Memory

?
  • Created by: jessica
  • Created on: 22-04-14 16:04

The MSM - intro

Atkinson and Shiffrin, 1968

It is used to explain how info flows from one storage to another. It states that there are THREE structures:

  • sensory memory
  • short-term memory
  • long-term memory

These differ in terms of

  • capacity - how much
  • duration - how long
  • encoding - the way its stored
1 of 21

The MSM - STM

STM

All the info that you are currently thinking about.

encoding- the info arrives in its original form. this needs to be encoded. this can be encoded visually or acoustically or semantically (meaning).. so STM tends to be encoded ACOUSTICALLY based on Baddeley's 1966 findings.

capacity - LIMITED. serial digit span studies showed this. long sequences were repeated in order. 50% failed = digit span capacity. JACOBS 1887, he increased the length of his lists until he got to 50% recorded successfully. RESULTS: STM had limited capacity of 5-9 digits.

duration - less than 30 seconds. PETERSON AND PETERSON 1959, trigrams. read aloud. IMMEDIATELY after, they had to count backwards in three's for a specific period of time (RETENTION INTERVAL), which varied from 3 - 18 seconds. this prevented rehearsals of the trigrams. 90% recalled correctly after THREE seconds. but only SIX% after 18 seconds. STM duration is approximately 20-30 seconds.

2 of 21

The MSM - LTM

encoding - SEMANTIC. Baddeley - read a list of words, retention interval for 20 mins - semanatic list was the worst - LTM tends to be encoded semanatically.

capacity - UNLIMITED.

duration - LIFETIME. you do not need to rehearse info once it is in the long term memory store. BAHRICK, 1975. 400 ppts asked to recall names of classmates from high school. (free recall). also shown a picture and list of names, some ex-school friends. they had to identify friends (recognition). within 15 years, 90% could recalll. 48 years, 80% recalled names. suggests memory lasts A LONG TIME.

3 of 21

The MSM - LTM

encoding - SEMANTIC. Baddeley - read a list of words, retention interval for 20 mins - semanatic list was the worst - LTM tends to be encoded semanatically.

capacity - UNLIMITED.

duration - LIFETIME. you do not need to rehearse info once it is in the long term memory store. BAHRICK, 1975. 400 ppts asked to recall names of classmates from high school. (free recall). also shown a picture and list of names, some ex-school friends. they had to identify friends (recognition). within 15 years, 90% could recalll. 48 years, 80% recalled names. suggests memory lasts A LONG TIME.

4 of 21

THE MSM - the graph

(http://www.mindoutlined.com/images/zmemorystmltmcompare.gif)

5 of 21

The MSM - the model

(http://www.psychteacher.co.uk/memory/multistore-model_files/slide1.jpg)

6 of 21

THE MSM - evaluation

POSITIVES

there is alot of evidence for the STM/LTM differences.

serial position effect - MURDOCK

  • list of words presented to ppts and had to recall in ANY order
  • the words at beginning and end recalled BETTER then those in the middle.
  • PRIMACY - beginning (rehearsed into LTM) & RECENCY - end (recalled because still in STM).
  • this is evidence of the two seperate memory stores.
7 of 21

The MSM - evaluation

NEGATIVES

  • K.F shows that the STM is not needed for information to go into the LTM. there is another way.
  • OVER SIMPLIFIED.
  • over emphasis on the ONE WAY direction of MSM. MORRIS ET AL, showed there is a two way flow. (the football study, because it MEANT something, it went into the LTM. )
8 of 21

The WMM - intro

Baddeley and Hitch, 1974

this questions the existence of a single STM store.

THE CENTRAL EXECUTIVE - it allocates resources to "slave sytems". limited capacity,processe information from any of the senses.

THE ARTICULATORY CONTROL SYSTEM - verbal rehearsal loop. capicty = 2 seconds

+

THE PHONOLOGICAL STORE - recieves auditory info. stored in acoustic code.

= PHONOLOGICAL LOOP

THE VISUO SPATIAL SKETCHPAD - visual or what things look like info. visual code, things like size,colour and shape. 

9 of 21

The WMM - research

2 tasks at once! (DUAL-TASK) 

it should be easier to do two tasks which use a DIFFERENT processing system, a.k.a verbal and visual rather than two tasks using the same. 

GATHERCOLE AND BADDELEY, 1993

ppts follow a moving spotof light with a pointer. at the same time, 1/2 ppts had to describe angles on a letter F. ----> found this DIFFICULT as they used the visuo-spatial sketchpad for BOTH. 

WHEREAS

the other ppts performed the tracking task along with a verbal task ----> little difficulty DIFFERENT system.

10 of 21

The WMM - evaluation

POSITIVES

- research support from dual task studies. 

- doesn't over-emphasise importance of rehearsal. 

- supported by studies with brain scans. 

NEGATIVES

- it only considers the STM

- there is not much information into the central executive and the capacity has never been measured

11 of 21

EWT - intro

there are MANY factors the affect someones Eye Witness Testimony

  • age
  • race
  • gender
  • individual response to anxiety

also event factors

  • duration of event
  • level of violence witnessed
12 of 21

EWT- anxiety and evaluation

anxiety and stress is almost ALWAYS associated with witnessing a RL crime of violence. 

DEFFENBACHER, 1983 - reviewed 21 studies, he hypothesised the stress performance relationship following the Yerkes Dodson Law. (see below) 

(http://www.sportsmedicineofatlanta.com/graphics/yerkes.gif)

THE POSITIVE EVALUATION

research support - peters and the people going to nurses for injection. week later when asked to identify the nurse and researcher. found it harder to identify nurse due to the rise in stress due to the injection. 

13 of 21

EWT - more evaluation

NEGATIVES

- Yuille & Cutshall contradicts the idea. witnesses gave an accurate EWT after witnessing a shooting DESPITE high levels of stress.

- over simplified explanation - deffenbacher in 2004 said his findings were over-simplistic. he suggested that EWT performance increases up to high levels of anxiety, and THEN at a certain point, there is a DROP

14 of 21

Age of Witness - research

  • Roberts and Lamb, 1999

161 interviews of children who made allegations of abuse. 

They found that in 68 interviews, investigators had distorted childrens reports, BUT 2/3 remained uncorrected by the child. 

  • Cohen and Faulkner, 1989

showed ppts a film of a kidnapping and then presented them with misleading details. findings showed OLDER ppts were more likely than YOUNGER ppts to have been misled by the info. 

15 of 21

Age of Witness - evaluation

ONE POSITIVE

  • research support from cohen and faulkner
  • research support from loftus, 1991. older ppts more susceptible than younger adults remembering a videotaped crime.

NEGATIVES

  • conflicting research - Coxon and Valentine suggests older witnesses might not be so unreliable. compared suggestibility of children and young and old adults. all pptsasked questions after watching videotape of kidnapping. one of the questions they were asked was misleading, and the older ppts were less suggestible. 
16 of 21

Misleading Information - Loftus and Palmer pt. 1

aim

investigating the influence the wording of a question has on ppt's estimates of speed of a car when it was involved in an accident. it assumed that the use of stronger verbs (smashed) would result in HIGHER speed estimates. 

method

45 students. short film clips of the accident were shown. ppts were asked to describe what they had witnessed. 

  • 9 ppts asked "smashed", others asked with verbs "hit, bumped, collided, contacted".
  • the estimated speed WAS affected by the verb.
17 of 21

Misleading Information - Loftus and Palmer pt. 2

results and conclusion

the speed estimates varied depending on the verb. (see the table below)

(http://lornadc.files.wordpress.com/2012/10/l-p-results-74-fw.png?w=474)

evaluation

a follow up study - asked ppts if they had seen broken glass on the road (there was none). 14% questioned with the word 'hit' said yes. 32% who had been questioned with the word "smashed" said there was. other research also supports this study.

NEGATIVE - Yuille and Cutshall (previous card) 

18 of 21

Cognitive Interview

Fisher and Geiselman, 1992

  • change of narrative order - recount scene in different order.
  • change of perspective - recount seen from a different P.O.V
  • reinstatement - return to emotional contet of the scene of the crime
  • report everything - even if its not relevant
19 of 21

Cognitive Interview - evaluation

POSITIVES

  • research support - MORE THAN 50 studies and show its an effective technique. 
  • THE ENHANCED COGNITIVE INTERVIEW (fisher et al, 1989)

16 police inspectors conducted two interviews on 47 witnesses of a mugging. between two interviews, 7 police officers trained using CI. the other 9 formed the control group, found increase in facts in the second interview (the CI technique). 47% more facts. 

  • validity of CI 

NEGATIVES

  • limited use by the police
  • practical problems - Memon et al's study showed no benefits of the CI technique over standard interviewing. 
20 of 21

Strategies for Memory Improvement

CHUNKING

capacity of STM increased if info is grouped into larger "chunks". e.g. 11092001 can be organised into the date of the 9/11 twin terrorist attacks. 

IMAGERY

most important mnemonic. method of loci. imagine a route to college then create images to represent what needs to be remembered. once done, visualise the route and place the images at 'loci' on the route. to recall, recreate the route in your head and visualise the images until remembered.

PEGWORD

visual imagery and rhyme and rhythm and uses numbers. 'one is a bun, two is a shoe'. having learnt the rhymes you need to visualise items to be rememebered. 

21 of 21

Comments

No comments have yet been made

Similar Psychology resources:

See all Psychology resources »See all Memory resources »