Research into memory Flashcards
What was the method for Peterson and Peterson (1959)
Peterson & Peterson (1959)
read nonsense syllables (ZFB) to p’s and got them to count backwards in three’s from a large 3 digit number.
Each participant had 8 trials.
On each trial the time spent
counting backwards was
different (3, 6, 9, 12, 15, 18
seconds).
What was the result for Peterson and Peterson (1959)
80% of nonsense syllables
were recalled correctly after
three seconds
3-5% after 18 seconds
Suggesting that duration has a
capacity of about 18-30
seconds.
What type of experiment did Peterson and Peterson hold?
Lab experiment
What was the aim of Peterson and Petersons experiment (1959)?
Peterson and Peterson aimed to investigate the duration of short-term memory and also provide evidence for the multi-store model.
What was the IV and DV of Peterson and Peterson (1959)
IV: the time interval between hearing the experimenter say the trigram and the participant recalling the trigram
DV: number of trigrams correctly recalled by the participants after every trial.
What was a limitation of Peterson & Peterson’s study
P: A limitation of Peterson & Peterson’s study is that the stimulus material was artificial.
E: Trying to memorise trigrams does not reflect most real-life memory activities where what we are trying to remember is meaningful. So we might say that this study lacked external validity.
C: However, the study is not totally irrelevant as we to try to remember somewhat meaningless data such as phone numbers.
What was the procedure for Bahrick et al (1975)
Bahrick et al (1975) showed 400 p’s aged between 17 and 74 years a set of photos and a list of names- some of which were ex- school friends.
Highschool yearbooks were obtained from the participants or directly from some schools. Recall was tested in various ways:
- Photo recognition test – 50 photos, some from p’s high school year book.
- Free recall test where participants recalled all the names of their graduating class.
What were the results for Bahrick et al (1975)
Participants who were tested within 15 years of graduation were about 90% accurate in photo recognition. After 48 years, recall declined about 70% for photo recognition.
Free recall was not as good as recognition, after 15 years this was about 60% accurate, dropping to 30% after 48 years.
Suggesting that people can remember certain types of info for almost a lifetime, supporting the idea that info is semantically coded.
What type of experiment was Bahricks et al (1975) experiment?
Field experiment
What was the aim for Bahrick et al (1975)
Bahrick investigated people’s ability to recall and recognize names and faces over time.
What was the IV and DV for Bahrick et al (1975)
IV: photo recognition test or free recall test.
DV: correctly recalled/matched names and faces.
What was a strength of Bahricks work?
P: One strength of Bahrick’s study is that it has higher external validity.
E: Real-life meaningful memories were studied. When studies on LTM have been conducted with meaningless pictures to be remembered, recall rates were lower.
C: However, as Bahrick’s research was a field experiment, this meant that there was a lack of control over confounding variables. Such as
participants looking at their yearbook photos and rehearsing their memory over the years.
What was the procedure for Baddeleys (1966) experiment?
Alan Baddeley gave different lists of words to four groups of participants
to remember.
Group 1: (acoustically similar) – words sounded similar
Group 2: (acoustically dissimilar) – words sounded different
Group 3: (semantically similar) – words with similar meanings
Group 4: (semantically dissimilar) – words that all had different meanings.
What were the results for Baddeleys (1966) experiment?
When they had to do this recall task immediately after hearing the words (short-term recall) they tended to do worse with acoustically similar words, suggesting that info is coded acoustically in short term memory.
If participants were asked to recall the word list after a time interval of 20 minutes (long-term recall), they did worse with the semantically similar words, suggesting that info is coded semantically in long-term memory.
What type of experimental design was Baddeleys (1966) experiment?
Lab experiment
What was the aim Baddeleys (1966) experiment?
to investigate whether STM and LTM encode information in different ways
What was the IV and DV of Baddeleys (1966) experiment?
IV: similarity of information and time interval between recall (either immediate or after 20 minutes)
DV: correctly recalled words (in the correct order/position in the list)
What is one limitation of Baddeley’s experiment (acoustically and semantically words)?
P: One limitation of Baddeley’s study was that it used artificial stimuli rather than meaningful material.
E: The word lists has no personal meaning to participants, this means we should be cautious about generalising the findings to different types of memory tasks. For example, when processing meaningful information, people may use semantic coding even for short-term memory tasks.
C: This suggests that the findings from this study have limited application.
Counterargument
Lab experiments have higher control over extraneous and confounding variables.
What was Jacobs procedure (1987)
Jacobs (1987) developed a technique to
measure digit span where the researcher gives a certain amount of digits (4 for example) to a participant, they are then asked to recall these in the correct order out loud.
If this is correct the researcher then reads out more digits and will continue this until the participant cannot recall the order correctly – this determines the individuals digit span.
What were Jacobs (1887) results?
Jacobs found that the mean span for
digits across all participants was 9.3
items. The mean span for letters was 7.3
items.
Supporting Miller’s theory
What type of experiment was Jacobs (1887) study?
Lab experiment
What was the aim of Jacobs (1887) study?
to investigate the capacity of short-term memory for numbers and letters
What was the IV and DV of Jacobs (1887) study?
IV: stimulus type (digits or letters)
DV: span size (length of longest list
accurately recalled) and span total (number of lists accurately recalled).
Theory on capacity: Miller (1956)
Miller (1956) published a famous article entitled ‘The Magical Number Seven, Plus or Minus Two’ in which he reviewed existing research into short-term memory. He said that we can hold seven ‘items’ in short-term memory, plus or minus two. Miller believed that our short-term memory stores ‘chunks’ of information rather than individual numbers or letters.
This can explain why we are able recall items like mobile phone numbers, which contain more than 7 digits. When we try to remember a phone number, which has 11 digits, we chunk the information into groups, for example: 0767…819…45…34, so we only need to remember four chunks of information and not 11 individual digits.
