Memory: Coding, Capacity, Duration Flashcards
What does Capacity refer to?
how much information can be kept in the short-term memory at any time
How did Jacobs research Capacity?
-measured digit span -given number of digits, repeat digits aloud -repeated amount of digits correctly then another digit added -completed until failure
What did Jacobs find from his research into Capacity?
mean number of letters correctly recalled: 7.3
mean number of numbers correctly recalled: 9.3
What did Miller suggest in terms of Capacity?
-observed things come in 7’s +/-2 -noticed people could recall 5 letters as well as 5 numbers
-chunking helps improve capacity
What does Coding refer to?
format in which information is stored
What are the three types of encoding?
1) Visual
2) Acoustic
3) Semantic
Outline how Baddeley conducted research into Coding
-gave different lists of words -group one: acoustically similar -group two: acoustically dissimilar -group three: semantically similar -group four: semantically different
-asked to recall either immediately or 20 minutes after
What were Baddeleys findings in the immediate condition?
worse on acoustically similar words
What were Baddeleys findings in the 20 minute condition?
worse on semantically similar words
What does Duration refer to?
length of time information can be held
How did Peterson and Peterson explore Duration in the STM?
-24 undergraduate students -8 trials -consonant trigrams and 3-digit numbers -remember trigram while counting backwards from 3-digits -recall after 3/6/9/12/15/18 seconds
What were Peterson and Peterson’s findings?
-3 seconds, 80% correct -6 seconds, 50% correct -18 seconds, 10% correct
What did Peterson and Peterson conclude?
limited duration for STM is 18 seconds. highlighted importance of rehearsal.
How did Bahrick explore the Duration of the LTM?
-longitudinal study -followed 392 Americans (17-74) -identify schoolmates from either photo recognition or free recall
What were Bahricks findings into LTM?
Photo Recognition: 90%:15 years 48%:48 years
Free Recall: 60%:15 years 30%:48 years
What did Bahrick conclude for Duration into the LTM?
lasts a lifetime
What did Baddeley conclude from his findings?
STM codes acoustically and LTM codes semantically
What is a main limitation to the research into Coding, Capacity and Duration?
-utilise artificial stimuli -Baddeley worked with word lists -personal meaning may trigger different response -no validity to findings into coding, may use semantic for STM -limited ecological validity
How is Bahricks study a strength as research into duration?
-high external validity -investigated meaningful stimuli -high school year books
-Shepard saw recall rates were lower with meaningless pictures -Bahricks findings reflective of real life duration estimate
What is a strength to Baddeleys research?
-identified clear difference between two memory stores -STM: acoustic LTM: semantic
-important factor in understanding of MSM -difference is consistent in memory system
What is a strength to Jacobs study into capacity?
-replicated -confirmed by Bopp and Verhaegen -improves reliability of results
How is Millers research into capacity limiting?
-may have overestimated STM capacity -Cowan reviewed other research and concluded it is only 4 +/- 1 chunks -suggests lower end of Millers assumption is more appropriate -lacks validity due to opposing research
