Memory (psychology)
What is memory and encoding?
Memory is the ability to retaining and recall information after the original object is no longer present
Encoding is when information is converted to code that can be stored in the memory
What are the durations of memory?
Sensory= 0.5 seconds, Short-term= 18-30 seconds, Long-term= unlimited
How do memory stores encode and what are the capacities?
Sesnsory: encodes sense specifically, capacity is very limited
STM: encodes aucoustically, capacity= 7(+/- 2) objects
LTM: encodes semantically, capacity= unlimited
What is the evidence for STM capacity?
Miller & jacobs (1957)
Jacobs recruited 443 college students- North London
Asked them to record letters in the correct order immediately,
Kept adding letters till they could no longer recall,
7 (+/- 2) comfortably, 9< was a struggle
found bits of information can be held in chunks,
but loses accuracy.
What is the evidence for STM duration?
Peterson & Peterson
Brown- Peterson technique
24 male and female psychology students
Used trigrams of syllables, spelt out letter by letter
Immediately gave them 3 numbers to recite backwards to stop the trigrams going to the LTM
participants were given time intervals to stop reciting numbers
3 seconds - 80% trigrams recalled
18 seconds- 10% trigrams recalled
conclusion= STM has a duration 18-30 seconds
What evidence is there for the duration of LTM?
Bahrick
392 american university graduates
shown phootos from yearbook, asked to match names to faces
14 years after graduation, 90% remembered who was who
47 years after graduation, 60% remembered who was who
proves LTM has a duration of atleast 47 years
What evidence is there for ST and LT memory encoding?
Baddeley
Found we tend to mix up words which sound similar in STM
participants were asked to recall similar sounding words immediately (cat, sat, fat)-(recalled less) - shows STM encodes acoustically
participants asked to recall words of similar meaning after 30 mins (big, huge, large)- equally recalled less - shows LTM encodes semantically
What are the 4 stores of the WMM?
Central executive, Phonological loop, Visuo-spatial sketchpad, episodic buffer.
Explain what each store in the WMM does.
CE- monitors incoming data, allocates slave systems to specifc tasks, focuses and divides attention, LIMITED CAPACITY, DOESN'T STORE INFORMATION
PL- slave system- acoustic encoding, auditory info, preserves order in which information arrives, phonological store = words you hear, articulatory process= maintenance rehearsal- repeating sounds on loop to keep them in working memory, CAPACITY= 2 SECONDS
VSS- slave system, stores visual info, limited capacity, visual cache= stores visual data, inner scribe= records arrangement of visual data
EB- slave system, temporary store of info, records events, limited capacity
Who made the MSM and WMM?
MSM- Atkinson & Shiffrin (1968-1971) , WMM- Baddeley & Hitch (1974)