Coding, Capacity and Duration

What is coding?

Format in which information is stored in the various memory stores.

What is capacity?

The amount of information that can be held in a memory store.

What is duration?

The length of time information can be held in a memory store.

Describe Alan Baddeley’s investigation: (1966 a, 1966b):

• There were no ethical issues

• His aim was to find out if LTM encodes acoustically or semantically.

• He gave different lists of words to 4 groups of participants to remember

• Group 1: Acoustically similar words (eg: cat, cab, can)

• Group 2: Acoustically dissimilar (eg: pit, few cow)

• Group 3: Semantically similar (eg: great, large, big)

• Group 4: Semantically dissimilar (eg: good, huge, hot)

• If the participants struggle to recall word order, it suggests LTM is confused by the similarity, which means this is how the LTM tends to encode.

What did Baddeley’s sample include?

• All participants were men and women from Cambridge University (mainly students)

• All were volunteers, 72 in total, 15-20 in each condition

What was the procedure of Baddeley’s investigation?

• All participants split into 4 groups.

• Each group view a slideshow of 10 words, with all one syllable words.

• Participants get list of words and then carry out an interference task- hearing and writing down 8 numbers 3 times.

• They need to carry out the words from the slideshow in order.

• Words are written around the room, so they just need to concentrate on getting the correct order.

• As you would expect, they go through the trials they get better at remembering the order of the words.

• After the 4th trial, participants get a 15 minute break and perform an unrelated interference task.

• Then asked to recall again, this was a surprise test.

What were the results of Baddeley’s investigation?

• Acoustically similar words appear to be confusing at first but they catch up with the control group.

• The LTM is not confused by acoustic similarities- scores on the last test are similar to the 4th. Suggesting no forgetting has taken place.

• Semantically similar words seem to be confusing, and they lag behind the control group throughout.

What was the conclusion of Baddeley’s investigation?

• He concluded that LTM encodes semantically.

• This is why LTM gets confused when it has to retrieve the order of words which are semantically similar

• It has no problem retrieving acoustically similar words because LTM pays no attention to how the words sound.

• The Interference tasks doesn’t 100% block STM as some information lingers in the rehearsal loop.

• Therefore, LTM gets some help from STM.

What are the limitations of Baddeley’s investigation?

• Uses artificial stimuli rather than meaningful material.

• Therefore, findings can’t be generalised.

• Doesn’t have good ecological validity.