Examination of perceptual reorganization for nonnative speech contrasts: Zulu click discrimination by English-speaking adults and infants.

“However, by 12 months of age, infants lose their sensitivity to contrasts not present in their native language and show a language-specific pattern of discrimination (Werker and Tees 1984; Best et al. 1988; Bosch and Sebastian-Galles 2003).”

“Note that this prediction is not as simple as suggesting that similar languages should be learned more easily; in some cases, similarity can be harmful.(80) Exploring this prediction may help to explain some of the variability observed in previous reports of language learning in adulthood; while many adults learn new…”

“…languages perceive different categories in the same signal [see e.g., Aslin and Pisoni, 1980; Werker and Tees, 1984; Werker and Logan, 1985; Best et al., 1988; Kuhl et al., 1992; Vihman, 1996], and therefore the role of perception in phonology cannot be fully understood without attention…”

“These biases emerge when children’s speech perception becomes tuned to the language they are acquiring, typically around the end of the first year of life (Best and McRoberts, 2003; Best et al., 1988; Kuhl et al., 1992; Nittrouer and Lowenstein, 2010; Werker and Lalonde, 1988; Werker et al., 1998).”

“Indeed, other studies have shown that not only consonants but also the perception of vowels is influenced by one's native language (Best et al., 1988; Kuhl et al., 1992).”

“clicks for speakers of non-click languages) are likely not to be assimilated (Best et al., 1988).”

“Examination of perceptual reorganization for nonnative speech contrasts: Zulu click discrimination by English-speaking adults and infants.”

“Although there are exceptions to this pattern (Best et al., 1988; L. Liu & Kager, 2014, 2016; Mattock & Burnham, 2006; Mazuka et al., 2014; Mugitani et al., 2009; Polka & Bohn, 1996; Polka et al., 2001; Sundara et al., 2006; Yeung et al., 2013), it is clear that infants’ perception”

“Introducing allophonic changes by using a different consonantal context in the X position made it possible to test a more natural situation of vowel identification, giving the task more ecological validity by involving perceptual constancy competence (Best et al., 1988).”

“…perception, there is a broad base of evidence to suggest that infants begin their lives, no matter where they are raised, with universal capacities for speech discrimination (Trehub, 1976; Aslin et al., 1981; Werker et al., 1981;Werker and Tees, 1984; Best et al., 1988; Polka and Werker, 1994).”

“While both Flege’s SLM and Best’s PAM and PAM-L2 are intuitively appealing, and a large body of experimental results have been interpreted within both frameworks (Best et al., 1988, 2001; Best and Strange, 1992; Flege, 1987; Hallé et al., 1999), the proposals suffer from a significant limitation.”

“Frontiers in Neuroscience | Auditory Cognitive Neuroscience August 2014 | Volume 8 | Article 238 | 4 an existing native-language category, are notoriously difficult to acquire in adulthood (Best et al., 1988).”

“Within a trial, different tokens of the syllables from the same tonal category were used to force listeners to discriminate categorically rather than acoustically (Best et al., 1988; Polka, 1991, 1992), thereby increasing the likelihood of finding language-specific effects.”

“Best, McRoberts, and Sithole (1988) and Best, McRoberts, LaFleur, and Silver-Isenstadt (1995) developed a perceptual assimilation model (PAM) to account for variability in native speech understanding by nonnative listeners.”

“…by means of a hierarchy of possible perceptual relations among sounds, on the basis of some kind of perceived phonetic distance (auditory, acoustic, articulatory); see the Perceptual Assimilation Model (Best, 1995; Best et al., 1988), or the Perceptual Magnet Effect as theorized in Kuhl (1991).”

“…more frequently in a particular language (Anderson et al., 2003), and some salient non-native contrasts remain discriminable after the 1st year (Best et al., 1988) while some non-salient native contrasts require more than 6 months of exposure to become discriminable (e.g., Narayan et al.,…”

“2.3 Predictions Given the widely attested effect of language-specific phonotactic knowledge on speech perception (Best et al., 1988; Kuhl et al., 1992), it is reasonable to expect that listeners will perform well in identifying place and secondary articulation contrasts in the contexts…”

“In contrast, CE infants are exposed to larger F1 than F2 distinctions for these three vowels, which is the explanation given in Curtin et al. (2009) for their asymmetric findings.”

“We expected infants to exhibit longer looking times during the novel trial than during the last habituation trial if they noticed the differences between the stress patterns (Horowitz 1974; Best et al.1988; Polka & Werker 1994).”

“Infants were tested using the central fixation procedure (Best et al., 1988), which was successfully adapted by Houston et al. (2003) to assess speech perception skills in infants with CIs.”

“In contrast, other non-native perception tasks, such as Zulu click discrimination by English speakers, appear to be relatively easy (Best et al., 1988).”

“Adult speakers of different languages, on the other hand, not only differ from one another in the location of perceptual boundaries between phonetic contrasts but also lose altogether the ability to perceive some nonnative contrasts (e.g., Best et al. 1988; Logan et al. 1989).”

“, [11,12]) likely due to the relative difficulty or “acoustic salience” of particular phonemes [13], there is a general consensus that infants become “tuned” to their native phonemic inventory by the beginning of their second year [14–17].”

“First, various studies have attested the tendency in adult L2 learners to focus attention to those aspects of sounds needed for phonemic contrast (e.g. Trubetzkoy, 1939; Best et al., 1988; Boomershine et al., 2004).”

“To the extent that subjects were successful in assimilating [β] to a native segment other than [b] (an “opposing-category assimilation” in the terminology of Best et al., 1988, p. 347), the same argument applies here that is discussed below for coronals.”

“…pair contrasted in vowel duration (Dietrich et al., 2007), indicating that perceptual salience may contribute more to acoustic discrimination (e.g., Best et al., 1988; Liu and Kager, 2014; Ramachers et al., 2017) than to linguistic interpretation and as such its effect may be limited during…”

“A recent proposal by Best, McRoberts, and Sithole (1988) distinguishes four alternatives: (a) the two stimuli are assimilated to a single category; (b) the two stimuli are assimilated to opposing native language categories; (c) one stimulus is privileged because taken as representing a better…”

“Infants no longer show a universal sensitivity to all sound contrasts used in the world’s languages (Best et al., 1988; Kuhl et al., 2006; Werker and Tees, 1984), and they move beyond simply identifying or preferring familiar languages and language varieties.”

“This was in part due to the emphasis on perceptual narrowing in speech perception which argues that starting in the first year of life, infants lose the sensitivity to discriminate sounds in other languages but get better at discriminating contrasting sounds in the language that surrounds them (Best et al., 1988; Kuhl…”

“, 1982) and to distinguish between different Zulu clicks, which make use of completely novel acoustic cues (Best et al., 1988).”

“Notably, Best et al. (1988) reported that clicks are often categorized by native English listeners as nonvocal tract events such as fingers snapping (and we found some comparable responses in our phonological significance test for the isolated clicks).”

“However, the phonological learning success appears to also strongly depend on the type of phonemic contrast involved (Best et al., 1988; Dobel et al., 2009; Dupoux et al., 2008; Golestani and Zatorre, 2009).”

“It is well-established that the perception of non-native phonetic contrasts is more effortful and error-prone than that of native contrasts [see Speech Learning Model (SLM) by Flege, 1995, Perceptual assimilation model (PAM) by Best et al., 1988, Best, 1994, and Native Language Neural Commitment (NLNC) model by Kuhl,…”

“…category structure and the adult’s robust native language categories, proposing that successful learning depends heavily on how these structures are integrated (Perceptual Assimilation Model: Best et al., 1988, 2001; Speech Learning Model: Flege, 1988; 1991; for a review, see Kingston, 2003).”

“Previous studies have revealed that not all non-native contrasts are equally difficult (Best et al., 1988; Polka, 1991; Werker & Tees, 1984).”

“Best et al. (1988) examined the perception of Zulu clicks by English adults and infants to conclude that the SC was the most difficult assimilation type.”

“Moreover, clickvowel Zulu syllables that are perceived by American English listeners as non-speech (Best et al. 1988) yielded a McGurk effect as pronounced as with stop-consonantvowel syllables (Brancazio et al. 2006).”

“The Journal of the Acoustical Society of America, 106(6), 3649–3658.”

“The first is Best et al. (1988), which investigated the perception of apical, lateral and palatal clicks by English-speaking adults and found that the adults were quite successful at distinguishing the clicks.”

“It may be that some contrasts are psychoacoustically based (1), while others are assimilated to native phonemic categories (13) requiring different processing techniques for perceptual analysis.”

“Listeners described the click consonants as nonspeech “mouth sounds,” but their lack of experience with Zulu led them to perceive objectively (nonnative) speech sounds as nonspeech.”