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Memory
Memory
A Memory Experiment• Shortly, you will be shown a series of items.
• Watch carefully, as you will be asked to recall as many of them as you can at the end of the presentation.
• You can write which items you remember on a piece of paper, but should not write anything as you go along.
• When you come to recall the items, you can write them down in any order that you want.
• Remember to watch carefully!
• When you are ready, the presentation will begin…
End of
Presentation
• What can you
• remember?
• People tend to remember the first few items in a list.
• This is known as the primacy effect.
• People tend to remember the last few items in a list.
• This is known as the recency effect.
• People tend not to remember the items that occur in the middle of a list.
• These findings are also described as the serial position effect. In other words, the serial position of an item in a list (e.g. whether its 1st, 2nd, 3rd, last, etc) affects the chance of it being remembered.
A graph to demonstrate the serial position effect
0
5
10
15
20
25
serial position of items
% r
ecal
l
primacy effect recency effect
Question: Why does the primacy effect happen?
Answer: Because the first few items are ________ and _______ to ____ _____ memory. This means they are _______ for recall at the end of the presentation.
Question: Why does the primacy effect happen?
Answer: Because the first few items are rehearsed and transfer to long term memory. This means they are available for recall at the end of the presentation.
Question: Why does the recency effect happen?
Answer: Because the last few items are still in _____ ____ memory and have not yet _______. This is why people often to remember them first, otherwise they will be lost.
Question: Why does the recency effect happen?
Answer: Because the last few items are still in short term memory and have not yet decayed. This is why people often to remember them first, otherwise they will be lost.
Question: Why are items in the middle of a list often forgotten?Answer:
• Because people are busy rehearsing the first few items they cannot give enough _________ to the middle items.
• Because by the time people reach the end of the list the middle items have _______.
• Because the middle items have also been __________ by the later items that have come into ______ _____ memory.
Question: Why are items in the middle of a list often forgotten?Answer:
• Because people are busy rehearsing the first few items they cannot give enough attention to the middle items.
• Because by the time people reach the end of the list the middle items have decayed.
• Because the middle items have also been displaced by the later items that have come into short term memory.
Question: What would happen if you were shown a series of items but were not allowed to recall them straight away? Instead, you had to count backwards for 30 seconds (a distracter task).Answer:
• You would tend to remember the first few items still because they get rehearsed into long term memory.
• However, the ‘distracter’ task would stop you from recalling items from short term memory. You would ‘lose’ the recency effect.
• The task would probably displace any items left in the STM. Even if it didn’t, all items should have decayed by the end of the task.
Core StudyIn Memory
Terry (2005)
“Serial Position Effects in
Recall of Television
Commercials”
Aim
Terry’s aim was to show that the serial position effect occurs when people are presented with a series of television
commercials.
Hypothesis
• (i) He predicted that if he showed participants a block of television commercials then, on average, the earlier and later ones would recalled more than the middle ones.
• (ii) He also predicted that if he delayed recall of the commercials, only the earlier ones would be recalled well.
Method
• Terry used an experiment, with a repeated measures design. Participants were shown a block of commercials in both conditions.
• In Condition 1, they were asked to recall the products they had seen (in any order they wanted) immediately after presentation.
• In Condition 2, they were asked to recall the products they had seen (in any order they wanted)after a delay of 3 mins (where they did a written task).
Method
• There were 15 commercials in a block.
• All commercials were 15 or 30 seconds in length.
• Commercials were 10 months old on average.
• Commercials were presented in a different order depending on participant.
Results
Recall
Serial Position of Television Commercial
immediate recall
delayed recall
Results
• As the graph shows, when participants were able to recall the television commercials immediately there was a primacy effect and a recency effect.
• However, when participants’ recall was delayed there was a primacy effect but no recency effect.
Conclusion
The first few commercials were well remembered in both conditions because participants had the time and capacity to rehearse them, and store them in
long term memory.
Conclusion
• The last few commercials were remembered well in the ‘immediate’ condition because they were still held in short-term memory.
• The last few items were remembered poorly in the ‘delayed’ condition because they had been displaced by the distracter task and/or had decayed over the duration of the task.
Evaluation
• The experiment took place in a laboratory using an artificial task…so findings may lack ecological validity.
• The experiment only measured memory through recall of television commercials…so had low construct validity.
• Participants may have deduced the aim of the study…and responded to demand characteristics.
