Chunks are the integrated pieces or units of information. Chunking involves the organization of a number of stimuli into various groups. For example, the telephone number 4363591 may be chunked in several ways without altering the order of the numbers.
With temporal chunking, the numbers would be regrouped with pause between the groups, e.g., 436 (pause) 3591.
If the numbers were spatially chunked, the pause would be replaced by a space, e.g., 436 (space) 3591.
The subgroups of numbers may also be demarked by changes in verbal inflection or rhythm, e.g., 4363591, where the numbers 6 and 1 are given more emphasis.
Chunking Facilitates Recall
Chunking a group of nine numbers into three chunks of three numbers each by introducing a pause during a vocal presentation improved recall, decreased transposition errors and made numbers within the sequence as memorable as numbers at the beginning and end of the sequence. Chunking numbers into equal size groups of 3-3-3 leads to better recall than irregular groupings, such as 2-4-3 and 1-7-1 (Ryan, 1969).
In a visual presentation of nine digits, children in grades four and six recalled more digits when the first slide displayed three digits, the second slide displayed the same three digits, plus three more, and the third slide displayed these six digits three more. Recall under this condition was better than that in which the numbers were either ungrouped, or presented spatially as three groups of three each. For children in grade two, recall was better when the numbers were grouped; however, the type of grouping did not affect the nature of the recall (Harris and Burke, 1972).
Usually, chunking involves numbers; however, the procedure may be used to regroup any information. For example, Furukawa (1970) studied the effect of chunking information units in programmed instruction. Groups of information of various sizes were divided by questions.
Chunking provides a method of coping with limitations of short-term memory Opens in new window. Miller (1956) established that the span of immediate memory is 7 + 2 or - 2 chunks of information.
For example, most people, when asked to recall the 12 digit sequence 7 5 1 6 8 3 5 9 2 4 1 7 immediately after they have been given the opportunity to read the number, will usually recall between five and nine of the numbers where each number is a chunk of information.
However, if the numbers are divided spatially or temporally, by the speaker or the listener, into four chunks of three digits each, the number of digits recalled will improve significantly.
A chunk may be defined as a subjectively perceived unit of information. For example, the sequence of eight letters 1 b n y s t w p may be perceived by a young child as eight separate chunks of information regardless of whether the letters are grouped into four chunks of two letters each, or two chunks of four letters each.
Alternatively, an older child or adult presented with a continuous sequence of eight letters, or a sequence of four groups of two letters each, may perceive and rehearse the sequence as two chunks of four letters each.
Regardless of the grouping of the information, the manner in which the observer subjectively chunks and rehearses the items will determine how effectively the information is recalled. On the other hand, a chunked presentation of material is usually better recalled than one that is not chunked.
Hunter (1964) established that the span of immediate memory actually varies with age. At four years of age, children could recall four chunks of information; at seven years of age, five chunks; at ten years, six chunks; at 16 years, seven; and during the mid 50s, six chunks. How many chunks are recalled at each age level is believed to be function of the manner in which an individual attends to the stimuli, the size of the chunks used to organize the material in memory and the active use of rehearsal.
As suggested by George Miller (1956), chunking is a powerful memory tool that greatly increases the amount of information that you can hold in short-term memory.