Psychon Bull Rev (2011) 18:1035–1041 permitting the interpretation of a strong–weak stress pattern in both languages and leading to nested metrical levels (see Appendix for a list of the sentences used). Each French sentence was spoken by three female native monolingual speakers of Quebec French, and each English sentence by three female native monolingual speakers of North American English at their normal speech rate (French, mean speech rate = 4.24 syllables/s, with sentence duration = 3.08 s; English, mean speech rate = 4.23 syllables/s, with sentence duration = 3.09 s; p > .10). Phoneme boundaries were marked using Praat (Boersma & Weenik, 2007), following rules described by Ramus et al. (1999). The French and English utterances showed different acoustic properties typical of each language (Grabe & Low, 2002; Ramus et al., 1999), as shown in Table 1. French and English stimuli differed significantly in the proportion of vocalic intervals (%V), computed as the sum of vocalic intervals (onset to offset of vowel durations) divided by the total utterance duration. French and English utterances also differed in standard deviation of vocalic intervals (ΔV), but not in standard deviation of consonantal intervals (ΔC). Consistent with Grabe and Low, the normalized Pairwise Variabil- ity Index for Vocalic Intervals (V-nPVI) was signifi- cantly higher for English than for French stimuli, suggesting that English utterances exhibited a greater alternation of long and short vowels, as compared with French. We also computed a rate-normalized measure of stimulus rhythmic variability, the coefficient of variation (CV; SD/mean) of intervocalic intervals1 (IVIs; vowel onset to onset, including pauses). As is shown in Table 1, the CV(IVI) tended to be smaller for English than for French utterances. The CV(IVI) computed across every other vowel (every two words) did not differ between the French stimuli (M = .24) and English stimuli (M = .21). In sum, the French and English utterances presented typical syllable-timed and stress-timed acoustic structures, respectively. All participants were administered a questionnaire to assess their linguistic and musical experience; in addition, the Language Experience and Proficiency Questionnaire (LEAP-Q; Marian, Blumenfeld, & Kaushanskaya, 2007) was administered to the bilinguals to confirm their high level of fluency in English and French. Auditory stimuli were presented as audio files via Cubase SX software over AKG K271 studio headphones. Tapping responses 1 Consistent with previous research (Grabe & Low, 2002; Ramus et al., 1999), we assume that vowels are salient and measurable markers of speech rhythm. Analyses repeated for the CV of intersyllabic intervals showed the same pattern of results. Table 1 Means (with standard errors) of the %V, ΔV, vocalic nPVI, and CV of intervocalic intervals for the French and English utterances %V ΔV V-nPVI CV(IVI) * p < .1 *** p < .001 French Utterances 51.51 (1.01) 0.04 (0.0013) 50.45 (2.82) 0.372 (0.018) English Utterances 44.58 (0.99) 0.05 (0.0025) 62.56 (2.05) 0.330 (0.015) 1037 t(70) −4.876*** 3.616*** 3.335*** −1.739 * were recorded on a silent Roland RD700 electronic keyboard, with a temporal resolution of 1 ms. Design and procedure Participants’ spontaneous tapping rate was measured first, to identify any a priori rate preferences. They were asked to tap at a regular and comfortable pace on the (silent) keyboard with the index finger of their dominant hand, for 30 s. This was followed by the speech-tapping task, in which participants were instructed to tap along to the subjective beat they perceived in the speech segments they heard. All participants were presented with both French and English stimuli. Thus, participant group (French, English, bilingual) was a between-subjects variable, and stimulus language was a within-subjects variable. Stimuli were blocked by language; the order of language presentation was counterbalanced among participants. On each experimental trial, a spoken sentence was presented 3 times. A 350-ms high-pitched tone signaled the beginning of a trial (and thus, of a new sentence), and a low-pitched tone (300 ms) separated each of the three repetitions of the sentence within the trial. Each sentence was followed by a 1-s silence, and each tone was followed by a 700-ms silence. Participants were instructed to listen to the first presentation of the utterance and to tap along to the spoken stimulus on the second and third repetitions. There was a short break every 12 trials, whose duration was determined by the participant. Experimental trials were presented in a pseudorandom order within each language, with the restrictions that no sentence could appear twice within one subset of 12 trials and that no speaker could appear twice in a row. Thus, tapping data were collected from 72 trials in each language (12 sentences × 3 speakers × 2 repetitions). Between language blocks, all participant groups completed the linguistic and musical background questionnaires. At the