memory is the process in which information is encoded, stored and retrieved
three types of memory
-sensory memory
-short term memory
-long term memory
short term memory
-a temporary store where small amounts of information can be kept for a brief period. can be easily lost
long term memory
-permanent store where limitless amounts of information can be stored for long periods of time
sensory memory
-immediate information coming n from the environment first registers i the sensory store. comes from our senses
capacity
HOW MUCH CAN BE STORED
encoding
HOW IT IS TRANSFERRED FOR STORAGE
duration
HOW LONG MEMORY LASTS
encoding meaning
changing information so that it can be stored
storage meaning
holding information in the memory system
retrieval meaning
-recovering information from storage
capacity meaning
-the amount of information that can be held in a memory store
duration meaning
-the length of time information can be held in memory
short term memory
a limited capacity memory store
long term memory meaning
-a permanent memory store
JACOB(1887) EXPERIMENT ON CAPCITY IN STM
AIM: research our capacity in STM
PROCEDURE: participants were n with strings of letter or digits and were asked to repeat them back in the same order. the length of the string was increased until participant was unable to repeat the sequence accurately. when they fail on 50% of the trials they've reached their digit span capacity
findings of Jacob's experiment on STM
on average, participants recalled nine digits and seven letters. the average recall increased with age. he found mean span for digits was 9.3 and letters was 7.3
conclusions and criticism of Jacob's experiment on STM
STM has a limited storage capacity of between five and nine items but learned memory techniques may increase capacity as people get older
Since there are more letters in the alphabet but only 10 digits letters may be hard to recall
chunking
when you put information together/ grouping information may help to improve memory capacity
jacob's study was done a long time ago before the importance of control in experiments was understood. how might this have affected the results
its not reliable as its not a standardized procedure
miller, jacob and other psychologists have all found similar results in their digit span experiments. what does this tell us about the theory
they're valid and reliable results
however cowan found that we could only remember 4 items. what does this tell us about the theory
depends on what your remembering
does this theory apply to everybody or are there 'individual differences'
depends on you as a person, variation no ones the same
how can you apply the theory to the real world
postcode 6/7 digits as easy to remember
can you devise an experiment to test the capacity of LTM
impossible to test
one word to describe SENSORY MEMORY
large
one word to describe STM
limited
one word to describe LTM
unlimited
the duration for STM
-the duration for which STM can retain info is temporary- a very short time but some findings suggest only a few seconds before it fades unless its rehearsed
peterson peterson (1959) AIM AND PROCEDURE
aim: to see if rehearsal was necessary to hold information in the STM store to test the duration of STM
procedure: participants were given a set of 3 letters to remember but were immediately asked to count backwards in 3's out loud for 3,6,9,12,15,1 seconds. this was done to prevent rehearsal. participants were then asked to recall the letters in the correct order
peterson peterson (1959) FINDINGS AND CONCLUSION
findings: at 3 seconds average recall of the trigrams was about 90% and at 1 seconds average recall had dropped to 3% participants had virtually forgotten all the information after 18 seconds
conclusions: we cannot hold information in thw STM store unless we rehearse it. STM is said to have limited duration: 18-30 seconds
what's meant by displacement
the first piece of information stored in the STM is the first piece to be replaced when maximum capacity happens
What is a criticism of Peterson and Peterson's (1959) study regarding ecological validity?
The study is considered unrealistic as it does not reflect normal everyday tasks like memorizing trigrams.