"An experiment to see the effect of chunking on short-term memory recall".

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Psychology Coursework Introduction

"An experiment to see the effect of chunking on short-term memory recall".

Many psychologists studying memory suggest that there are different stages through which information must travel if it is to be remembered. According to Atkinson and Shiffrin (1968) there are three kinds of memory storage and these vary according to their function and the length of time information is retained. Sensory memory is the first storage. This refers to the initial momentary storage of information, which lasts only a short time. It is recorded by the persons sensory system as a raw non-meaningful stimulus. Short-term memory is the next storage. This can last from around 5 to 15 seconds. The difference between this stage and the sensory stage is that here the information is stored in terms of its meaning rather than as mere sensory stimulation. Repetitive rehearsal would retain the information in short-term memory for longer. The third type of storage is long-term memory. Here information is relatively permanent although it may be difficult to retrieve. Continual rehearsal would be needed here if the information were to be stored for a long time. However, it is said that sometimes the brain does not forget certain things such as a language; even without rehearsal people seem to remember languages for long periods of time. For this coursework I am going to be concentrating on short-term memory, i.e. the effects of chunking on short-term memory recall.

Chunking refers to a process by which information committed to memory is restructured. The term was first used by George Miller in a famous 1956 review paper entitled " The magical number seven, plus or minus two: Some limits on our capacity for processing information. " Miller discussed a memory span experiment conducted by S. Smith. Smith, measured the span of immediate memory for strings of binary digits (e.g. 110010110) and found the span to be about the same as for decimal digits. A few subjects who were taught a higher-level structure that could be applied to the binary digit strings were able to dramatically improve their span, and Smith himself, who mastered the higher-level code, was able to remember strings of 40 binary digits. One higher-level code was based on representing the eight possible 3 digit binary strings as the numerals 0-7 so that 3 binary characters could be recoded and stored as one. For example the code for the string 101 is 5, which takes less storage and can be decoded into 101 when recall is required. This process of recoding the input into a higher-level more compact form is what Miller meant by chunking. Chunking is not reserved for unusual situations like memorizing long strings of ones and zeros, but appears to be widely used. For example a word can be considered a higher-level code (chunk) for the letter sequence of which it is contained.

Miller (1956) claimed that the number of items that can be held in the short-term memory is seven; with the allowance of two either side as not everyone had exactly the same amount of memory. However Miller accounted for the fact that we can get more than nine items into our short-term memory even if it does go through into our long-term memory through rehearsal, by saying that nine items can be nine chunks. Chunking also refers to the structuring of collections of elements during learning and retrieval. For example in remembering a phone number you tend to learn groups of digits rather than a single string of numbers.

Another experiment carried out on chunking was conducted by Herbert Simon (1974). He presented himself with a list of words and found he could not recall them correctly after just one presentation. However he found if he arranged the words into chunks of information the task was considerably easier.

De Groot (1966) also did an experiment on chunking. He found that experienced chess players remembered where 90% of the chess pieces correct places were on the board compared to a much lower amount of non-experienced chess players. De Groot believed that the reason for this was that experienced chess players chunked the board into meaningful units and reproduced the chess pieces by using these units, therefore proving that chunking increases short-term memory.
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In view of the limited capacity and duration of short term memory the phenomenon of chunking appeals to me and after having read various studies of how we can increase short term memory for example Herbert Simon in 1974 when he found that words chunked together to make meaningful chunks of information helped him better remember the data. Another study performed by De Groot in (1966) concluded that chess players could chunk the chess pieces on the board to remember where they were correctly placed after being removed. This shows that chunking can be related to ...

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