Memory span icon

Memory Span

Memory Span is an Alexa Skill that implements the basic memory span task which is used for assessing working memory. The most famous version of this is digit span, where the tester says a sequence of single digits, separated by one second apiece, then waits for the examinee to repeat them back. The sequence increases in length until failure which is the estimate of 'forward digit span'. After that, 'backward digit span' is assessed which is harder as you have to repeat the sequence backwards.

This version of the test allows you to perform tests besides 'digit'. You can ask for 'letter' span or 'color' span as well. Alexa has some problems hearing some letters, so I'm working on that. Studies comparing letter span to digit span have found that letter (and word) span tends to be shorter. (Crannell & Parrish, 1957). You can check if that is true for yourself as well.

Note that the test can be administered in different ways. What I call the 'traditional' protocol is the one used by the Weschler Intelligence tests (WAIS, WISC), where you get two tries at each length before a fail is counted, even if you get the first right. A second or 'stairstep' protocol is described by Woods, et. al 2011. This is the default mode which will move up immediately if you get it right, and moves down if you get two wrong, going up and down until you do 14 trials. This method allows the calculation of a 'mean span' value which is more precise than a single digit span. I suggest using this protocol unless you want to compare to values in the research literature or other tests.

Stimulus sets

As mentioned above, besides digit, this 'skill' can use other stimuli. I have a list of 'first names' that are available in the US, but have not been extended to the English version in UK, Canada, Australia or India, as I'm not sure the list I used would have common names in it. Notes on the different stimuli:

Getting it

If you have an Amazon device like the Echo or a Fire TV, you can try it out by going to the skills store and enabling it.

Feel free to leave comments on the Amazon review page, since Amazon uses them in part to determine popularity. You can also leave it here as a comment. You can also contact me here if you are interested in using this as part of research.

References