memory - features of STM and LTM Flashcards
outline Baddeley’s research into coding for both STM and LTM.
baddeley investigated how information is stored differently in each memory store. Gave pps in condition 1 acoustically similar words to learn and then asked to immedietly recall and condition 2 acoustically disimilar. Testing (STM). Another group were given semantically similar words/disimilar. After 20 minutes they were asked to recall the words in the correct order (testing LTM)
list 4 features of short term memory
capicity of 7 +/- 2 items (miller)
coding - acoustic (baddeley)
duration - 18 seconds (peterson)
what did Baddeley find in his investigation into coding, what can we conclude.
Found acoustic confusion in the pps that were asked to recall straight away the acoustically similar words. Similarly in the LTM test, pps found it difficult to recall semantically similar words. Baddeley concluded that the LTM memory gets distracted by semantic similarities and muddles them up. However has no issue recalling acoustically similar words because LTM does not pay attention to the way words sound. Therefore can concluded that STM encoded acoustically, LTM encoded Semantically.
what is a limitation of Baddeley’s study into coding
Baddeley’s study lacks mundane realism because it is unrealistic. Learning lists of similar sounding or similarly themed words is not an ordinary activity. As with most memory tests, there was nothing at stake and no reason for participants to try hard to remember.
what is a strength of baddeley’s study into coding
He identified a clear difference between the 2 memory stores, this was a big contribution to our undertstanding of memory and provided the basis for Tulving’s later work into Semantic LTM and Baddeley & Hitch’s theory of working memory.
outline jacobs study into capacity of STM
measured digit span by asking pps to recall 4 digits in the correct order, once completed he would move onto 5 digits, 6 and so on. Until the pps could not remember correctly. Repeated with letters.
what did Jacob find about the capacy of the STM
mean span for digits was 9, for letters it was 7
What was millers contribution to the knowledge of capacity of STM.
stated the span was around 7 items plus or minus 2. he noticed that the number 7 occured regularly in life, for example 7 days in a week, 7 deadly sins ect. in addition he noticed that capicity could be expanded by chucking items together.
what is a historical limitation of jacobs study
Jacob’s study conducted in 1887 is likely to not have adequate control over extraneous variables, such as participant distraction. This is likely to have impacted on their accuracy of recall and ultimately the results drawn as they were unable to perform as well as they may have without distraction. However, the research results have been shown to be reflected in replica research.
outline Peterson’s study into duration STM
tested 24 psychology students in 8 trials each, The students had to recall meaningless three-letter trigrams (for example, THG, XWV) at different intervals (3, 6, 9, 12, 15 or 18 seconds). To prevent rehearsal (practice) the students had to count backwards in threes or fours from a specific number, until they were asked to recall the letters.
what did peterson find about duration of STM?
Peterson & Peterson found that the longer the interval the less accurate the recall. At 3 seconds, around 80% of the trigrams were correctly recalled, whereas at 18 seconds only 3% were correctly recalled.
Peterson & Peterson concluded that short-term memory has a limited duration of approximately 18 seconds
what is an issue with the sample of Petersons study (AO3)
Peterson & Peterson used a sample of 24 psychology students, which is an issue for two reasons. Firstly, the psychology students may have encountered the multi-store model of memory previously and therefore may have demonstrated demand characteristics by changing their behaviour to assist the experimenter. Secondly, the memory of psychology students may be different to that of other people, especially if they had previously studied strategies for memory improvement. As a result we are unable to generalise the results of this study to non-psychology students.
outline Bahrick et als study into duration of long term memory
using 392 American pps, pps were shown a picture of a person from their high-school yearbook, they had to select the name out of a list that matched the photograph of the person.
what did Bahrick et al find about duration of long term memory
90% of the participants were able to correctly match the names and faces, 14 years after graduating and 60% of the participants were able to correctly match the names and faces 47 years after graduation. Bahrick concluded that people could remember certain types of information, such as names and faces for almost a lifetime.
what is a strength of Bahrick’s research into duration of LTM
Bahrick’s study has high levels of ecological validity as the study used real life memories. In this study participants recalled real life information by matching pictures of classmates with their names. Therefore, these results reflect our memory for real-life events and can be applied to everyday human memory.
