Chapter 7

Human Memory

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Figure 7.1 – Nickerson & Adams (1979) – Which is the correct penny?

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Human Memory: Basic Questions

How does information get into memory? How is information maintained in memory? How is information pulled back out of memory? Memory timeline

– Short term – recent?– Long term – remote?– Operational definitions

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Encoding: Getting Information Into Memory

The role of attention Focusing awareness Selective attention = selection of input

– Filtering: early or late? – F 7.3

Multitasking – issues of driving performance and cell phone use – study by Strayer and Johnson (2001) – F 7.4

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Figure 7.4 Divided attention and driving performance – Strayer & Johnson (2001)

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Levels of Processing: Craik and Lockhart (1972)

Incoming information processed at different levels: Figure 7.5

Deeper processing = longer lasting memory codes Encoding levels:

– Structural = shallow– Phonemic = intermediate– Semantic = deep– Study results – Figure 7.6

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XX 7.5

Table of ContentsFigure 7.6 – Retention at three levels of processing – Craik & Tulving (1975)

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Enriching Encoding: Improving Memory

Elaboration = linking a stimulus to other information at the time of encoding– Thinking of examples

Visual Imagery = creation of visual images to represent words to be remembered– Easier for concrete objects: Dual-

coding theory – Figure 7.7, Paivio et al. (1968) >>>>>>>>>>>

Self-Referent Encoding– Making information personally

meaningful Figure 7.7

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Storage: Maintaining Information in Memory Analogy: information storage in computers ~

information storage in human memory Information-processing theories – Atkinson &

Shiffrin (1977)– Subdivide memory into 3 different stores

• Sensory, Short-term, Long-term

xx 7.8

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Information-Processing Model of Memory

Computer as a model for our memory Three types of memory

– Sensory memory– Short-term memory (STM)– Long-term memory (LTM)

• Can hold vast quantities of information for many years

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Information-Processing Model of Memory

Short-termmemoryStimulus

Sensorymemory

Long-termmemory

Attention Encoding

Retrieval

Forgetting ForgettingForgetting

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Sensory Memory

Stores all the stimuli that register on the senses

Lasts up to three seconds Two types

– Iconic memory• Visual• Usually lasts about 0.3 seconds• Sperling’s tests (1960s)

– Echoic memory (we’ll come back to this)

Sensory

Input

Sensory Memory

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Sensory Memory

We will take a closer look at the Sperling experiment Figure 7.9 summarizes his experiment

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Sperling’s Experiment Presented matrix of letters for 1/20 seconds

– Report as many letters as possible

Subjects recalled only half of the letters Was this because subjects didn’t have enough time

to view entire matrix? – No

How did Sperling know this?

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Sperling’s Iconic Memory Experiment

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Sperling’s Iconic Memory Experiment

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Sperling’s Iconic Memory Experiment

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Sperling’s Iconic Memory Experiment

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Sperling’s Experiment Sounded low, medium or high tone immediately

after matrix disappeared– Tone signaled 1 row to report

– Recall was almost perfect

Memory for images fades after 1/3 seconds or so, making report of entire display hard to do

High

Medium

Low

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xx 7.9

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We are going to try it on the next slide….Are you ready

5

4

3

2

1

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What was the last row…..

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Sensory Memory

Echoic memory– Sensory memory for auditory input that lasts only 2

to 3 seconds

Why do we need sensory memory?

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Short Term Memory (STM)

Limited capacity – magical number 7 plus or minus 2

Limited duration – about 20 seconds without rehearsal– Peterson and Peterson (1959) – F 7.10– Rehearsal – the process of repetitively verbalizing or

thinking about the information

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Memorize the following list of numbers:

1 8 1 2 1 9 4 1 1 7 7 6 1 4 9 2 2 0 0 1

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Write down the numbers in order.

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Now, try again…

1812 1941 1776 1492 2001

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Short-term Memory Limited capacity

– Can hold 7 ± 2 items for about 20 seconds– Maintenance rehearsal

• The use of repetition to keep info in short-term memory

CHUNK– Meaningful unit of information– Without rehearsal, we remember 4 ± 2 chunks– With rehearsal, we remember 7 ± 2 chunks– Ericsson & Chase (1982)

89319443492502157841668506120948888568772731418610546297480129497496592280

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Short-Term Memory as “Working Memory”

STM not limited to phonemic encoding Loss of information not only due to decay Baddeley (2001) – 4 components of working memory

– F 7.11– Phonological rehearsal loop– Visuospatial sketchpad– Executive control system– Episodic buffer

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xxx 7.11

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Long-term Memory

Working orShort-term

Memory

Sensory

Input

Sensory Memory

AttentionLong-term

memory

Retrieval

Once information passes from sensory to short-term memory, it can be encoded into long-term memory

Encoding

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Long-Term Memory: Unlimited Capacity

Penfield’s neural stimulation – p. 284 – data was reinterpreted

Permanent storage?– Flashbulb memories– Brown and Kulick

(1977) – study of assassinations

– Talarico & Rubin (2003) – page 285-286 data in F 7.12 – 9-11 study

– Recall through hypnosis

Debate: are STM and LTM really different?– Phonemic vs.

Semantic encoding– Decay vs.

Interference based forgetting

Figure 7.12

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Long-term memory - Encoding

Elaborative rehearsal– A technique for transferring information into long-term

memory by thinking about it in a deeper way Levels of processing

– Semantic is more effective than visual or acoustic processing

– Craik & Tulving (1975) Self-referent effect

– By viewing new info as relevant to the self, we consider that info more fully and are better able to recall it

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Long-term memory

Procedural (Implicit)– Memories of behaviors, skills, etc.

• Demonstrated through behavior

Declarative (Explicit)– Memories of facts

• Episodic – personal experiences tied to places & time• Semantic – general knowledge

– Semantic network– Figure 7.14

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How is Knowledge Represented and Organized in Memory? Clustering and Conceptual Hierarchies – F 7.13

Schemas and Scripts – Shank & Abelson (1977)

Semantic Networks – Collins & Loftus (1975) – Figure 7.14

Connectionist Networks and PDP Models – McClelland and colleagues - pattern of activity – neuron based model

Table of ContentsFigure 7.14 A semantic network..

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Connectionist Networks and PDP Models

Parallel distributed processing model– Assumes cognitive processes depend on patterns of

activation in highly interconnected networks

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Retrieval: Getting Information Out of Memory

The tip-of-the-tongue phenomenon – a failure in retrieval– Retrieval cues – Brown & McNeil (1966) study – resolve

block 57% of the time with first letter of failed to retrieve word

Recalling an event– Context cues – Godden & Baddeley (1975) – context-

dependent memory study with scuba divers– Bartlett memory research – War of the Ghosts – F 7.15

Reconstructing memories – Loftus studies– Loftus & Palmer (1974) – Figure 7.16 – I: smashed (40.8); collided

(39.3); bumped (38.1); hit (34.0); contacted (31.8) II: smashed (32%) hit (14%) control (12%) (broken glass?)

– Misinformation effect• Source monitoring, reality monitoring • cryptomnesia

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Retrieval

Retrieval– Process that controls flow of information from

long-term to working memory store Explicit memory

– The types of memory elicited through the conscious retrieval of recollections in response to direct questions

Implicit memory– A nonconscious recollection of a prior experience

that is revealed indirectly, by its effects on performance

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Retrieval – Explicit Memory

Free-recall test– A type of explicit memory task in which a person must

reproduce information without the benefit of external cues Recognition task

– A form of explicit memory retrieval in which items are presented to a person who must determine if they were previously encountered

Retrieval failure– Tip-of-the-tongue (Brown & McNeill)

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Forgetting: When Memory Lapses

Ebbinghaus’s Forgetting Curve – F 7.17 Retention – the proportion of material retained –

F 7.18– Recall – Recognition – Relearning

Hill of reminiscence – time frame of remembering

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Seven Sins of Memory – Daniel L. Schacter Transience – loss of

memory over time Absent Mindedness –

breakdown of interface between attention & memory

Blocking – thwarted search for information to retrieve

Bias – influence of current knowledge and belief on how we remember our past

Misattribution – assigning a memory to the wrong source

Suggestibility – memories implanted as a result of leading questions, comments or suggestions when a person is trying to recall a past experience

Persistence – repeated recall of disturbing information or events that one may want to forget

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xxx 7.17

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xxx 7.18

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Why Do We Forget? Ineffective Encoding Decay theory Interference theory

– Type of material– Figure 7.19– Proactive– Retroactive– Figure 7.20

Figure 7.19

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Forgetting

If we remembered everything, we should on most occasions be as ill off as if we remembered nothing.

William James Lack of encoding

– Often, we don’t even encode the features necessary to ‘remember’ an object/event

Decay– Memory traces erode with the passage of time– No longer a valid theory of forgetting– Jenkins & Dallenbach (1924)

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Interference theory

Forgetting is a result of some memories interfering with others– Proactive interference

• Old memories interfere with ability to remember new memories

– Retroactive interference• New memories interfere with ability to

remember old memories– Interference is stronger when material is

similar

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xxx 7.20

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Retrieval Failure

Encoding Specificity Transfer-Appropriate Processing Repression and the memory wards - F 7.21

– Authenticity of repressed memories?– Memory illusions– Controversy

False memories – Roediger & McDermott (1995) procedure – Figure 7.22

Loftus & Pickrell’s (1995) lost-in-the-mall study

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Forgetting

Repression– There are times when we are unable to

remember painful past events– While there is no laboratory evidence

for this, case studies suggest that memories can be repressed for a number of years andrecovered in therapy

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The Physiology of Memory

Biochemistry– Alteration in synaptic transmission

• Hormones modulating neurotransmitter systems• Protein synthesis

Neural circuitry– Localized neural circuits

• Reusable pathways in the brain• Long-term potentiation – changes in postsynaptic neuron

Anatomy– Anterograde and Retrograde Amnesia – F 7.24– case of H.M. – resection in 1953– http://www.npr.org/templates/story/story.php?storyId=7584970– http://www.nytimes.com/2008/12/05/us/05hm.html – Clive Wearing

• Figure 7.23 - Cerebral cortex, Prefrontal Cortex, Hippocampus,• Dentate gyrus, Amygdala, Cerebellum

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xxx 7.23

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xxx 7.24

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Are There Multiple Memory Systems?

Figure 7.25 Implicit vs. Explicit Declarative vs. Procedural Semantic vs. Episodic Prospective vs. Retrospective – Figure 7.26

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xxx 7.25

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Figure 7.26 – Retrospective versus prospective memory

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Improving Everyday Memory Engage in adequate rehearsal – overlearning Testing effect – F 7.27 – Roediger & Karpick

(2006) Serial position effects – F 7.28 Distribute practice and minimize interference -

F 7.29 Emphasize deep processing and transfer-

appropriate processing Organize information Encoding specificity – vary location of studying Use verbal mnemonics – narrative stories –

Figure 7.30 >>>>>>>>>>>>>>>>>>>>> Use visual mnemonics – method of Loci –

Figure 7.31 Akira Haraguchi, 60, needed more than

(10/3/2006) 16 hours to recite pi (π) to 100,000 decimal places, breaking his personal best of 83,431 digits set in 2005.

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Improving Memory

Practice time– Distribute your studying over time

Depth of processing– Spend ‘quality’ time studying

Verbal mnemonics– Use rhyming or acronyms to reduce the amount of

info to be stored

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Improving Memory Method of loci

– Items to be recalled are mentally placed in familiar locations

Interference– Study right before sleeping & review all the material

right before the exam– Allocate an uninterrupted chunk of time to one

course Context reinstatement

– Try to study in the same environment & mood in which you will be taking the exam

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Eyewitness Accounts

Use of Eyewitness in court cases – Cutler & Penrod (1995), Loftus (1993)

What did Jennifer See? Post information distortion Source confusion Hindsight bias Overconfidence

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Your Homework

Read the Chapter Do the quizzes online Make sure you are doing you “Dream Blog”

– 5 dreams with interpretations Work on your “Dream Collage” Chapter 7 Vocab Cards Remember that Chapter 7 Test is on Monday(1st

period) and Tuesday(4th period). If you have questions, please post them on

– ORHS AP Psychology