Memory Flashcards
Outline Baddeley’s acoustic and semantic coding study
- Participants given list of acoustically similar words (e.g. cat, cab, can) others given dissimilar words (e.g. pit, few, cow)
- Participants given list of semantically similar words (e.g. great, large, big) others given dissimilar words (e.g. good, huge, hot)
- Immediate recall worse with acoustically similar words, so STM is acoustic
- Recall after 20 minutes worse with semantically similar words, so LTM is semantic
Outline Jacobs’ testing digit span capacity study
- Researcher reads four digits and increases until the participant can’t recall the order correctly
- Final number = digit span
- On average, participants could repeat back 9.3 numbers and 7.3 letters in the correct order immediately after they were presented
Outline Miller’s magic number 7 +/- 2 capacity study
- Miller noted that everyday things come in 7s (e.g. 7 days of the week / 7 deadly sins, etc.)
- Span of STM is about 7 items (plus or minus 2) but is increased by CHUNKING - grouping sets of digits into meaningful units
Outline Peterson and Peterson’s duration of STM study (consonant syllables)
- 24 students given consonant syllable (e.g. YCG) to recall and a 3 digit number to count backwards from to avoid rehearsal
- After 3 seconds, average recall was 80%, after 18 seconds, iy was about 3%
- STM duration = up to 18 seconds
Outline Bahrick’s LTM duration study (yearbook photos)
- 392 Americans aged 17 - 74
- Recognition test - 50 photos from high school yearbooks
- Free recall test - participants listed names of their graduating class
- Recognition test - 90% accuracy after 15 years, 70% after 48 years
- Free recall test - 60% accuracy after 15 years, 30% after 48 years
- LTM duration = up to a lifetime
Baddeley identified two memory stores. How is this a strength of coding of memory?
- Later research showed there are exceptions to Baddeley’s findings
- STM is mostly acoustic and LTM is mostly semantic
- This led to the development of the MULTI-STORE MODEL
Baddeley used artificial stimuli for his study. How is this a weakness?
- Words had no personal meaning to participants, so tells us little about coding for everyday memory tasks
- When processing more meaningful information, people use SEMANTIC coding, even for STM
- This suggests that the findings from Baddeley’s study have limited application
Jacobs’ study has been replicated. How is this a strength of STM capacity?
- Study may have lacked adequate controls (confounding variables, e.g. participants being distracted) due to the study being old
- HOWEVER, Jacobs’ findings have been confirmed in later studies (Bopp and Verhaegen)
- This shows that Jacobs’ study is a valid measure of STM digit span
Miller may have overestimated STM capacity. How is this a weakness?
- Cowan reviewed other research and concluded that the capacity for STM was only about 4 (plus or minus 1) chunks
- This suggests that the lower end of Miller’s estimate (5 items) is more appropriate than 7 items
Peterson and Peterson used meaningless stimuli. How is this a weakness of duration of STM?
- Recall of consonant syllables does not reflect meaningful everyday memory tasks
- Therefore, the study lacked EXTERNAL VALIDITY
Bahrick’s study has high external validity. How is this a strength of duration of LTM?
- Everyday meaningful memories (names and faces) were studied
- Shepard found that when lab studies were done with meaningless pictures to be remembered, recall rates were lower
- This means that Bahrick’s findings reflect a more “real” estimate of LTM duration
Sketch the multi-store model of memory
Outline the sensory register from the multi-store model
- All environmental stimuli pass into the sensory register. This part of memory has 5 stores for each of the senses
- CODING - depends on the sense (visual in iconic, acoustic in echoic, etc.)
- DURATION - very brief, less than half a second
- CAPACITY - very high, e.g. over 100 million cells in one eye, each storing data
Outline the transfer from sensory register to STM in the multi-store model
Information passes further into memory only if attention is paid to it (ATTENTION is the key process)
Outline short term memory in the multi-store model
- Limited capacity store of temporary duration
- Coding = acoustic
- Duration = about 18 seconds unless information is rehearsed
- Capacity = between 5 and 9 (7+/-2) items before some forgetting occurs
Outline the transfer from STM to LTM in the multi-store model
- Maintenance rehearsal occurs when we rehearse material
- We can keep information in STM as long as we rehearse it
- If we rehearse it long enough, it passes into LTM
Outline long term memory in the multi-store model
- Permanent memory store
- Coding = semantic
- Duration = up to a lifetime
- Capacity = potentially unlimited
Outline retrieval from LTM in the multi-store model
When we want to recall information stored in LTM, it has to be transferred back to STM by a process called RETRIEVAL
There is evidence from Baddeley showing STM and LTM are different. How is this a strength of the multi-store model?
- Baddeley found that we tend to mix up words that sound similar when using our STMs (so STM coding is acoustic)
- But we mix up words that have similar meanings when we use our LTMs (which shows LTM coding is semantic)
- This supports the multi-store model’s view that these two memory stores are separate and independent
Jacobs and Peterson and Peterson’s studies show that the multi-store model may not be a valid model of how memory works in everyday life. How is this a weakness?
- The studies tend not to use everyday information (e.g. faces or names)
- They use digits/letters (Jacobs) or meaningless consonant syllables (Peterson and Peterson)
- Therefore, the multi-store model may not be a valid model of how memory works in everyday life where memory tends to involve meaningful information
Shallice and Warrington found there may be more than one STM store. How is this a weakness of the multi-store model?
- Shallice and Warrington - KF had amnesia. STM recall for digits was poor when he heard them, but was much better when he read them
- Other studies confirm there may also be a separate STM store for non-verbal sounds (e.g. noises)
- Therefore, the MSM is wrong to claim there is just 1 STM store, processing different types of information
According to Craik and Watkins, prolonged rehearsal is not needed for STM → LTM transfer. How is this a weakness of the multi-store model?
- Craik and Watkins argue there are 2 types of rehearsal called maintenance and elaborative rehearsal
- MAINTENANCE (amount of rehearsal) is the one described in the multi-store model
- ELABORATIVE is needed for long term storage. This occurs when you link information to your existing knowledge, or think about its meaning
- This suggests the MSM doesn’t fully explain how long-term storage is achieved
The multi-store model is a bygone model. How is this a weakness?
- The MSM was useful at explaining a lot of evidence at the time (e.g. differences between STM and LTM)
- HOWEVER, it’s become clear that the MSM can’t account for many research findings (e.g. amnesia) and oversimplifies the nature of STM, LTM and rehearsal
- Therefore, the MSM was a good starting point for developing more valid models of memory that explain the research evidence better
Outline episodic memory
- Stores events from our lives
- Likened to a diary of daily personal experiences
- Time stamped - you remember when things happened
- Conscious effort to be recalled