Article

Specificity of experience dependent pitch representation in the brainstem

Center for Neural Basis of Cognition, Carnegie Mellon University, Pittsburgh, Pennsylvania, USA.
Neuroreport (Impact Factor: 1.52). 11/2006; 17(15):1601-5. DOI: 10.1097/01.wnr.0000236865.31705.3a
Source: PubMed

ABSTRACT

Crosslanguage comparisons of brainstem-evoked potentials have revealed experience-dependent plasticity in pitch representation for curvilinear f0 contours representative of Mandarin tones. To assess the tolerance limits of this experience-dependent selectivity, we evaluated cross-linguistically (Chinese, English) the pitch strength and tracking accuracy of linear rising and falling f0 ramps representative of Mandarin tones 2 and 4. No crosslanguage differences in pitch strength or accuracy were observed for either tone, indicating that stimuli with linear rising/falling ramps elicit homogeneous pitch representations at the level of the brainstem regardless of language experience. We conclude that pitch extraction at the brainstem level is critically dependent on specific dimensions of pitch contours that native speakers have been exposed to in natural speech contexts.

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Available from: Ananthanarayan Krishnan
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    • "Additionally , Chinese listeners' more salient CP for even non-speech stimuli further suggests an experience-dependent enhancement to the categorization of pitch that is domain-general but also influenced by long-term categorical representations and short/long-term memory garnered through tone-language experience (Xu et al., 2006a). Consistent with behavioral studies, neuroimaging work demonstrates that linguistic pitch experience tunes both subcortical (Bidelman et al., 2011a, 2011b; Krishnan et al., 2010; Xu et al., 2006b) and cortical (Chandrasekaran et al., 2007b; Gandour et al., 1998, 2000) encoding of pitch. Presumably, tone-languages not only enhance neural pitch representations , but also act to warp or restrict the perceptual space near category boundaries to supply a more dichotomous decision when classifying lexical tones (e.g., Bidelman and Alain, 2015; Bidelman et al., 2014b; Iverson et al., 2003). "
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    ABSTRACT: Categorical perception (CP) represents a fundamental process in converting continuous speech acoustics into invariant percepts. Using scalp-recorded event-related brain potentials (ERPs), we investigated how tone-language experience and stimulus context influence the CP for lexical tones-pitch patterns used by a majority of the world's languages to signal word meaning. Stimuli were vowel pairs overlaid with a high-level tone (T1) followed by a pitch continuum spanning between dipping (T3) and rising (T2) contours of the Mandarin tonal space. To vary context, T1 either preceded or followed the critical T2/T3 continuum. Behaviorally, native Chinese showed stronger CP as evident by their steeper, more dichotomous psychometric functions and faster identification of linguistic pitch patterns than native English-speaking controls. Stimulus context produced shifts in both groups' categorical boundary but was more exaggerated in native listeners. Analysis of source activity extracted from primary auditory cortex revealed overall stronger neural encoding of tone in Chinese compared to English, indicating experience-dependent plasticity in cortical pitch processing. More critically, "neurometric" functions derived from multidimensional scaling and clustering of source ERPs established: (i) early auditory cortical activity could accurately predict listeners' psychometric speech identification and contextual shifts in the perceptual boundary; (ii) neurometric profiles were organized more categorically in native speakers. Our data show that tone-language experience refines early auditory cortical brain representations so as to supply more faithful templates to neural mechanisms subserving pitch categorization. We infer that contextual influence on the CP for tones is determined by language experience and the frequency of pitch patterns as they occur in listeners' native lexicon. Copyright © 2015. Published by Elsevier Inc.
    Full-text · Article · Jul 2015 · NeuroImage
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    • "It is equally important to study how the potential reshaping of tone production by L2 learning relates to the perception of tonal differences, which presumably is also enhanced. Evidence for the specific effects of language experience on tone perception has been shown previously not only in behavioral research (Cooper & Wang, 2012; Francis, Ciocca, Ma, & Fenn, 2008; Lee, Vakoch, & Wurm, 1996; Wayland & Guion, 2004), but also in fMRI and ERP research (Chandrasekaran, Krishnan, & Gandour, 2007a; Chandrasekaran, Krishnan, & Gandour, 2007b; Chandrasekaran, Krishnan, & Gandour, 2009b; Kaan, Barkley, Bao, & Wayland, 2008; Krishnan, Xu, Gandour, & Cariani, 2005; Van Lancker & Fromkin, 1973; Wang et al., 2001, 2003; Wong & Perrachione, 2007; Xu, Krishnan, & Gandour, 2006). For instance, native Mandarin speakers outperformed native English speakers in discriminating between the Thai mid tone and low tone, suggesting that the perception ability gained by using one tone system may be transferable to a different tone system (Wayland & Guion, 2004). "
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    ABSTRACT: To perceive and produce Mandarin, adult second language (L2) learners need to learn to discriminate lexical pitch variations and develop the new sensorimotor skills needed to produce the lexical tones. In this paper, we investigated whether auditory discrimination and sensorimotor integration differ with Mandarin (tonal) language experience in the context of tonal language syllables and simple sustained vowels. We tested four distinct groups: native Mandarin speakers, Mandarin L2 adults, trained vocalists, and naïve adults (those with no tonal language exposure). Auditory discrimination was measured using two perceptual tasks, musical tone discrimination and Mandarin tone discrimination, the results of which were compared across the four groups. Group differences in sensorimotor integration related to lexical tone production were examined with a pitch-shift paradigm that assessed rapid motor responses to unexpected pitch perturbations. Mandarin speakers performed significantly better on Mandarin tone discrimination compared to the other three groups. Mandarin speakers also showed more attenuation of pitch-shift response amplitude (better vocal pitch control) during production of both the sustained vowel and Mandarin tones, especially compared to naïve speakers. These findings suggest that Mandarin speakers have more robust pitch control over self-produced vocalizations and are thus less affected by auditory feedback perturbations. This effect was particularly evident in response to the Mandarin high level lexical tone, for which the pitch-shift compensation patterns (with apparent attenuation in Mandarin speakers only) differed qualitatively from those of sustained vowels (with clear compensation in all groups), the rising tone (with apparent attenuation in all groups but naïve speakers), and the falling tone (with apparent attenuation in all groups). Trained vocalists also appear to rely more than naïve speakers on internal models when regulating voice F0 in the nonlinguistic domain (sustained vowel), but not in the linguistic domain (Mandarin tone). Native Mandarin speakers demonstrate robust internal models for lexical tone in both perception and production; this underscores the importance of developmental language experience but also provides evidence for the declination of the high level lexical tone which requires a mastery of tonal languages.
    Full-text · Article · Jan 2015 · Journal of Phonetics
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    • "The scalp-recorded FFR to voice pitch has been reported recently with results that correlate with behavioral tests of pitch perception (Akhoun et al., 2008; Skoe et al., 2010; Krishnan et al., 2012). Among the stimulus tokens that had been utilized in the FFR research, Mandarin Chinese syllables that contain different f0 contours and lexical meanings have been widely used (Krishnan et al., 2004, 2009; Xu et al., 2006; Wong et al., 2007; Song et al., 2008; Jeng et al., 2010, 2011a, 2011b, 2011c, 2011d; Li & Jeng, 2011). Several aspects of the voice pitch elicited FFR have been examined. "
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    ABSTRACT: The frequency-following response (FFR) to voice pitch has been widely examined in research laboratories and has demonstrated its potential to be transformed into a useful tool for patients with hearing, speech, and language disorders in the clinic. During the past decade, many aspects of the FFR have been reported. The presence of such a response, however, still relies on subjective interpretation of the observer. Aside from a recent study reporting two algorithms for detecting such a response, there has been limited number of studies reporting the development of an automated procedure for FFR. The purpose of this study is (1) to develop an automated procedure that utilizes the statistical properties of the temporal and spectral energy distributions in the recorded waveforms and (2) to explore the effectiveness, accuracy, and efficiency of the automated procedure and compare them with those obtained from conventional algorithms and human judgments.
    Preview · Article · May 2013 · The Journal of the Acoustical Society of America
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