower, requires attention & conscious effort

Rehearsal Conscious repetition of information

Maintain it in consciousness Encode it for storage

Encoding: Automatic v. Effortful

Ebbinghaus rehearsed nonsense syllables TUV ZOF GEK WAV More times practiced on Day 1, the fewer

repetitions to relearn on Day 2

20

15

10

5

08 16 24 32 42 53 64

Time in minutestaken to relearnlist on day 2

Number of repetitions of list on day 1

Ebbinghaus

Encoding

Spacing Effect Distributed practice yields better long term

retention than massed practice

Serial-Position Effect Recall best for info presented first & last

First - more rehearsal timeLast - recency effect

12

Percentage of

words recalled

0

90

80

70

60

50

40

30

20

10

Position of word in list

1 2 3 4 5 6 7 8 9 10 11

Immediate recall

Later recall

Serial Position Effect

What Do We Encode?

Semantic Encoding Encoding of meaning/words

Acoustic Encoding Encoding of sound/words

Visual Encoding Encoding of picture images

Encoding & Retrieval

Type of encoding impacts retrieval Participants recalled word after:

Capital letters? Rhyme with train? Fit in sentence?

Encoding & Retrieval

Encoding & Retrieval

Imagery/Mnemonics Mental pictures Powerful aid to effortful processing Vivid imagery and/or semantic encoding

Encoding & Retrieval

Rehearsal Maintenance Elaborative

Memory drug video

Organization

Chunking enhances memory Items into familiar, manageable units

Occurs automatically1776149218121941ID # (3-2-4)

AcronymsMVEMJSUNP - My very energetic mother just sat

upon nine pins

Storage - Long Term Memory

How does storage work? Lashley (1950) - specific brain cites? - NO!

Rats learn maze - Lesion cortex - Test memoryMemory retained

Gerard (1953) - electrical activity? - NO!Hamsters learn mazeCease brains electrical activation (freeze)Revive and memory retained

Storage - Long Term Memory

‘…memories are more of a spiritual than a physical reality. You try to touch them, and they turn to mist and disappear.’

Storage - Long Term Memory

Synaptic & NT changes Long-term Potentiation

Increase in synapse’s firing potential after S• More NT release & receptor cites (possibly)• Neuron loops or networks

Drugs that block NTs impairs memoryAlcohol impacts serotonin and memory

ECT or concussion impairs memoryBoxer, depressed patient

Storage - Long Term Memory

Flashbulb Memories Strong emotions make for stronger memories Challenger explosion/Princess Diana/JFK Jr.

WHY? Stress hormones boost learning/retention Hippocampus & amygdala structurally close Rehearsal

Long Term Memory Subsystems

Explicit Memory Memory of facts/experiences known Hippocampus- helps move information from

STM to LTMClive Wearing video (Mind 24)

Retrieval

Recall Retrieve learned information not in awareness

Fill in the blank test

Recognition Identify learned information

Multiple choice test

Retrieval Cues

Reminders of forgotten information Guides to where to look for info

Mood/emotion (SDM)Moods are retrieval cuesLearn happy recall best when happy

Context EffectsMemory works better in the context of original

learning

0

10

20

30

40

Water/land

Land/water

Water/water

Different contexts

Same contexts

Land/land

Percentage ofwords recalled

Retrieval Cues

Heard words on land or under water Recall best when context

same for learning & recall

ForgettingEncoding failure

Information never enters the memory system Attention is selective

Cant encode it ALL

Storage Decay Decay of physical memory trace Synapse/NT degradation over time Neural networks atrophy if unused

Retrieval failure (storage problem)

ForgettingSensory memory - the senses momentarily register amazing detail

Short term memory - a few items are both noticed and encoded

Long-term storage - Some itemsare altered or lost

Retrieval from long-term memory - depending on interference, retrieval cuesmoods and motives, some things get retrieved, some don’t Information bits

Memory Construction

Memory does not work like VCR We filter information, fill in missing pieces,

and construct memories during encoding, storage and retrieval

Perceptions of the past

Misinformation Effect Incorporating misleading information into

one's memory of an event

Memory Construction

Eyewitnesses reconstruct memories when questioned

Depiction of actual accident

Leading question:“About how fast were the carsgoing when they smashed intoeach other?” Memory

construction

False Memories

False memories can be created in some people (Loftus) Vivid imagery, journals Repressed memories of abuse No reliable memories pre 3 years of age

Summary: Memory

EncodingStorageRetrieval

Perceptions of the past