Factors affecting the incidental formation of novel tone categories

The present research investigated the acquisition of novel tone categories using natural tokens and an incidental learning paradigm. Through three experiments we demonstrated that native English participants, from 18 to 66 years old, can use incidental learning with natural tokens to form four novel tone categories after a short training session with very high, even perfect, accuracy. These findings confirm results from previous studies suggesting that participants can effectively learn novel sound categories via incidental learning. Across the three experiments we used incidental learning to examine factors known to impact novel sound category acquisition. We demonstrated that high variability of tokens within trials resulted in greater learning than variability spread out across trials. Further, training on a single talker resulted in robust learning and but a sharp decline when generalizing to novel talkers. By contrast, training on multiple talkers resulted in less learning, but there no difference when generalizing learning to novel talkers. Further, the presence of an unfamiliar vowel did not impact the incidental formation of novel tone categories. The three experiments illustrated that incidental learning paradigms are an effective and efficient means for learning novel tone categories and for investigating factors known to impact novel sound category acquisition.