Features of STM and LTM

Question 1

What is short term memory and long term memory

Answer 1

STM - Memory recalled immediately

LTM - Memory recalled over a long period of time

Question 2

Define encoding, capacity and duration

Answer 2

Encoding - Form information is stored in
Capacity - Amount of info stored
Duration - How long info is stored for

Question 3

Outline the study on the capacity of STM

Answer 3

Jacobs study
443 females repeated strings of numbers/letters
Strings gradually increased

7.3 letters and 9.3 digits on average remembered

STM has a capacity of 5 to 9 pieces of info

Question 4

Evaluate Jacobs study

Answer 4

Controlled environment
Gender bias
Individual differences
Socially sensitive

Question 5

What effect did Miller say chunking had on capacity/evaluate this effect

Answer 5

7 chunks of info can be learnt (increases capacity)

Individual differences
Chunking in different amounts
Socially sensitive

Question 6

Outline Peterson and Peterson’s study on STM duration

Answer 6

Lab experiment with 24 psychology students
3 letter trigrams at different intervals (3,6,9,12,15,18s)
Counted backwards in 3s or 4s to prevent rehearsal

At 3s 80% of trigrams recalled correctly
AT 18S 10% recalled correctly

STM lasts for 18-30 seconds

Question 7

Evaluate Peterson and Petersons study

Answer 7

Lab experiment
Conducted on students
Small sample size
Socially sensitive

Question 8

Outline Bahrichs study on LTM duration

Answer 8

Participants shown highschool photos after graduation
Participants asked to match photos to names

14 years after - 90% matched names with photos
47 years after 60% matched names with photos

LTM capacity is unlimited

Question 9

Evaluate Bahrichs study

Answer 9

High ecological validity - real life memories

Unclear if LTM gets worse with age or if LTM duration decreases

Question 10

Outline Baddeleys study on STM and LTM encoding

Answer 10

Participants asked to recall 5 words in order from each category:

Acoustically similar words
Acoustically dissimilar words
Semantically similar words
Semantically dissimilar words
In STM - recall is immediate
In LTM - Each group is extended to 10 words/ recall tested after 20 minutes

Acoustically similar words were harder to recall for STM
Semantically similar words were harder to recall for LTM

STM encodes acoustically
LTM encodes semantically

Question 11

Evaluate Baddeleys study

Answer 11

Methodological issues - Groups of words are too small

Artificial stimuli

Personal differences