slide 1 chapter 8 memory. slide 2chapter 8 – memory what is memory? often when we use the word...

Chapter 8

Memory

Chapter 8 – Memory Slide 2

What is Memory?

Often when we use the word “memory” we are referringto the conscious recollection of some past experience.

e.g., What did you wear yesterday?

However, in Psychology, we define memory much moregenerally. My definitions would go something like:

Memory influences are any influence by which pastexperiences affect current performance.

Given this more broad definition, there may be a large number of ways in which memory can influence us …for example:


Alphabetic Arithmetic Example

• A+3=D • C+2=F• T+2=W• A+3=D• S+3=V• C+2=F• S+3=V• T+2=W

• C+2=F• S+3=V• A+3=D• T+2=W• A+3=D• C+2=F • S+3=V• T+2=W


Rough Processing Model of Memory

Stimulus

Sensory Memory

Working Memory

Long-Term Memory

aka, iconic orechoic memory

aka, short-termmemory

aka, memory


Sensory Memory

Often a “sensory trace” or the stimulus remains after thestimulus is gone.

These traces are termed sensory memory, and they tendto be very short-lived.

Sensory memory was most extensively studies by a cognitive psychologist named Sperling.

Sperling’s studies focused on visual sensory memorywhich he termed iconic memory … here’s how they worked.


Iconic Memory - Full Report Condition

Nine items will briefly be presented in the box below,then they will disappear. How many can you remember?


Nine items will briefly be presented in the box below,then they will disappear. How many can you remember?

K L W

D S P

H J A



What was your subjective impression? Did you think yousaw them all for a short while … then they faded away?



This time, report only the row that is indicated by the arrowthat comes up after the letters are gone.

Iconic Memory - Partial Report Condition


This time, report only the row that is indicated by the arrowthat comes up after the letters are gone.

S J U

B M Q

A R P



If we multiply your number recalled here by 3, we likelyget a larger number than your full report number, right?



Echoic Memory

There is also an auditory version of sensory memory thatis called echoic memory.

You likely have noticed this form of memory in action.For example, the “what? effect”.

As a further example, Steve will now do an auditorydemonstration of echoic memory … his so called “5-3-5-7-2-stop” game.

While iconic memory disappears in approximately 1 second, echoic memory seems to last about 4 seconds.


Stimulus

Sensory Memory

Working Memory

Long-Term Memory



aka, memory



Short-Term or Working Memory

Steve will now read out a set of numbers, try your best toremember them.

That “process” you feel is something Cognitive Psychologistscall working memory.

As Steve will now demonstrate, this form of memory isfairly fragile and capacity limited.

It seems to require a great deal of mental effort to keep things in working memory and, once the leave, they are gone.

Sometimes we use this memory for short-term storage, thoughit also seems necessary for transferring info to long-term mem


The Relation Between Working Memoryand Long-Term Memory

The purpose of Working Memory is not to simply transferinformation into long-term memory.

In fact, some would argue that working memory is what wesometimes call “thinking” and long-term memory clearlyenters into it.

Try some of the following:> D+6=K, true or false?> 5 X 13 = ?> Imagine yourself sitting on a camel, how high could you reach?


Primacy and Recency Effects

If I gave you a long list of words to remember, thenasked you to just recall allthe words you remember,you would likely rememberwords at the beginning andend of the list best. 0

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Recency Effect

The primacy effect is typically attributed to additionalrehearsal of items earlier in the list - Long-term Memory.

In contrast, the recency effect is typically attributed to eithershort-term memory readout or even echoic memory.


How long do things stay in Working Memory?

If a person is allowed to rehearse, information will stay inworking memory for as long as it is rehearsed.

However, if not allowed to rehearse, Peterson & Peterson(1959) showed that information decays from working memoryfairly quickly.

In their experiment, rehearsalwas prevented by making subjects count back from some number by threes while remembering letter trios (e.g., JDK, LPD)

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How are things lost from Working Memory

So, this disappear quite quickly from working memoryif they are not rehearsed … what makes them disappear?

One possibility is that the items just decay over time.

A second possibility is thatnew items coming into working memory actually“push out” things currentlyin it.

This second possibility seemsmost reasonable given the datato the right.

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The Capacity of Working Memory

As we already discussed, working memory has a limitedcapacity. Specifically, the limit seems to be 7 plus orminus 2 chunks.

What is a chunk? Time for another memory experiment!

Hopefully the demo showed that we can greatly increaseour ability to keep things in working memory by chunkingthe information.


Stimulus

Sensory Memory

Working Memory

Long-Term Memory



aka, memory



Long-term Memory

So, a simplistic view on what we’ve said so far is thatthings that are rehearsed enough end up being stored in long-term memory.

Things that are not rehearsed are not.

This transfer of items from working memory to long-term memory is called consolidation, and the theoryof consolidation is primarily supported by concussionstudies (e.g, the football example).

However, this simplistic view is not sufficient.


Depth of Processing - Shallow

• flame

• patch

• sonic

• bless

• fleet

• pears

• spade

• bliss

• forth

• peels

• speed

• block

• freak

• pints

• spice

• blush

• frost

• pluck


DOP - Shallow - Recall


Depth of Processing - Deep

• spoon

• bonds

• glass

• ports

• spray

• boots

• goose

• prize

• steam

• brand

• grass

• quart

• stink

• bride

• green

• queen

• story

• brown


DOP - Deep - Recall


Depth of Processing - Overview

Clearly then, the way that you rehearse informationeffects the likelihood that the information will enterlong-term memory.

Elaborative rehearsal (i.e. deep) tends to produce superiormemory on conceptual tasks like most memory tasks.

Maintenance rehearsal (what we typically do when tryingto remember a phone number for a little while) is not nearly as good at transfering info to long-term memory.

Thus, let us re-visit our “attractive person gives you phonenumber when you do not have paper” example.


Learning Without Rehearsal

As the depth of processing section demonstrates, we canlearn things via elaborative rehearsal … this type ofprocess is sometimes referred to as an effortful process.

However, we often remember things that we did notrehearse in an effortful manner.

The formation of memories for things we did not performeffortful processing on is called automatic processing.

The exact processes underlying automatic transfer to long-term memory are still largely unknown but its very existencechallenges a simple consolidation view.


Improving Your Memory via Mnemonics

Given all these studies of memory, what have welearned about improving memory skills?

Techniques used to improve memory are called mnemonic strategies and, as the name implies, typicalinvolve some form of effortful processing.

We’ll consider three techniques:

(1) the method of loci,(2) the peg-word method,(3) creating a narrative, and(4) creating acronyms


The Method of Loci

In a country far far away (Greece), at a time long longago (sixth century BC), oratory skills were prized, andpaper was rare (OK, it didn’t exist).

Orators had to come up with ways to memorize long speeches. They devised the method of loci.

This method simply involves forming an image of someroute you are familiar with (say the drive to Scarbra),and then “placing” images of the concepts you want to remember along this route. Then, by retracing the routein your head and examining the images, you can reconstructthe concepts in order.


The Peg-Word Method

This method is similar to the method of loci except,instead of putting images along a route, you associatethem (via imagery) with nouns that rhyme with thenumbers.

The typical ones:

one: bun + image representing concept 1two: shoe + image representing concept 2three: tree + image representing concept 3 .32: dirty shoe + image representing concept 32


Other Techniques

Another way of remembering a list of items is tocreate a story (or song) that links the concepts togetherin some ordered manner - this is called forming anarrative.

Yet one more method is to form an acronym thatrepresents the concepts you want to remember:

Roy G. BivThe A.B.C.s of first aid.Begin With Review And Friendor Big Women Really Are Fun!


Memory, One Structure or More?

Currently, one of the debates in memory concerns whetherwe have a single, or multiple long-term memory systems.

Those who believe in multiple memory systems typicallytalk about things like the following:

Episodic Memory - Our memory of very specific eventsin our lives … tends to contain rich detailed info.E.g. - What did you do last night?

Semantic Memory - Our general world knowledge. E.g. - What city is the capitol of Manitoba?

Procedural Memory - Our memory of how to do things.E.g. - How to ride a bike, or kill without thinking.


Implicit vs. Explicit Memory/Tasks

Another distinction that is often made is the distinctionbetween implicit and explicit memory.

Implicit memory tasks are ones that test memory withoutspecifically directing subjects to think about the study items.

In contrast, explicit memory tasks do direct the subject to tryand use study items when completing the memory test.

Implicit and explicit memory are the memory structures these tasks are thought to tap.

An example if you please ...


Implicit/Explicit Example

Graf & Mandler (1984) showed subjects lists of words andask them either to perform “deep processing” (how much doyou like the word) or “shallow processing” (how many lettersdoes the word have) on them

The subjects were then shownstems corresponding to the items(e.g., spice --> spi__) and weregiven either implicit (completewith the first word that comes tomind) or explicit (complete witha study item) instructions. 0

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The Biological Basis of Memory

So how does this all relate to the brain?

Most of what we know about the biological basis of memorycomes from research in two areas:

(1) Neuropsychological studies of human brain- damaged patients.

(2) Psychophysiological studies with animals


Neuropsychological Studies

There are generally two types of memory impairmentsthat can occur as a result of brain damage:

Retrograde amnesia refers to the condition where patientscannot remember events that occurred prior to the headtrauma. Most recent events are the most likely to be lost,and the amount of loss can be from minutes to years.

Anterograde amnesia is a condition wherein patients can remember past events just fine, but they have aninability to form new long-term memories … sometypes at least.


H.M. & Alcoholics

One of the most influential cases of anterograde amnesia wasthe case of H.M., a patient who underwent bi-lateral removalof his hippocampus and amygdala to treat severe epilepsy.

The good news is, his epilepsy was cured. The bad news is,he ended up with a very profound case of anterograde amnesia.

This condition also is a common result of a form of alcoholismtermed Korsokoff’s syndrome. Some alcoholics get all theirnourishment from the liquor, causing vitamin deficiency.A lack of one vitamin in specific leads to profound anterogradeamnesia.


What is lost and what is not?

Patients with anterograde amnesia do have memory forevents that occurred prior to the trauma, so clearly theyhave an intact memory retrieval system.

Thus, it seems their real problem is in storing newmemories … but not allkinds of new memories,just episodic memoriesit seems.

Thus, the hippocampusappears critical for the formation of episodic memories

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Psychophysiological Studies

Critters also appear toform episodic memorieswhich help them to dothings like rememberlocations where they have already searchedfor food.

If their hippocampusis destroyed, they alsoappear to suffer from the loss of episodicmemory.


Summary of Long-Term Memory So Far

So we know that there are a number of ways things canget into long-term memory, and various strategies canbe used to facilitate this process.

We also know that there at least seems to be differenttypes of long-term memory and episodic memory seemsto be the most fragile of these.

Finally, we also know that the hippocampus appears critical for the formation of new long-term episodicmemories, with destruction of the hippocampus leadingto anterograde amnesia.


Remembering

Generally, psychologists believe that the actual processof retrieving information from memory is an automaticprocess.

An automatic process is one that:(a) is carried out very quickly(b) is not under the control of consciousness(c) does not interfere with other ongoing processes

Things are assumed to become automatic via a process ofoverlearning … the assumption being that if some processis performed over and over again, it will become automatic


Reading as an Automatic Process

As an example of an automatic process, remember theStroop experiment we did early in the year?

RED GREEN BLUE REDGREEN RED BLUE GREENBLUE RED GREEN BLUEGREEN BLUE RED BLUE

RED GREEN BLUE REDGREEN RED BLUE GREENBLUE RED GREEN BLUEGREEN BLUE RED BLUE


The Importance of Retrieval Cues

If retrieval from memory is automatic, why does itsometimes seem so effortful to retrieve somethingfrom memory?

For example, the tip of the tongue phenomenon

Retrieval is automatic IF useful retrieval cues arepresent in the environment.

The effortful part of retrieval is trying to come up witheffective retrieval cues that will make retrieval happen.


Tranfer-Appropriate Processing

The most effective retrieval cues are those that, in somemanner, re-create part of the original learning environment.

The importance of recreating the learningenvironment was first shown in what may be the only (so far) psychologyexperiment with SCUBA divers.

That is why when you lose something people will oftensuggest that you “retrace your steps” from some point intime when you had that thing.

It is also related, but not identical, to the concept of state-dependent learning.


Decay from Long-Term Memory

Often students feel like they study hard for an examand, as soon as the exam is complete, the informationthey studied is gone! Is it?

How long does information stay in memory, and howcan we scientifically study memory decay?

This issue was first addressed by Ebbinghaus (1895)and his results and techniques are still interesting.

Ebbinghaus taught himself thirteen nonsense syllables(e.g., dax, wuj) and then tested his memory after variousdelays.


Ebbinghaus’ Results and Real World

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Ebbinghaus’ work suggests we retain some of the infofor at least 30 days, even when it has no meaning.

Similar “real world” studies suggest that we can retaininformation we learned over 40 years ago or more.


Relearning: Gone but not Forgotten

Ebbinghaus also showed that even when information feelslike it has been lost from memory, it is still there.

He demonstrated this using a relearning task in which hehad to relearn a list he had already studied a long time ago.

Even when he felt that the information had been completelylost from memory, it took him less time to relearn that information than it had the first time.

So, even though you think you forget stuff after you writeyour exam, it is still there, and you will be able to get itback quickly if you should ever need to.


Remembering: Part Fact, Part Fiction

When we remember something, some of what we remember is fact, and some is a reconstruction thatfits with our ideas of the world and our current context.

How about an experiment?



How warm was it yesterday?




How cold was it yesterday?




What we seem to do is remember only certain details thatwe experienced, then, while remembering, we create a“story” that includes these details.

The “story” we create is biased by a number of thingsincluding (a) the current context including the questionthat lead to recounting, (b) a desire to tell a coherent,sensical story, (c) our current mental state and beliefs.

Moreover, the confidence we have in our memories seemslargely unrelated to the accuracy of those memories, oftenwe are most confident in the “memories” we created.


A Final Experiment (for now)

SLEEP YARN PINK THREADHAMMER PILLOW MATRESS TIREDCHAIR THIMBLE SHOT BLANKETTETINUS CACTUS SHEET CANDLESTICHES DREAM NIGHT PIERCE


PINK? NEEDLE? ROSE?WATCH?CANDLE? TICKET? BED? BOOK?



SLEEP YARN PINK THREADHAMMER PILLOW MATRESS TIREDCHAIR THIMBLE SHOT BLANKETTETINUS CACTUS SHEET CANDLESTICHES DREAM NIGHT PIERCE

PINK? NEEDLE? ROSE?WATCH?CANDLE? TICKET? BED? BOOK?


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