  Free recall consists of two separate stages: the emptying of working memory
and reactivation [1]. The Tarnow Unchunkable Test (TUT, [2]) uses double
integer items to separate out only the first stage by making it difficult to
reactivate items due to the lack of intra-item relationships. 193 Russian
college students were tested via the internet version of the TUT. The average
number of items remembered in the 3 item test was 2.54 items. In the 4 item
test, the average number of items decreased to 2.38. This, and a number of
other qualitative distribution differences between the 3 and 4 item tests,
indicates that the average capacity limit of working memory has been reached at
3 items. This provides the first direct measurement of the unchunkable capacity
limit of language based items. That the average number of items remembered
decreased as the number of items increased from 3 to 4 indicates that most
subjects were unable to manage their working memories as the number of items
increased just beyond the average capacity. Further evidence for the difficulty
in managing the capacity limit is that 25% of subjects could not remember any
items correctly at least in one of three 4 item tests and that the Pearson
correlation between the 3 item and 4 item subject recalls was a relatively
small 38%. This failure of managing a basic memory resource should have
important consequences for pedagogy including instruction, text book design and
test design. Because working memory scores are important for academic
achievement, it also suggests that an individual can gain academically by
learning how to manage her or his capacity limit.
