Memory

It is sometimes said that “What you are is what you eat” but on the other hand “Who you are is what you remember.”

We can know nothing about ourselves without reference to our memories. Our memories organize our past lives and make sense of them, while at the same time creating a context that influences how we live our future lives and what is important to us. Without our memories we would be hopelessly lost.

Ebbinghaus’s Pioneering Studies of Memory

Hermann Ebbinghaus studied his own ability to memorize new material •  He invented over 2300 nonsense syllables and put them into

random lists. •  Over 6 years he memorized thousands of lists of nonsense

syllables. •  Generally he found that delay between memorization and recall

resulted in the forgetting of a large portion of the material.

Memories, . . . . .

Hermann Ebbinghaus (1850-1909) •  Desired to know how memories are formed •  Assumed memories based on temporal associations formed between

events •  Studied the process of association through serial learning. Approach

similar to behaviorists. •  AàBàCàD •  Invented over 2300 nonsense syllables (bok, gaz, lup, wuc). Why

did he need them? Why not use ordinary words?

Ebbinghaus and Serial Learning

Longer lists take longer to learn N of List N of Readings Time per syllable •  7 1 .4 •  10 13 5.2 •  12 17 6.8 •  16 30 12 •  24 44 17.6 •  36 55 22

Once you learn a list you immediately begin to forget it. •  Measured forgetting by Savings Method:

Number of Times it takes to learn list correctly the first time - Number of Times it takes to relearn list correctly Amount of savings

“How soon we forget” Did Ebbinghaus Underestimate Memory?

•  Interference problem. •  He memorized thousands of nonsense syllable lists over 6 year

period. Learning sets of similar materials makes it harder to learn new material and makes it harder to remember old material

•  Nonsense syllables. •  If he used meaningful materials he would have shown better

learning and retention. Memory related to nature of the information being retained, the level of interest in it, and its significance to that individual.

•  Memorizing in order. •  Ebbinghaus required himself to repeat the syllables in correct order

after memorizing them. We seldom are required to remember things in order.

Is Repetition of an Experience Enough to Create a Memory?

Which is the genuine penny?

A failure to encode

We don’t recognize the penny because it is unlikely that we bothered to “encode” the information.

Memory is divided into three parts •  Encoding

–  The process by which we transform our experience into a form that is memorable

•  Storage –  The means by which we retain memories over time

•  Retrieval –  The process by which we recover our encoded memories from

storage.

Storing Memories Atkinson & Shiffrin Model of Memory

Sensory Memory Store •  The initial storage of sensory information

Sensory Memory

Letters flashed on screen for 1/20 of a second, participants could report about half correctly •  Failure to encode all the letters or failure of memory?

Retest with tone next to line to be remembered •  Memory near perfect

Sensory Memory Store

Iconic Memory •  Memory for visual information •  Very short duration, less than 1 second •  Very large capacity

In moving to the next place for storage for memory, Short Term Memory, attentional processes become very important in determining what we remember.

Storing Memories Atkinson & Shiffrin Model of Memory

Sensory Memory Store •  The initial storage of sensory information

Daniel Levin-Change Blindness

Memory Stores Short Term Memory

•  Medium Duration 20-30 seconds

•  Small Capacity +- 7 items

•  About the size of a telephone number

Short Term Memory Duration

Confusions over what is Short Term •  Short Term Memory is the memory of things in our immediate

awareness •  If attention shifts, items in STM dissipate in approximately 20

seconds (Peterson study) –  Rehearsal can increase the length of time memory retained or

transferred to long term memory –  To maintain items in STM they need to be rehearsed

Demo: You will see 4 letters followed by 3 numbers. Start counting backwards by 3, until I say stop.

vfdh 794

Short Term Memory

Demo: Remember as many letters as you can

XIBMSATMTVPHDX

X IBM SAT MTV PHD X

Short Term Memory

Capacity approximately 7 items plus or minus 2 •  Capacity can be increased by “Chunking” •  Anders Ericsson’s work •  Chess masters and visual “chunks”

Is Short Term Memory composed of only space for temporary storage or does it have other functions?

Processing

Space

Storage

Space

Alan Baddeley (1986),

Short-term memory or

Working memory?

Why do 5 year old children have a STM of about 3 and adults, 7.

Short Term Memory or Working Memory

Short Term Memory might be better termed “Working memory” because space available for remembered items, changes depending on processing needs of the executive.

Demo:

Sing the “Happy Birthday” while drawing what your favorite house would look like.

Sing the “Happy Birthday” while spelling the word ANTIDISESTABLISHMENTARIANISM

---

Overworking Working Memory

Have you noticed that when you attend lectures you know some thing about you remember so much more from them? Why is that?

The importance of a college education is often learning to pay attention to those things which count but it often takes a large store of knowledge to do that.

Book Flower Telephone Carpet Sky Basket Chimney Hammer Tree Coat Picture Shoe Lamp Napkin Carrot

What is responsible for Primacy effect? Recency effect? Children under 8 don’t show primacy effect but do show recency. Why?

The Serial-Position Effect Long Term Memory The location where information is held for hours, days,

weeks, or years. At your 50th high school reunion most of you will be able to recognize 90% of your classmates from the yearbook.

•  No known capacity, decay uncertain

Retrieval

Retrieval from long term memory is different from STM or Sensory memory in which the memory decays rapidly. •  In LTM the memory is stored and brought back to consciousness

by a retrieval cue that was associated with the memory when it was formed

Encoding Specificity Principle •  Association you form at the time of learning material will be most

effective cue in retrieving it.

Memory and Retrieval Cues Cue Target Football Pass Envelope Seal Board game Checkers Inches Feet Social event Ball Geometry Plane Weather Fair Tennis Racket Clergyman Cardinal Stone Rock U.S. Pol Bush Magic Spell

Memory

Cue Football Animal Board game Part of the body Social event Transportation Weather Crime Clergyman Music Shrubbery Write

Encoding Specificity Principle Cue2 Cue1 Target Football Football Pass Animal Envelope Seal Board game Board game Checkers Part of the body Inches Feet Social event Social event Ball Transportation Geometry Plane Weather Weather Fair Crime Tennis Racket Clergyman Clergyman Cardinal Music Stone Rock Shrubbery U.S. Pol Bush Write Magic Spell

State Dependent Memory

Encoding specificity implies memory would be better if your physiological state is the same as what it was during the original learning

Why would you do better on the psych exam if you take it in this room?

The scuba diving experiment •  Participants learned list A while diving and list B while on shore. •  Tested for Lists A & B in both places.

Have you ever gone back to a place from your childhood?

• In therapy, patients remember many sad and unfortunate ways their parents treated them. When they recover they can remember many positive things that happened. Why is that?

Levels of Processing (encoding)

Demo: Half the room close your eyes. Consider each of the items you will be shown as something

you might possibly want for your dorm room and the reason why for your choice.

Close your eyes Count the total number of CAPITAL LETTERS in all of

the words you will be shown. Close your eyes Everyone open your eyes.

eleCtrIc drill sTereo heating pAd poPcorn poppEr teleVision refrigErator teLephone automoBile fryiNg pAn blenDer electric toOth brush RaDio

Encoding Information

How well we remember things depends on the how much we elaborate on the information when we encode it. This is also called the Depth of Processing Model, signifying that information is processed at greater depths (elaborated) it is remembered better.

Depth of Processing

Processing “HEN” Is it written in CAPITAL letters? SHALLOW

SHALLOW (Structural encoding, Physical structure of stimulus) Does it RHYME with PEN? (Phonemic encoding, emphasizes sounds) Would it fit in the following sentence? DEEP "She cooked the ______.“ (Semantic encoding, emphasizes meaning)

Encoding in Visual Images

Further elaborations can occur if we convert what we need to remember into a visual image.

Deeper Processing Through Imagery

"She cooked the _______." or "The great bird swooped down and carried off the struggling _____." "He dropped the WATCH." or "The old man hobbled across the room and picked up his valuable

WATCH that had dropped from his pocket.” The second examples increases the elaborateness of the visual image

for remembering it. The last one is remembered better. Evidence is that encoding without imagery involves the frontal and

temporal lobes of the brain, whereas encoding with imagery involves occipital lobe. Thus more resources devoted to memory, two places rather than one.

Studying for Psychology and Levels of Processing

•  Using Flash Cards to memorize terms. •  Talking about something you read or learned in class

with your friends during lunch •  Repeating the names of items you need to know over

and over again •  Creating a personal meaning for oneself with what you

want to learn •  Taking quizzes until you get all the answers right •  Writing a short summary in your notes about what

your instructor said

Mnemonic Devices

Peg method •  One is a bun •  Two is a shoe •  Three is a tree •  Four is a door •  Five is a hive •  Six is sticks •  Seven is heaven •  Eight is a gate •  Nine is wine •  Ten is a hen

Method of Loci •  Store items in a well-learned geographic place, e.g., street were

you live, or the inside of your house

Try to remember as many as you can

Pinto Siamese Manx Collie Goose Arabian Finch Mustang Swan Warbler Duck Shepherd Dachshund Persian Wren Terrier

Memory and Organization

Our memory for objects is aided if we use the natural organizations that we use for categorizing things.

Proactive and Retroactive Interference

One of the main reasons we forget is interference

Childhood Memories

Is Memory a Tape Recording?

Do our memories make an accurate copy of our experience. •  Brain stimulation - Penfield

Memory as a reconstructive Process •  It would not be possible to have memory for every detail, instead

we remember a few unique details and reconstruct the remainder based on our expectations. However, our expectations can create biased memories.

Eyewitness testimony is susceptible to these effects •  Events occur so quickly that the memory created is susceptible to

disortion. Source memory not very good and becomes poorer with

age –  Can lead to errors in eyewitness accounts of accidents, robberies,

etc., –  Book’s example of the psychologist accused of rape when he actually

was being interviewed on TV at the time.

Semantic Networks Much knowledge is linked by meaning and similarity. Thinking

about some concepts may stimulate others (Spreading activation)

Suggesting False Memories

Experimentally implanting False Memory-Loftus •  Various studies have shown that it is possible by suggestion to

implant memories for events that did not occur. •  About a quarter of subjects in several studies were convinced that

they had been lost as children after a researcher suggested it to them.

•  Plausible events were more likely to be remembered, but the memories were somewhat vague, but these results were achieved after a single, brief suggestion. The “false” or “recovered” memory controversy

•  Reports of long-lost memories, prompted by clinical techniques, are known as recovered memories. Often these are memories of abuse that took place in early childhood. Some true but some not.

–  Are you depressed without a reason, have trouble concentrating, or experience sleepless nights? Then you may be a victim of child abuse.

Amnesia

Retrograde Amnesia •  Time graded – memory loss greatest for memories acquire just

before injury, and least for distant time memories •  Ability to form long-term memories after injury, intact

Anterograde Amnesia •  Short-term memory intact •  Long-term memory intact •  Inability to form long-term memories after injury •  Related to temporal lobe damage and hippocampus

The Case of H. M. Temporal Lobe Amnesia (Hippocampus)

•  In 1953, underwent surgery to stop seizures. Doctors removed parts of Medial temporal lobes, hippocampus and amygdala

•  Suffered some degree of retrograde amnesia for memories 1-3 years before his operation

•  Anterograde Amnesia, STM Normal, LTM Normal, but he could not transfer memories in STM and consolidate them to LTM

•  He can carry on a conversation, he can read, and deal with new information as long as it doesn’t leave awareness

•  He has some awareness of this memory problem: –  “right now, I’m wondering, have I gotten or said anything amiss?

You see, at this moment everything looks clear to me, but what happened just before? That’s what worries me. It’s like waking from a dream. I just don’t remember.”

The Memory Maker

Hippocampus intimately involved in forming new memories •  Aspects of our memories located in different areas, auditory,

visual, etc., •  To remember some part of the brain has to organized this amalgam

of different information into a integrated cohesive memory •  Hippocampus creates the recipe for our newly formed memories

But a little mysterious because once we develop a solid memory, hippocampus no longer needed to remember it.

The tower puzzle. In this puzzle, all the colored disks must be moved to another post, without ever placing a larger disk on a smaller one. Only one disk may be moved at a time, and a disk must always be moved from one post to another (it cannot be held aside).

Surprising learning in Amnesics Mirror Tracing

Organization of LTM Organization of Memory

Studies of brain damaged patients support idea of different types of stored memories

Explicit Memory-Conscious or the intentional act of remembering •  Semantic Memory-Who is the president of the US •  Episodic Memory-What did you eat yesterday for breakfast

Implicit Memory-Remembering without awareness. Past experience shows an influence that can be demonstrated by a change in a person’s actions •  Classical Conditioning Effects--conditioned emotional responses

(e.g., your heart beats faster as you approach your arch rival) •  Procedural Memory—motor skills, habits, tacit rules (e.g., riding a

bike, swinging a tennis racket) •  Priming--implicit activation of concepts in long-term memory

Implicit Memory

Priming •  Enhanced memory for a stimulus, after previous exposure to it

Fill in the blanks with the first thing that comes to mind: _ L _ _ P _ _ N _ _ Z _ _ _ C _ O _ E _ _ R _ _ P_ _ _ P P _ _ A _ H _ U _ These results suggest that the hippocampal structures

damaged are not involved in implicit memory.

Memory for Traumatic Events

Memory for traumatic events •  Repression. Sigmund Freud believed that it was possible to

repress a painful memory, motivation or emotion, to remove it from consciousness so that it couldn’t cause psychic pain.

Contrary to Freud’s assertion it appears that the greater the emotional arousal associated with an event, the greater the likelihood it will be remembered •  Most people do not forget traumatic events if they happen later

than age 3. •  It may appear that people are repressing since people often don’t

want to talk about traumatic events, but they are trying to suppress them, not repress.

Memory for Traumatic Events

Repression of traumatic events does not fit well with our understanding of the biological process of storing memory.

Key player is the amygdala •  There is survival value in remembering things that frighten or

scare us •  During stressful or emotional events, the amygdala encourages the

sympathetic nervous system to boost production of the stress hormones cortisol and adrenaline which lead to better memories.

•  Damage to the amygdala prevents the emotional arousal that creates stronger memories.

Memory and the Brain

Differences between intact hippocampus and amygdala •  Intact hippocampus but damaged amygdala

–  When classically conditioned to fear stimulus like tone and shock, they do not show physiological response to CS although they understand connection

•  Damaged hippocampus but intact amygdala –  No realization that CS signifies shock, but they respond

physiologically.

Frontal-lobe damage •  Damage to the frontal lobes also affects memory because it is

responsible for strategies used in creating memories. •  Frontal lobes help us to focus on what is to be remembered and

helps to inhibit stimulation that might interfere with our remembering.

The Biochemistry of Memory

Hints on how memories are formed at the biological level It is assumed that memories are formed as a result of a

change between the synapses of neurons •  If neuron A excites neuron B, the connection between them

changes, so that it is easier for A to excite B in the future. •  This strengthening called Long Term Potentiation (LTP), and can

last hours or even weeks. •  The hippocampus is an area of the brain where LTP is occurring

more than any other (making memories). •  If this process is interfered with memory formation is disrupted.