Mandarin-speaking Children With Cochlear Implants Face Challenges in Using F0 Expansion to Express Contrastive Focus.

OBJECTIVES: Children with cochlear implants (CIs) face challenges in perceiving fundamental frequency (F0) information because CIs do not transmit F0 effectively. In Mandarin, F0 can contrast meanings at the word level, that is, via lexical tones with distinct F0 contours, and signal contrastive relations between words at the utterance-level, that is, via contrastive focus with expanded F0 range and longer duration. Mandarin-speaking children with CIs have been reported to face challenges in producing distinct F0 contours across tones, but early implantation facilitates tonal acquisition. However, it is still unclear if utterance-level prosody, such as contrastive focus, is also challenging for these children, and if early implantation also offers benefits for focus production. Therefore, this study asked how accurately children with CIs can produce contrastive focus, and if early implantation leads to more accurate focus production, with acoustic patterns approaching that of children with typical hearing (TH). DESIGN: Participants included 55 Mandarin-speaking children (3 to 7 years) with CIs and 55 age-matched children with TH. Children produced noun phrases with and without contrastive focus, such as RED-COLORED cat versus red-colored cat. Three adult native listeners perceptually scored the productions as correct or incorrect. The "correct" productions were then acoustically analyzed in terms of F0 range and duration. RESULTS: Based on the perceptual scores, children with CIs produced focus with significantly lower accuracy (38%) than their TH peers (84%). The acoustic analysis on their "correct" productions showed that children with TH used both F0 and duration to mark focus, producing focal syllables with an expanded F0 range and long duration, and postfocal syllables with a reduced F0 range and short duration. However, children with CIs differed from children with TH in that they produced focal syllables with long duration but not an expanded F0 range, although they produced postfocal syllables with a reduced F0 range and short duration like their TH peers. In addition, early implantation correlated with the percept of more accurate focus productions and better use of F0 range in focal marking. CONCLUSIONS: This study finds that Mandarin-speaking children with CIs are still learning to apply appropriate acoustic cues to contrastive focus. The challenge appears to lie in the use of an expanded F0 range to mark focus, probably related to the limited transmission of F0 information through the CI devices. These findings thus have implications for parents and those working with children with CIs, showing that utterance-level prosody also requires speech remediation, and underscores the critical role of identifying problems early in the acquisition of F0 functions in Mandarin, not only at the word level but also at the utterance-level.

The production of /s/-stop clusters by pre-schoolers with hearing loss.

Producing word-initial /s/-stop clusters can be a challenge for English-speaking pre-schoolers. For children with hearing loss (HL), fricatives can be also difficult to perceive, raising questions about their production and representation of /s/-stop clusters. The goal of this study was therefore to determine if pre-schoolers with HL can produce and represent the /s/ in word-initial /s/-stop clusters, and to compare this to their normal hearing (NH) peers. Based on both acoustic and perceptual analysis, we found that children with HL had little /s/-omission, suggesting that their phonological representation of these clusters closely aligns with that of their NH peers.

The acquisition of contrastive focus during online sentence-comprehension by children learning mandarin Chinese.

Contrastive focus, conveyed by prosodic cues, marks important information. Studies have shown that 6-year-olds learning English and Japanese can use contrastive focus during online sentence comprehension: focus used in a contrastive context facilitates the identification of a target referent (speeding up processing), whereas focus used inappropriately in a noncontrastive context misleads listeners to predict an incorrect referent, hindering the identification process (Ito et al., 2012, 2014). In Mandarin Chinese, the mapping between prosodic form and contrastive focus is less transparent, potentially delaying the acquisition of contrastive focus. This study assessed the online processing of contrastive focus by 196 Mandarin-speaking 4-10-year-olds and 34 adults in China, using the visual world paradigm. Stimuli contained a target NP in a mini discourse, with focus being used in contrastive (Experiment 1) versus Noncontrastive contexts (Experiment 2). Experiment 1 showed that the appropriate use of prosodic form for contrastive focus facilitated the identification of a target referent for 7-10-year-olds and adults, though not younger children. Experiment 2 showed that the inappropriate use of prosodic form for contrastive focus slowed the identification process only for 10-year-olds and adults. Thus, whereas 7-10-year-olds are sensitive to prosodic form for contrastive focus, only 10-year-olds use it as a primary cue to predict an upcoming referent like adults. The acquisition of contrastive focus in Mandarin is therefore a gradual process, with children showing sensitivity to contrastive focus during the early school years, and developing adult-like form-function mapping between prosody and focus until the end of primary school. (PsycInfo Database Record (c) 2023 APA, all rights reserved).

The acoustic realization of contrastive focus by 6-year-old Australian English-speaking children.

Children as young as five have some ability to produce contrastive focus [Wells et al. (2004) J. Child Lang. 31, 749-778]. However, adult listeners' ability to identify the location of contrastive focus depends on whether the speech came from a 4-, 7-, or 11-year-old [Patel and Brayton (2009) J. Speech. Lang. Hear. Res. 52, 790-801]. Recent acoustic studies have also reported the use of F0 vs duration in contrastive focus productions by American English-speaking 2-year-olds [Thorson and Morgan (2021) J. Child Lang. 48, 541-568] and 4-year-olds [Wonnacott and Watson (2008) Cognition 107, 1093-1101], respectively. This study, therefore, evaluated the extent to which older 6-year-olds, with more language experience, used F0 and/or duration when producing contrastive focus, and compared this to adult speech. Monosyllabic and disyllabic adjective + noun targets (e.g., green ball) in utterance medial and final position were elicited from 20 Australian English-speaking 6-year-olds and 14 adults in adjective focus and noun focus conditions. Although both adults and children used high F0, only adults consistently used word and stressed syllable duration as well. This suggests that children may master the different acoustic cues to contrastive focus at different stages of development, with late cue integration.

The combined effects of contextual predictability and noise on the acoustic realisation of German syllables.

Speakers tend to speak clearly in noisy environments, while they tend to reserve effort by shortening word duration in predictable contexts. It is unclear how these two communicative demands are met. The current study investigates the acoustic realizations of syllables in predictable vs unpredictable contexts across different background noise levels. Thirty-eight German native speakers produced 60 CV syllables in two predictability contexts in three noise conditions (reference = quiet, 0 dB and -10 dB signal-to-noise ratio). Duration, intensity (average and range), F0 (median), and vowel formants of the target syllables were analysed. The presence of noise yielded significantly longer duration, higher average intensity, larger intensity range, and higher F0. Noise levels affected intensity (average and range) and F0. Low predictability syllables exhibited longer duration and larger intensity range. However, no interaction was found between noise and predictability. This suggests that noise-related modifications might be independent of predictability-related changes, with implications for including channel-based and message-based formulations in speech production.

Jellybeans or Jelly, Beans ? 5-6-year-olds can identify the prosody of compounds but not lists.

Learning to use word versus phrase level prosody to identify compounds from lists is thought to be a protracted process, only acquired by 11 years (Vogel & Raimy, 2002). However, a recent study has shown that 5-year-olds can use prosodic cues other than stress for these two structures in production, at least for early-acquired noun-noun compounds (Yuen et al., 2021). This raises the question of whether children this age can also use naturally-produced prosody to identify noun-noun compounds from their list forms in comprehension. The results show that 5-6-year-olds (N = 28) can only identify compounds. Unlike adults, children as a group could not use boundary cues to identify lists and were significantly slower in their processing compared to adults. This suggests that the acquisition of word level prosody may precede the acquisition of phrase level prosody, i.e., some higher-level aspects of phrasal prosody may take longer to acquire.

The Acquisition of Acoustic Cues to Onset and Coda Voicing Contrasts by Preschoolers With Hearing Loss.

PURPOSE: Children with hearing loss (HL), including those with hearing aids (HAs) and cochlear implants (CIs), often have difficulties contrasting words like " b each" versus " p each" and "do g " versus "do ck " due to challenges producing systematic voicing contrasts. Even when acoustic contrasts are present, these may not be perceived as such by others. This can cause miscommunication, leading to poor self-esteem and social isolation. Acoustic evidence is therefore needed to determine if these children have established distinct voicing categories before entering school and if misperceptions are due to a lack of phonological representations or due to a still-maturing implementation system. The findings should help inform more effective early intervention. METHOD: Participants included 14 children with HL (eight HA users, five CI users, and one bimodal) and 20 with normal hearing, all English-speaking preschoolers. In an elicited imitation task, they produced consonant-vowel-consonant minimal pair words that contrasted voicing in word-initial (onset) or word-final (coda) position at all three places of articulation (PoAs). RESULTS: Overall, children with HL showed acoustically distinct voicing categories for both onsets and codas at all three PoAs. Contrasts were less systematic for codas than for onsets, as also confirmed by adults' perceptual ratings. CONCLUSIONS: Preschoolers with HL produce acoustic differences for voiced versus voiceless onsets and codas, indicating distinct phonological representations for both. Nonetheless, codas were less accurately perceived by adult raters, especially when produced by CI users. This suggests a protracted development of the phonetic implementation of codas, where CI users, in particular, may benefit from targeted intervention.

Longer Cochlear Implant Experience Leads to Better Production of Mandarin Tones for Early Implanted Children.

OBJECTIVES: Children with cochlear implants (CIs) face challenges in acquiring tones, since CIs do not transmit pitch information effectively. It has been suggested that longer CI experience provides additional benefits for children implanted early, enabling them to achieve language abilities similar to that of normal-hearing (NH) children (Colletti 2009). Mandarin is a tonal language with four lexical tones and a neutral tone (T0), characterized by distinct pitch and durational patterns. It has been suggested that early implantation (i.e., before 2 years) greatly benefits the acquisition of Mandarin tones by children with CIs (Tang et al. 2019c). In this study, we extend those findings to investigate the effect of CI experience on the acquisition of Mandarin tones for children implanted early. We asked the extent to which they were able to produce distinct pitch and durational patterns of both lexical tones and T0 as a function of CI experience, and the extent to which their tonal productions were acoustically like that of NH children. DESIGN: Forty-four NH 3-year olds and 28 children implanted with CIs between 1 and 2 years, aged 3 to 7, were recruited. The children with CIs were grouped according to the length of CI experience: 3 to 6 years, 2 to 3 years, and 1 to 2 years. Lexical tone and T0 productions were elicited using a picture-naming task. Tonal productions from the children with CIs were acoustically analyzed and compared with those from the NH children. RESULTS: Children with 3 to 6 years of CI experience were able to produce distinct pitch and durational patterns for both lexical tones and T0, with NH-like acoustic realizations. Children with 2 to 3 years of CI experience were also able to produce the expected tonal patterns, although their productions were not yet NH-like. Those with only 1 to 2 years of CI experience, however, were not yet able to produce the distinct acoustic patterns for either lexical tones or T0. CONCLUSIONS: These results provide acoustic evidence demonstrating that, when Mandarin-speaking children are implanted before the age of 2, only those with 3 to 6 years of experience were able to produce NH-like tones, including both lexical tone and T0. Children with shorter CI experience (less than 3 years) were unable to produce distinct acoustic patterns for the different tones. This suggests that at least 3 years of CI experience is still needed for early implanted children to acquire tonal distinctions similar to those of NH 3-year olds.

Acoustic cues to coda stop voicing contrasts in Australian English-speaking children.

While voicing contrasts in word-onset position are acquired relatively early, much less is known about how and when they are acquired in word-coda position, where accurate production of these contrasts is also critical for distinguishing words (e.g., dog vs. dock). This study examined how the acoustic cues to coda voicing contrasts are realized in the speech of 4-year-old Australian English-speaking children. The results showed that children used similar acoustic cues to those of adults, including longer vowel duration and more frequent voice bar for voiced stops, and longer closure and burst durations for voiceless stops along with more frequent irregular pitch periods. This suggests that 4-year-olds have acquired productive use of the acoustic cues to coda voicing contrasts, though implementations are not yet fully adult-like. The findings have implications for understanding the development of phonological contrasts in populations for whom these may be challenging, such as children with hearing loss.

Temporal cues to onset voicing contrasts in Australian English-speaking children.

Voicing contrasts are lexically important for differentiating words in many languages (e.g., "bear" vs "pear"). Temporal differences in the voice onset time (VOT) and closure duration (CD) contribute to the voicing contrast in word-onset position. However, little is known about the acoustic realization of these voicing contrasts in Australian English-speaking children. This is essential for understanding the challenges faced by those with language delay. Therefore, the present study examined the VOT and CD values for word-initial stops as produced by 20 Australian English-speaking 4-5-year-olds. As anticipated, these children produced a systematic distinction between voiced and voiceless stops at all places of articulation (PoAs). However, although the children's VOT values for voiced stops were similar to those of adults, their VOTs for voiceless stops were longer. Like adults, the children also had different CD values for voiced and voiceless categories; however, these were systematically longer than those of adults. Even after adjusting for temporal differences by computing proportional ratios for the VOT and CD, children's voicing contrasts were not yet adultlike. These results suggest that children of this age are still developing appropriate timing and articulatory adjustments for voicing contrasts in the word-initial position.

Five-year-olds produce prosodic cues to distinguish compounds from lists in Australian English.

Although previous research has indicated that five-year-olds can use acoustic cues to disambiguate compounds (N1 + N2) from lists (N1, N2) (e.g., 'ice-cream' vs. 'ice, cream') (Yoshida & Katz, 2004, 2006), their productions are not yet fully adult-like (Wells, Peppé & Goulandris, 2004). The goal of this study was to examine this issue in Australian English-speaking children, with a focus on their use of F0, word duration, and pauses. Twenty-four five-year-olds and 20 adults participated in an elicited production experiment. Like adults, children produced distinct F0 patterns for the two structures. They also used longer word durations and more pauses in lists compared to compounds, indicating the presence of a boundary in lists. However, unlike adults, they also inappropriately inserted more pauses within the compound, suggesting the presence of a boundary in compounds as well. The implications for understanding children's developing knowledge of how to map acoustic cues to prosodic structures are discussed.

The development of abstract representations of tone sandhi.

Phonological processes result in surface variants of the same words across phonological contexts, posing potential word learning challenges for children. Mandarin tone sandhi is a tonal process changing Tone 3 (T3) in different tonal and syntactic contexts, resulting in allophonic variants of T3 in connected speech. Previous studies found that Mandarin-learning 3-year-olds were able to productively apply tone sandhi processes in novel compounds, correctly using the allophonic variants of T3 in appropriate tone sandhi contexts (Tang et al., 2018, 2019). However, it remains unclear how these variants are represented in children's mental lexicon. This study, therefore, examined Mandarin-learning children's perceptual representation of allophonic variants of T3. Ninety-four 3- to 5-year-olds and 29 adults were tested. Sensitivity to allophonic mispronunciations of T3 syllables in novel tone sandhi compounds was measured using a visual fixation procedure. The results showed that children, like adults, treated tone sandhi mispronunciations as target-like. Thus, in recognizing novel tone sandhi words, Mandarin-speaking children exhibit flexibility in accommodating the allophonic variants of T3, suggesting that they have developed an abstract T3 category in their mental lexicon. The findings reveal the effect of phonological processes in shaping children's phonological representations. (PsycINFO Database Record (c) 2019 APA, all rights reserved).

The Acquisition of Mandarin Tonal Processes by Children With Cochlear Implants.

Purpose Children with cochlear implants (CIs) face challenges in acquiring tonal languages, as CIs do not efficiently code pitch information. Mandarin is a tonal language with lexical tones and tonal processes such as neutral tone and tone sandhi, exhibiting contextually conditioned tonal realizations. Previous studies suggest that early implantation and long CI experience facilitate the acquisition of lexical tones by children with CIs. However, there is lack of acoustic evidence on children's tonal productions demonstrating that this is the case, and it is unclear whether and how children with CIs are able to acquire contextual tones. This study therefore examined the acoustic realization of both lexical tones and contextual tones as produced by children fitted with CIs, exploring the potential effects of age at implantation and length of CI experience on their acquisition of the Mandarin tonal system. Method Seventy-two Mandarin-learning preschoolers with CIs, varying in age at implantation (13-42 months) and length of CI experience (2-49 months), and 44 normal hearing 3-year-old controls were recruited. Tonal productions were elicited from both groups using picture-naming tasks and acoustically compared. Results Only the early implanted group (i.e., implanted before the age of 2 years) produced normal-like lexical tones and generally had contextual tones approximating those of the normal-hearing children. The other children, including those with longer CI experience, did not have typical tonal productions; their pitch patterns for lexical tones tended to be flatter, and contextual tone productions were unchanged across tonal contexts. Conclusion Children with CIs face challenges in acquiring Mandarin tones, but early implantation may help them to develop normal-like lexical tone categories, which further facilitates their implementation of contextual tones. Supplemental Material https://doi.org/10.23641/asha.8038889.

Acquisition of weak syllables in tonal languages: acoustic evidence from neutral tone in Mandarin Chinese.

Weak syllables in Germanic and Romance languages have been reported to be challenging for young children, with syllable omission and/or incomplete reduction persisting till age five. In Mandarin Chinese, neutral tone (T0) involves a weak syllable with varied pitch realizations across (preceding) tonal contexts and short duration. The present study examined how and when T0 was acquired by 108 Beijing Mandarin-speaking children (3-5 years) relative to 33 adult controls. Lexicalized (familiar) and non-lexicalized (unfamiliar) T0 words were elicited in different preceding tonal contexts. Unlike previous reports, the present study revealed that children as young as three years have already developed a phonological category for T0, exhibiting contextually conditioned tonal realizations of T0 for both familiar and unfamiliar items. However, mastery of adult-like pitch and duration implementation of T0 is a protracted process not completed until age five. The implications for the acquisition of weak syllables more generally are discussed.

Five-Year-olds' Acoustic Realization of Mandarin Tone Sandhi and Lexical Tones in Context Are Not Yet Fully Adult-Like.

Large numbers of children around the world are learning tone languages, but few studies have examined the acoustic properties of children's early tone productions. Even more scarce are acquisition studies on tone sandhi, a tone change phenomenon which alters the surface realization of lexical tones. Two studies using perceptual coding report the emergence of lexical tone and tone sandhi at around 2 years (Li and Thompson, 1977; Hua and Dodd, 2000). However, the only acoustic study available shows that 3-year-olds are not yet adult-like in their lexical tone productions (Wong, 2012). This raises questions about when children's productions become acoustically adult-like and how their tone productions differ from those of adults. These questions were addressed in the current study which compared Mandarin-speaking pre-schoolers' (3-5-year-olds) tone productions to that of adults. A picture naming task was used with disyllabic real words familiar to pre-schoolers. Overall children produced appropriate tone contours for all tones, i.e., level for tone 1, rising for tones 2, 3 and full sandhi, falling for tone 4 and half sandhi. However, children's productions were not adult-like for tones 3, 4, and the sandhi forms, in terms of coordinating pitch range, slope and curvature, with little evidence of development across ages. These results suggest a protracted process in achieving adult-like acoustic realization of both lexical and sandhi tones.

Acoustic realization of Mandarin neutral tone and tone sandhi in infant-directed speech and Lombard speech.

Mandarin lexical tones are modified in both infant-directed speech (IDS) and Lombard speech, resulting in tone hyperarticulation. However, it is unclear if these registers also alter contextual tones (neutral tone and tone sandhi) and if such phonetic modification might affect acquisition of these tones. This study therefore examined how neutral tone and tone sandhi are realized in IDS, and how their acoustic manifestations compare with those in Lombard speech, where the communicative needs of listeners differ. Neutral tone and tone sandhi productions were elicited from 15 Mandarin-speaking mothers during (1) interactions with their 12-month-old infants (IDS), (2) in conversation with a Mandarin-speaking adult in a noisy environment (Lombard speech), and (3) in conversation with a Mandarin-speaking adult in a quiet environment (adult-directed speech). The results showed that, although both contextual tones were modified in IDS and Lombard speech, their key tone features were maintained. In addition, IDS and Lombard speech modified these tones differently: IDS increased pitch height and modified pitch contour, while Lombard speech increased pitch height only. The realization of neutral tone and tone sandhi across registers is discussed with reference to listeners' different communicative needs.

Phonetic enhancement of Mandarin vowels and tones: Infant-directed speech and Lombard speech.

Speech units are reported to be hyperarticulated in both infant-directed speech (IDS) and Lombard speech. Since these two registers have typically been studied separately, it is unclear if the same speech units are hyperarticulated in the same manner between these registers. The aim of the present study is to compare the effect of register on vowel and tone modification in the tonal language Mandarin Chinese. Vowel and tone productions were produced by 15 Mandarin-speaking mothers during interactions with their 12-month-old infants during a play session (IDS), in conversation with a Mandarin-speaking adult in a 70 dBA eight-talker babble noise environment (Lombard speech), and in a quiet environment (adult-directed speech). Vowel space expansion was observed in IDS and Lombard speech, however, the patterns of vowel-shift were different between the two registers. IDS displayed tone space expansion only in the utterance-final position, whereas there was no tone space expansion in Lombard speech. The overall pitch increased for all tones in both registers. The tone-bearing vowel duration also increased in both registers, but only in utterance-final position. The difference in speech modifications between these two registers is discussed in light of speakers' different communicative needs.

Planning of Hiatus-Breaking Inserted /ɹ/ in the Speech of Australian English-Speaking Children.

Purpose: Non-rhotic varieties of English often use /ɹ/ insertion as a connected speech process to separate heterosyllabic V1.V2 hiatus contexts. However, there has been little research on children's development of this strategy. This study investigated whether children use /ɹ/ insertion and, if so, whether hiatus-breaking /ɹ/ can be considered planned, as evidenced by F3 lowering on V1. Method: Thirteen Australian English-speaking children (7 girls, 6 boys; mean age 6;1 [years;months]) participated in an elicited production task. The stimuli included carrier sentences containing 4 test words (linking /ɹ/ context: door, floor; intrusive /ɹ/ context: paw, claw) followed by of (e.g., "This is the paw of the cat"). After familiarization containing auditory and picture prompts, children produced test sentences upon presentation of picture prompts alone. Results: Eight children produced /ɹ/ insertion; the others used (some) glottalization. The incidence of /ɹ/ did not vary across linking or intrusive contexts, and inserted /ɹ/ was associated with F3 lowering at V1 onset relative to control items without /ɹ/. Conclusion: Six-year-old Australian English-speaking children who use /ɹ/ insertion show evidence of planning ahead and inserting /ɹ/ as a segment. The implications for the development of speech-planning processes and phonological and lexical representations are discussed.

Discourse Strategies and the Production of Prosody by Prelingually Deaf Adolescent Cochlear Implant Users.

OBJECTIVES: The purpose of this study is to assess the use of discourse strategies and the production of prosody by prelingually deaf adolescent users of cochlear implants (CIs) when participating in a referential communication task. We predict that CI users will issue more directives (DIRs) and make less use of information requests (IRs) in completing the task than their normally hearing (NH) peers. We also predict that in signaling these IRs and DIRs, the CI users will produce F0 rises of lesser magnitude than the NH speakers. DESIGN: Eight prelingually deaf adolescent CI users and 8 NH adolescents completed a referential communication task, where participants were required to direct their interlocutor around a map. Participants were aged from 12.0 to 14.2 years. The mean age at implantation for the CI group was 2.1 years (SD 0.9). The use of IRs, DIRs, acknowledgments, and comments was compared between the two groups. The use and magnitude of fundamental frequency (F0) rises on IRs and DIRs was also compared. RESULTS: The CI users differed from the NH speakers in how they resolved communication breakdown. The CI users showed a preference for repeating DIRs, rather than seeking information as did the NH speakers. A nonparametric Mann-Whitney U test indicated that the CI users issued more DIRs (U = 8, p = 0.01), produced fewer IRs (U = 13, p = 0.05) and fewer acknowledgments (U = 5, p = 0.003) than their NH counterparts. The CI users also differed in how they used F0 rises as a prosodic cue to signal IRs and DIRs. The CI users produced larger F0 rises on DIRs than on IRs, a pattern opposite to that displayed by the NH speakers. An independent samples t-test revealed that the CI users produced smaller rises on IRs compared with those produced by the NH speakers [t(12) = -2.762, p = 0.02]. CONCLUSIONS: The CI users differed from the NH speakers in how they resolved communication breakdown. The CI users showed a preference for repeating DIRs, rather than seeking information to understand their interlocutor's point of view. Their use of prosody to signal discourse function also differed from their NH peers. These differences may indicate a lack of understanding of how prosody is used to signal discourse modality by the CI users. This study highlights the need for further research focused on the interaction of prosody, discourse, and language comprehension.

The Use of Prosodic Cues in Sentence Processing by Prelingually Deaf Users of Cochlear Implants.

OBJECTIVES: The purpose of this study is to assess the use of prosodic and contextual cues to focus by prelingually deaf adolescent users of cochlear implants (CIs) when identifying target phonemes. We predict that CI users will have slower reaction times to target phonemes compared with a group of normally-hearing (NH) peers. We also predict that reaction times will be faster when both prosodic and contextual (semantic) cues are provided. DESIGN: Eight prelingually deaf adolescent users of CIs and 8 adolescents with NH completed 2 phoneme-monitoring experiments. Participants were aged between 13 and 18 years. The mean age at implantation for the CI group was 1.8 years (SD: 1.0). In the prosodic condition, reaction times to a target phoneme in a linguistically focused (i.e., stressed) word were compared between the two groups. The semantic condition compared reaction time with target phonemes when contextual cues to focus were provided in addition to prosodic cues. RESULTS: Reaction times of the CI group were slower than those of the NH group in both the prosodic and semantic conditions. A linear mixed model was used to compare reaction times using Group as a fixed factor and Phoneme and Subject as random factors. When only prosodic cues (prosodic condition) to focus location were provided, the mean reaction time of the CI group was 512 msec compared with 317 msec for the NH group, and this difference was significant (p < 0.001). The provision of contextual cues speeded reaction times for both groups (semantic condition), indicating that top-down processing aided both groups in their search for a focused item. However, even with both prosodic and contextual cues, the CI users' processing times remained slower, compared with the NH group, with mean reaction times of 385 msec for the CI users but 232 msec for the NH listeners (p < 0.001). CONCLUSIONS: Prelingually deaf CI users' processing of prosodic cues is less efficient than that of their NH peers, as evidenced by slower reaction times to targets in phoneme monitoring. The provision of contextual cues speeded reaction times for both NH and CI groups, although the CI users were slower in responding than the NH group. These findings contribute to our understanding of how CI users employ/integrate prosodic and semantic cues in speech processing.