Question

How does acoustic coding in STM(Short Term Memory) account for the difference in memory span between letters that sound the same vs. different

Answer 1

• For example, how do you remember a telephone number you have looked up in the phone book? If you can see it then you are using visual coding, but if you are repeating it to yourself you are using acoustic coding (by sound).

• Evidence suggests that this is the principle coding system in short-term memory (STM) is acoustic coding. When a person is presented with a list of numbers and letters, they will try to hold them in STM by rehearsing them (verbally). Rehearsal is a verbal process regardless of whether the list of items is presented acoustically (someone reads them out), or visually (on a sheet of paper).

• Short term memory can hold a limited amount of information. The results of a typical memory span experiment reveal that a 'typical' short term memory can hold about 6 items (5 to 9 is the normal range).

• The results also suggest that short term memory is verbal in nature; when the items are letters that sound alike (sound alike condition) than when the letters don't sound alike (random letter condition) because when letters sound alike they are confused in memory. Other evidence that short term memory is verbal comes from the fact that memory span is smaller for longer words than for shorter words.

• When you try and remember similar sounding words they become linked with each other which means that you can't remember what words were there, just that they all sounded thus. Because the words are only in STM they haven't been associated with meaning, they are just sounds that your memory is going to be repeating to help it remember.