Memory Studies

Gave different lists of words to 4 groups of pps to learn:

Group 1-words that sounded similar (e.g.cat, bat, rat)

Group 2-words that sounded different (e.g.pit,cow)

Group 3- words with similar meanings (e.g.big,large,massive)

Group 4-words with dissimilar meanings (e.g.hot,safe,drink)

pps in group 1 only recalled 10% of the words due to acoustic confusion

pps in group 2 recalled 80% of the the words.

information in STM is encoded on an acoustic basis

Gave pps a list of digits and asked them to recall as many as possible.

Found pps could recall an average of 7 items

Magic Number 7 plus or minus 2

STM capacity is limited and ranges from 5-9 items

24 pps had to recall trigrams (e.g.LGK)

Presented pps with a trigram to remember and then told to count backwards from a three digit number given to them

Told to stop counting backwards after a different amount of time: 3, 6, 9, 12, 15 or 18 seconds

After 3 seconds, pps able to recall 80% of the trigrams correctly

After 18 seconds, pps able to recall only 10% of the trigrams correctly

Shows that STM duration is very short and limited to less than 20 seconds if rehearsal is prevented

Gave different lists of words to 4 groups of pps to learn:

Group 1-words that sounded similar (e.g.cat, bat, rat)

Group 2-words that sounded different (e.g.pit,cow)

Group 3- words with similar meanings (e.g.big,large,massive)

Group 4-words with dissimilar meanings (e.g.hot,safe,drink)

To test encoding in LTM, pps given a list of the original words in the wrong order

Task was to arrange them in the correct order, there was a 20 minute delay before they did this and the pps completed a different task

pps in group 3 performed worst with a recall of 55% because of semantic confusion in LTM

Suggests information is encoded on a semantic basis

Estimated number of neural connections in the brain is ! followed by 10.5 km of noughts

Concluded, "no human yet exists who can use all the potential of their brain"

Suggests capacity of LTM is unlimited

Tested memory of 400 patients aged 17-74 years for their former classmates

Asked to identify and name faces of their classmates in their year book

Those who left school in the last 15 years recalled 90% of faces and names

Even those who had left school in the last 48 years recalled 70% of faces and names

Shows that duration of LTM can potentially last a lifetime, especially if the material is processed well and consists of images and feelings rather than just facts