Memory Flashcards
What are the features of Memory stores
Coding
Capacity
Duration
What is the coding for STM
STM are coded acoustically
What is the coding for LTM ?
LTM’s are coded semantically
What is the coding for SR
Visually using images
How did Baddley test for coding ?
- gave different lists of words to four groups of participants and asked them to remember the words.
- the words were shown via a projector.
- they were asked to recall them in the correct order immediately after being shown or 20 minutes after.
What did Baddley find ?
When pps recall the tast immediately they did worse with the acoustically similar words.
When pps delayed the recall task they did worse with the semantically similar words
what is a weakness of Baddleys research
lacked mundane realism: This is because, the task used was artificial and is unusual and not an every-day task that Pps would usually complete. As a result we should be cautious about generalising the findings to different kinds of memory because It may be that when processing more meaningful information, people may use semantic coding even for STM tasks. Therefore, the applicability of Baddeley’s research to society can be questioned and the external validity of his findings.
What is a strength of Baddley’s research ?
well controlled: This is because, the Pps all experienced the same standardised procedures for example seeing each word for 3 seconds which were presented via a projector. This is a strength because it means Baddeley could easily repeat
his research again to see if he achieves consistent results. This suggests that Baddeley’s research
into coding in our LTM and STM has reliable results and as such we can accept them as credible.
what is the capacity of the STM
7 +/- 2
what is the capacity of the LTM
The capacity is unlimited
what is the capacity of the SR
0
what was Jacobs theory of digit span?
He measured the capacity of the STM. He gave Pps a list of digits that they had to recall e.g. 4 digits: 3476.
If they recall these out loud correctly in the correct order, then they can move on to recall 5 digits and so on until they get it wrong.
This determines an individual’s digit span. Jacobs found that the mean span for digits across Pps was 9.3 items. The mean span for letters was 7.3.
what is a weakness of Jacobs capacity digit span research
lacked control over extraneous and confounding variables: This is because in early psychological research such as this study, the experiments often lacked control, which saw Pps become distracted while they were being tested so they
may not have performed as well.
If there is a lack of control, particularly over extraneous and confounding variables, the results could be seen to lack reliability because if they were to replicate the study they may not find the same/consistent results. As a result, the credibility of Jacobs’ research can be drawn into question.
what was Miller’s study regarding Chunking
Miller (1956) noted that things often come in 7s: there are 7 notes on the musical scale, 7 days of the week, 7 deadly sins.
This suggests that the capacity of the STM is an average of 7 items. The rule is 7+/-2 (5-9 items).
However, Miller noted that we can recall 5 words as well as 5 letters – this is because of chunking. We group sets of digits or letters into units
or chunks to make it easier to recall.
Therefore, Capacity can be increased by chunking items together to reduce the number of separate items overall.
what is a weakness of Miller’s Chunking Capacity research
One limitation of Miller’s research is that he may have overestimated the capacity of the STM.
This is because Cowan (2001) reviewed the research and concluded that the capacity of the STM
was only about four chunks of information. This suggests that the lower end of Miller’s estimate (5
items) is more appropriate and realistic than suggesting 7. As a result, the credibility of Miller’s
7+/-2 claims can be questioned.
what is the duration of the STM
18-30 seconds
what is the duration of the LTM
unlimited
what is the duration of the sensory register
fractions of a second
what did Petersen & Peterson find regarding the STM’s duration ?
They tested 24 undergraduate students. Each one took part in 8 trials .
- In each trial the student was given a trigram / consonant syllable.
- They were asked to count backwards in 3’s from a 3 digit number.
- This is known as an interference task and is used to prevent rehearsal of the trigram.
On each trial they were told to stop after a different amount of time 3, 6, 9, 12, 15 or 18 seconds : This is called the retention interval.
They found:
- After 3 seconds = 80% of trigrams were recalled correctly.
- After 6 seconds = 50%.
- After 18 seconds = less than 10%.
Their findings suggest that STM has a short duration of around 18 – 30 seconds.
what did Bahrick find about the duration of the LTM
Bahrick et al (1975) studied 392 Pps from Ohio, America aged between 17-74. High school yearbooks were obtained from either Pps or their old
schools.
Recall was tested in various ways:
1) Photo-recognition test consisting of 50 photos, some from the Pps high school yearbook
2) Free recall test where Pps recalled the names of their graduating class
Pps who were tested within 15 years of graduation were about 90% accurate in photo recognition.
After 48 years, recall declined to about 70% for photo-recognition. Free recall was not as good as photo recognition.
After 15 years this was about 60% accurate, dropping to 30% after 48
years.
This study shows LTM has a very long duration.
what is a weakness of Petersen&Petersons
order effects may have affected the
results:
This is because they used a repeated measures design where all Pps took part in each trial.
This means that we could explain the results due to Pps becoming fatigued meaning accuracy of recall became worse as the trials went on.
This is an issue because it may be that trigrams presented in the first trial caused confusion for later trigrams trials.
Consequently, this affects the internal validity of the experiment as Pp’s may have got muddled and therefore P&P may not have been measuring what they set out to measure, the duration of STM.
what is a strength of Bahrick’s Duration research ?
high external validity: This is because, real- life meaningful memories associated to people you attend high school with were studied rather than artificial stimuli.
This is a strength because it has been shown that when studies on LTM have used meaningless pictures, recall rates were lower.
As a result, we can generalise Bahrick et al.’s research into the duration of the LTM to society.
CP: However, a problem of using real-life research is that confounding variables are not controlled, such as the fact that Bahrick’s Pps may
have looked at their yearbook photos before the research and researched their memory over the years, making us question the credibility of the research.
Who created the Multi store Model of Memory?
Atkinson and Shiffrin
what does the multi store model of memory consist of ?
LTM, STM and the sensory register
