Memory and encoding

Memory as Information Processing– similar to a computer• write to file• save to disk• read from disk• Encoding– the processing of information into thememory system

Storage and retrieval

• Storage– the retention of encoded information over time• Retrieval– process of getting information out of memory

Memory

Sensory Memory the immediate, initial recording

of sensory information in the memory system

If you can recall information, it must first be stored!

According to Atkinson and Shiffrin’ 3-step model, the first stop is sensory memory or the sensory registers.

Sperling’s experiment

Sperling’s partial report technique illustrates the limitation of sensory memory.

When subjects were told to report ALL 9 letters flashed for a fraction of a second, they could not, but when subjects instructed to report 3 of the letters (one row of 3 letter row display of 9 total letters) they could do so with few errors

This proved that sensory memory could hold the information, but only very briefly

Storage: Sensory Memory

Sensory memory holds information just long enough to recognize and transfer it to STM for further processing

This happens through selective attention Selective attention allows only a small percentage of

sensory messages that bombard us to enter conscious awareness.

It is controlled not only by the focus of our attention but also the expectancies we have prior to exposure

Storage:Sensory Memory

Iconic Memory a momentary sensory memory of

visual stimuli a photographic or picture image

memory lasting no more that a few tenths of a second

Tests of George Sperling Echoic Memory

momentary (3-4 sec) sensory memory of auditory stimuli

Short term and Long term memory

• Short Term Memory/Working Memory

– activated memory that holds a few items briefly– look up a phone number, then quickly dial before the information is forgotten• Long Term Memory– the relatively permanent and limitless storehouse of the memory system

A Simplified Memory Model

Externalevents

Sensorymemory

Short-termmemory

Long-termmemory

Sensory inputAttention to importantor novel information

Encoding

Encoding

Retrieving

Automatic Processing

We process an enormous amount of information effortlessly, such as the following:1.Space: While reading a textbook, you automatically encode the place of a picture on a page.2.Time: We unintentionally note the events that took place during the day.3.Frequency: You effortlessly keep track of things that happen to you.

DEMO DO NOT write down the following list. Listen and read

them, then try to recall them when prompted:CLINTONRUJFETTEXTBOOKNAVBUSHFULFILLGEFMANDATEFET47TAL

Effortful Processing While some information is automatically and

effortlessly processed, some requires focus and attention

Attention is defined as selection certain information for further processing We normally pay attention to only a small portion of

incoming information We pay attention to things according to…

MeaningfulnessDistinctivenessRepetition

Broadbent’s Cocktail Party Phenomenon: we tune out other sounds to focus on what is important

Ebbinghaus and Rehearsal

Effortful learning usually requires rehearsal or conscious repetition

Ebbinghaus studied rehearsal by using nonsense syllables:

TUV YOF GEK XOZThe more times practiced on Day 1, the fewer repetitions to relearn on Day 2Spacing Effectdistributed practice yields better long- term retention than massed practice

Memory:Ebbinghaus’ Contributions

The more the syllables were rehearsed (practiced) on the first day of learning, the fewer rehearsals it took to relearn them on the second.

Encoding: Serial Position 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

Serial Position Effect--tendency to recall best the last items in a list, and then the items at beginning

The Serial Position Effect:Benefits of Rehearsal + Working Memory

When we are given a list of things to remember, we often remember the first items and last items on the list.

This is called the serial position effect.

We are able to rehearse those at the beginning the most and those at the end are still in our working memory! Primacy Effect: tendency to

recall the first items on the list Recency Effect: tendency to

recall the last items on the list

Making Memories Last…

Information quickly learned is information quickly lost!

Spacing Effect: distributed study time yields better long-term retention than massed practice (cramming)!

Testing Effect: more frequent quizzing or previously studied material yields better long-term retention

Bottom line: spread your studying out over time and quiz yourself frequently!

This is sooooo much fun! I

will do it every night

until the test!

Unless evil clowns stop

you!

Chunking

Organizing items into a familiar, manageable unit. Try to remember the numbers below.

1776149218121941

Chunking

If you are well versed with American History, chunk the numbers together and see if you can recall them better.

1776 1492 1812 1941

What Do We Encode?

Semantic Encoding encoding of meaning including meaning of words

Acoustic Encoding encoding of sound especially sound of words

Visual Encoding encoding of picture images

What We Encode:Levels of Processing

Which type of encoding – visual, acoustic or semantic – helps us to remember best?

Craik and Tulving (1975) Subjects forced to encode

words in the three ways Visually (is it capitalized?) Acoustically (does it rhyme

with…) semantically (Would it fit into

the sentence?) Found that semantic encoding

yielded best recall! Spend TIME learning and make

MEANING out of what you wish to recall!

Self-Reference Effect: meaning that is personal – relate information to ourselves.

Bransford and Johnson (1972) had subjects read the following paragraph:

The procedure is actually quite simple.  First you arrange things into different groups depending on their makeup.  Of course, one pile may be sufficient depending on how much there is to do.  If you have to go somewhere else due to lack of facilities that is the next step, otherwise you are pretty well set.  It is important not to overdo any particular endeavor.  That is, it is better to do too few things at once than too many.  In the short run this may not seem important, but complications from doing too many can easily arise.  A mistake can be expensive as well.  The manipulation of the appropriate mechanisms should be self-explanatory, and we need not dwell on it here.  At first the whole procedure will seem complicated.  Soon, however, it will become just another facet of life.  It is difficult to foresee any end to the necessity for this task in the immediate future, but then one never can tell.

Without the context of “doing laundry, subjects could not recall much!

Storage:Short-Term Memory

Short-Term Memory

limited in duration and capacity

“magical” number 7+/-2(Miller, 1956)

0102030405060708090

3 6 9 12 15 18

Time in seconds between presentationof contestants and recall request

(no rehearsal allowed)

Percentagewho recalledconsonants

Storage: Short Term MemoryUnless information in STM is

important/meaningful or is actively rehearsed, it quickly vanishes from STM and is displaced by whatever comes into our minds next

Displacement occurs, then, when new information enters STM and pushes old out

STM storage capacity is limited: the average adult can hold about 5-9 bits or chunks of information in STM

George Miller (1956) Magical Number Seven, plus or minus two

Short Term Memory Capacity

STM (working memory) is what is in your mind RIGHT NOW.

Information in STM only remains there for about 20-30 seconds

STM is very sensitive to interruption and interference

Memory Span

Memory span is a measurement of STM capacity It measures the largest number of items that can be recalled

perfectly from STM after only one presentation No study/rehearsal time is allowed Sometimes used as a component of IQ tests

In STM, acoustic coding seems to dominate – especially for verbal information

Information in STM may be new or retrieved from LTM to be thought about and used.