Limitations on short-term memory: an example

As an example of the limitations of short-term memory, consider the following demonstration. Please time yourself and take 30-seconds (and only 30-seconds) to memorize as many of the following list of 15 eight-number sequences as you can: 

23984023

23948098

12093507

23339999

76035823

87030345

67009423

79843903

93495877

76098540

70348520

67094803

34095763

34957230

23457266

00004444

 

Now, please minimize your browser and write down as many of the number sequences as possible. Return to your browser when you have finished writing.

 

How did you do? 

Well, with few exceptions, you probably remembered 2 to 4.  Most people remember the sequences 23339999 and 00004444, but not many sequences beyond these two.  One of the sequences might have reminded you of a phone number that you have already committed to long-term memory.  On the rare occasion, someone can recall 10 to 15.  People who can commit the entire list to memory are said to have ‘photographic’ memories, but actually they have developed special techniques or sort-cuts to committee large amounts of information to memory.

Again, do not feel bad if you could only remember a few.  This is a demonstration to point out the human limitations of short-term memory and we are all human (blog author included!).  If you were given more time, you could continue to practice these number sequences and store the complete list in long-term memory.