Words and voices: Episodic traces in spoken word identification and recognition memory.

Most theories of spoken word identification assume that variable speech signals are matched to canonical representations in memory. To achieve this, idiosyncratic voice details are first normalized, allowing direct comparison of the input to the lexicon. This investigation assessed both explicit and implicit memory for spoken words as a function of speakers' voices, delays between study and test, and levels of processing. In 2 experiments, voice attributes of spoken words were clearly retained in memory. Moreover, listeners were sensitive to fine-grained similarity between 1st and 2nd presentations of different-voice words, but only when words were initially encoded at relatively shallow levels of processing. The results suggest that episodic memory traces of spoken words retain the surface details typically considered as noise in perceptual systems.