Phonetic convergence enhances speech intelligibility

Phonetic convergence describes when a listener's speech becomes subtly more like the speech of a talker they hear. There are many possible reasons why phonetic convergence occurs. Here, we test whether phonetic convergence can facilitate speech perception. A group of adult native-English speaking participants (n = 9) were asked to identify words-in-noise generated from a group of talkers who either: (a) shadowed the speech of the participant (said out loud words they heard - Associated Shadowers) or (b) shadowed the speech of a different participant (Unassociated Shadowers). A separate group of raters (n = 45) performed an AXB similarity-matching task to confirm that Associated Shadowers sounded more like the participant they had shadowed than Unassociated Shadowers. We found that participants more accurately identified the speech of their Associated Shadowers and their accuracy for identifying the speech of their Associated Shadowers was positively related to the rated similarity of their speech. The results support theoretical accounts suggesting that phonetic convergence may facilitate speech understanding between individuals.