Domain generality of serial order processing in short-term memory : Evidence from musical and verbal domains.

Recent models of verbal short-term memory (STM) propose a distinction between item storage processes, which are viewed as domain-specific, and order storage processes, which are considered by some authors to be domain-general, at least as regards verbal and visual STM domains. Here we provide further evidence for domain-specific item STM processes and domain-general order STM processes by comparing item and order processing in verbal and musical STM domains. The musical domain is particularly relevant here given its reliance on different kinds of sequential processes (e.g., tones successions, rhythm). Using an interindividual differences approach, we administered to a group of young healthy adults different tasks requiring retention of item identity for words or tones, and tasks requiring retention of serial order information for word sequences or note sequences, as well as a task measuring retention abilities for rhythmic information. For the item STM tasks, we observed strong intercorrelations for within-domain WM measures, but not between-domain WM measures, after controlling for general WM abilities. For the serial order STM tasks, we observed a specific association with the rhythm STM task. These results highlight the importance of temporal sequential processes, as measured by the rhythm STM task, as a driving factor of domain-general STM processes in verbal and musical domains. They furthermore confirm the domain-specificity of item STM processes.