Studied by 1 person
Looks like no one added any tags here yet for you.
what is memory
the mental processes involved in receiving, storing and recovering information
what is the capacity of STM and LTM
+ relevant research
STM - 9-5 items on average = jacobs + miller
LTM- Unlimited - Ramscar
what is the duration of STM and LTM
+ relevant research
STM- 18-30 secs = peterson and peterson
LTM - Up to a lifetime = Bahrick
what is the coding of STM and LTM
+ relevant research
STM - mainly acoustic
LTM - mainly semantic
both baddeley
What are the 3 of memory stores
STM, LTM and the sensory register
What is the sensory register
This store temporarily stores information from our senses - constantly receiving information from around us. Unless we pay attention to it, it disappears quickly - due to spontaneous decay
It has unlimited capacity but a very short duration 50 milliseconds
What was the procedure for Jacobs research into the capacity of STM
participants were given a string of digits for example 4 numbers in a row. The ps have to repeat the list of numbers out loud in the correct order. The list of numbers increases until the p cannot recall them in the correct order.
What were the findings for Jacobs research into the capacity of STM
the mean span of recalled digits was 9.3 items. the mean span for letters was 7.3
What were the conclusions for Jacobs research into the capacity of STM
The capacity of the STM in limited
limited to around 7-9 items
What was the aim for Millers study on the capacity of STM
To investigate the capacity of STM and to see whether chunking assists memory in the short term.
What was the procedure for Millers study on the capacity of STM
Ps were read strings of numbers which they had to recall immediately.
Gradually the length was increased until the ps could only recall the lists correctly on 50% of the trials
Miller also included trials whereby he chunked the numbers into small groups to see if it aided memory
What were the findings for Millers study on the capacity of STM
Miller found that typically people remember 7± 2 items of information e.g letters, numbers or chunks
he also noted that many things come in sevens e.g 7 days of the week, or musical notes in 7s
What were the conclusions for Millers study on the capacity of STM
The capacity of the STM is limited to 7± 2
it is the number of chunks that limit memory, but it does not matter how much goes into each chunk
AO3 + Research into Capacity of STM
millers research has useful real life applications - people use chunking to remember phone numbers
Jacobs research is supported by miller who also found on average people short term memory could remember between 5-9 things. These consistent findings mean the conclusions on the capacity of the STM is reliable
AO3 - Research into Capacity of STM
Millers conclusion that it doesnt matter how much is in each chunk has been criticised. Simon found that it did matter how many items were in the chunk. Ps in his study had a shorter memory span for larger chunks than smaller ones
A problem with the study was that it was carried out in a lab environment. The ps may have concentrated more than they would in everday life. Due to demand characteristics - therefore the results may lack ecological validity. This means the research findings are more difficult to generalise to real life memory settings.
Research on the Capacity of LTM
Capacity of LTM is thought to be unlimited, depending on individual differences. However decay, interference and illness may result in a loss of information. Ramscar (2014) trained computers to mimic elderly people’s brains. he found that as computers aged by aquiring more and more information, they slowed down. The research suggests that human rains slow down because they are filling with information.
What was the aim of Peterson & Peterson research on the duration of STM
To find out how long items would remain in the STM rehearsal
What was the procedure of Peterson & Peterson research on the duration of STM
Presented ps with consonant trigrams e.g CDX
ps were asked to count backwards on 3s from a specified number. - this was to prevent rehearsal
After intervals of 13-18 seconds Ps were asked to stop counting and recall the triagram
What were the findings of Peterson & Peterson research on the duration of STM
Ps were able to recall about 80% if the trigrams correctly after an interval of 3s, but recall became progressively worse as the time intervals increased.
after 18seconds they would recall less than 10% corrrectly.
What were the conclusions of Peterson & Peterson research on the duration of STM
Information disappears/decays very rapidly in the STM when rehearsal is prevented. STM duration is about 18sec
AO3 + Research into Duration of STM
One strength of the research is that it was conducted under highly controlled laboratory conditions. This allowed them to use control procedures such as counterbalancing which reduces order effects. Reduced extraneous variables increases the internal validity of the study
Another strength is that a repeated measures design was used this limits the individual differences in memory performance which allows us to see cause and effect between IV seconds without rehearsal and DV ability to recall trigram.
