Structures of memory Flashcards
Outline the multi-store model of memory
The external stimuli/ information from the environment first enter sensory register/ store. If attention is given to the information, then it is passed on to the short-term memory (STM) store.
The capacity of the STM is 7+/-2. Information is usually encoded acoustically at this stage and the duration is between 18-30 seconds.
In order to keep the information in the STM store or move it to long term memory (LTM), it must be rehearsed.
Information in the LTM is usually encoded semantically, the duration is a lifetime and capacity is unlimited.
The process of retrieval (getting information) from LTM involves the information passing back through STM. It is then available for use.
What is the capacity of the short-term memory?
7 +/-2 items
What is the duration of the short-term memory?
18-30 seconds
How is information coded in short term memory?
Mainly acoustically
What is the capacity of long term memory?
Unlimited
What is the duration of long term memory?
Lifetime
How is information coded in long term memory?
Mainly semantically
What was the aim of Murdock’s serial position study?
To investigate whether STM and LTM are separate stores.
Outline Murdock’s method/ procedure
Study design:
1) The study was a laboratory experiment.
2) Participants: male and female students psychology students
3) Participants heard lists of words. The word lists had between 10 and 40 words on them.
4) The participants were asked to recall as many words as they could, in any order (free recall).
5) All procedures were standardised to ensure the experiment could be easily replicated.
What did Murdock find?
The words at the end of the list were recalled best as they were still in the short term memory (recency effect).
The ones at the start of the list were recalled well because they had been transferred to the long term memory (primacy effect).
The words in the middle of the list were not remembered well and this suggests that they were not in either the short or long term store.
What did Murdock conclude?
These results indicate the likelihood of recalling a word depends on its position in a list. Murdock concluded that short term memory and long term memory are separate stores.
What kind of controls did Murdock have in place?
- Familiarity of the words
- The speed at which they were read out
- The education and age of participants
Why did he is a standardised procedure?
To make it easy for other psychologists to replicate (copy) his study and check for reliability.
Murdock used a laboratory experiment to test memory. What is an advantage of using a laboratory experiment to test memory?
In laboratory experiments participants are using their memory under highly controlled conditions e.g., words were all equally familiar and words were all read at the same speed.
This is useful for the researcher who has eliminated many extraneous variables so can be sure the IV has affected the DV if the results show an effect.
What is a weakness of Murdock’s study?
A weakness of Murdock’s laboratory experiment is that he used artificial material to test memory.
Murdock asked participants to memorise random words that had no significance to them (meant nothing to them). In real life people usually have to remember things for a purpose e.g., information for an exam.
This means that his research lacks ecological validity.
