Measuring memory span

This study, conducted on a sample of 403 adult subjects, set out to explore the relationships between measures of digit span (forward and reversed), motor and spatial span, and their dependence on a broad range of measures of cognitive function. The results revealed that measures of digit span are closely related, as are measures of motor and spatial span, but these pairs of memory span measures are relatively independent of each other. Furthermore, reverse digit span, motor span, and spatial span appear to rely on what might be regarded as intellectual or executive cognitive functions. As such, the results provide little support for accounts of serial recall, which suggest that order and/or item information are more adequately modelled in a modality-independent form.