Cognitive and Meta-cognitive Signatures of Memory Retrieval Performance in Spoken Word Learning

Cognitive models of memory retrieval aim to capture human learning and forgetting over time, and have been applied in learning systems that aid in memorizing information by adapting to the needs of individual learners. The effectiveness of such learning systems critically depends on their ability to use behavioral proxies to estimate the extent to which learners have successfully memorized the materials. The present study examines cognitive and meta-cognitive indicators of memory strength that are present in the learners’ recorded speech signal while studying vocabulary items by vocally responding to cues. We demonstrate that meta-cognitive beliefs about memory performance are reflected in variations in pitch and speaking speed, whereas the objective accuracy of a response is mainly reflected in its loudness. The results of this study contribute to a better understanding of the relationship between prosodic speech variations and (meta)memory processes. Furthermore, they can have important implications for the further development of models of memory retrieval that are used in adaptive learning systems. For example, extracting information about a speaker’s confidence from the speech signal in real time may allow for improvement of predictions of future retrieval success—without the learner having to make explicit confidence judgments after each learning trial.