Articulatory loop is called the phonological loop due to evidence that it involves speech. We can rehearse about 1.5 seconds of verbal material before it decays. These hold information for use by a central executive. There is evidence that a particular area of the frontal cortex is involved in working memory. How well we have practiced it.
Subjects learn some sentences.
Some sentences are studied twice as long as others. Subjects must discriminate sentences they learned from distractors. They are tested for each sentence more than once, with varying intervening sentences. Both amount of study and how recently the information was accessed affect speed of response. When information becomes easier to access as a result of having been used recently, we say it is more activated.