Frida Ballard, Sandie Keeerstock, Rajka Smiljanic
Speech produced in a second language (L2) can be less intelligible and more cognitively effortful to process compared to native speech (Van Engen and Peelle, 2014). Here, we investigate whether clear speech, a listener-oriented speaking style aimed at enhancing intelligibility, alleviates some of the perceptual cognitive load and improves listener memory. Sentences produced in clear speech by native speakers are better recognized in noise (Smiljanić and Bradlow, 2011), and better remembered compared to conversationally spoken sentences (Keerstock and Smiljanić 2018, 2019). Clear speech produced by L2 speakers also enhances intelligibility though to a smaller degree (Rogers et al., 2010). In line with the “effortfulness hypothesis” (McCoy et al., 2005), easier-to-understand clear speech may require fewer cognitive resources for speech comprehension and allow more resources to be allocated for memory encoding. What is currently not well understood is the effect of clear speech and foreign accent on listener memory for spoken information.
The present study examines how sentences produced clearly and conversationally by Spanish-accented speakers are remembered by native English listeners. Listeners were first exposed to 30 sentences in clear and conversational speech produced by either a low-accented or high-accented speaker of Spanish. Then, they were asked to identify previously heard sentences from a set of 60 sentences (half presented in the exposure and half new). Discrimination sensitivity (d’) within signal detection theory was used to measure memory performance. The results provide novel insights into whether L2 clear speech enhances the speech signal in a way that reduces cognitive effort and improves listener memory. Future work will also show the contribution of different degrees of foreign-accentedness on memory.
Comments
I really like the design of this poster — very clear and easy to follow. The finding that the L1 Spanish/Portuguese subjects misattributed the speaker’s L1 is super-interesting, and consistent with experiences that I’ve had misidentifying L1 English speakers of L2 French. What do you expect to find when looking at different L1s and L1 Spanish speakers of varying accents? – Rob Reichle
Non-native speakers tend to better understand other non-native speech than native speakers of the language, and are less sensitive to accented speech than native speakers, so I’d expect other L1s and other Spanish speakers may misidentify a low-accented fluent speaker as native. With a more accented Spanish speaker though, NNs may be able to correctly identify the speech as non-native. More accented speech may have more numerous and more salient deviations from the target American English norms, which may be lead to more effort in processing the speech and lower memory scores. For other L1s, assuming intelligibility is still high, it’s possible that some L1 specific characteristics appear in the L2 English CS and actually make it more salient and memorable (such as a trilled R). Other characteristics though, such as French nasal vowels, could actually have the opposite effect and decrease the comprehension and lower memory scores. – Frida Ballard