Foreign Languages Sound Fast: Evidence from Implicit Rate Normalization

Abstract

Anecdotal evidence suggests that unfamiliar languages sound faster than one’s native language. Empirical evidence for this impression has, so far, come from explicit rate judgments. The aim of the present study was to test whether such perceived rate differences between native and foreign languages (FLs) have effects on implicit speech processing. Our measure of implicit rate perception was “normalization for speech rate”: an ambiguous vowel between short /a/ and long /a:/ is interpreted as /a:/ following a fast but as /a/ following a slow carrier sentence. That is, listeners did not judge speech rate itself; instead, they categorized ambiguous vowels whose perception was implicitly affected by the rate of the context. We asked whether a bias towards long /a:/ might be observed when the context is not actually faster but simply spoken in a FL. A fully symmetrical experimental design was used: Dutch and German participants listened to rate matched (fast and slow) sentences in both languages spoken by the same bilingual speaker. Sentences were followed by non-words that contained vowels from an /a-a:/ duration continuum. Results from Experiments 1 and 2 showed a consistent effect of rate normalization for both listener groups. Moreover, for German listeners, across the two experiments, foreign sentences triggered more /a:/ responses than (rate matched) native sentences, suggesting that foreign sentences were indeed perceived as faster. Moreover, this FL effect was modulated by participants’ ability to understand the FL: those participants that scored higher on a FL translation task showed less of a FL effect. However, opposite effects were found for the Dutch listeners. For them, their native rather than the FL induced more /a:/ responses. Nevertheless, this reversed effect could be reduced when additional spectral properties of the context were controlled for. Experiment 3, using explicit rate judgments, replicated the effect for German but not Dutch listeners. We therefore conclude that the subjective impression that FLs sound fast may have an effect on implicit speech processing, with implications for how language learners perceive spoken segments in a FL.

Temporal contrast effects in human speech perception are immune to selective attention

“…This indicates that the neurobiological mechanisms underlying these two forms of acoustic context effects are likely to differ (sustained entrained neural oscillators vs. adaptive gain control 20,33,53 ). In www.nature.com/scientificreports www.nature.com/scientificreports/ particular, context effects induced by higher-level properties of language (e.g., based on talker-identity, language, and situation-specific expectations 45,46,[54][55][56] ) are likely to be influenced by attention. This advocates a two-stage model of the influence of acoustic context effects 29 , where the earliest perceptual effects are of general auditory nature and unaffected by attention.…”

Listening to yourself is special: Evidence from global speech rate tracking

“…The second stage involves domain-specific cognitive adjustments performed later in time (rather than perceptual normalization), after talker segregation. Here, word recognition may be modulated by comparing the speech input to an expected form considering a certain speech context or talker [ 19 , 56 , 57 ]. Therefore, talker-specific global speech rate effects, such as the effect reported in Maslowski et al [ 31 ], likely occur during the second stage.…”

Knowledge-based and signal-based cues are weighted flexibly during spoken language comprehension.

“…Most relevant for our purposes are studies investigating contextual speech rate cues. The speech rate in a lead-in sentence can change the perception of a following target word: For instance, a vowel ambiguous between short /ɑ/ and long /a:/ in Dutch is perceived as /a:/ in the context of a fast speech rate because it sounds relatively long compared with the short vowels in the fast context, but as /ɑ/ in the context of a slow speech rate (Bosker, 2017; Bosker & Reinisch, 2017; Maslowski et al, 2019; Reinisch & Sjerps, 2013). This process, known as rate normalization, influences many duration-cued phonemic contrasts, such as singleton-geminate (Mitterer, 2018), /b/-/p/ (Gordon, 1988), /b/-/w/ (Wade & Holt, 2005), and recognition of unstressed syllables ( form vs. forum ; Baese-Berk, Dilley, Henry, Vinke, & Banzina, 2019) and words ( silver jewelry vs. silver or jewelry ; Dilley & Pitt, 2010; cease vs. see us ; Baese-Berk et al, 2019).…”