Self-generated strategies in the phonological similarity effect

Strategy use is an important source of individual differences during immediate serial reconstruction. However, not all strategies are equally suited for all tasks. Therefore, assessing participants' dynamic strategy selection across contexts is an important next step for reliable interpretation of individual differences in short-term memory span - in both experimental and clinical settings. Strategy use during reconstruction of phonologically similar and phonologically distinct word sets was directly assessed using a self-report questionnaire. In two experiments, participants reported consistent use of phonological strategies across word sets; however, participants reported additionally using non-phonological strategies (i.e., mental imagery and sentence generation) when tasked with remembering phonologically similar words. In particular, strategy selection was most impacted when the phonologically similar word set was either the only word set or the first word set participants received. When the phonologically similar lists were presented after a classic list of phonologically distinct words, participants continued using the phonological strategies that had been effective for the distinct lists. Moreover, in both experiments, accuracy of phonologically similar lists was better predicted by use of non-phonological strategies than use of phonological strategies. Specifically, reported use of verbalization or rehearsal did not predict accuracy, but participants who reported regularly using mental imagery and/or sentence generation (typically in conjunction with rehearsal) displayed greater serial memory for similar words. These results do not undermine the general assumptions of the phonological similarity effect, but they do indicate that its interpretation is less straightforward than previously thought.