Establishing neural representations for new word forms in 12-month-old infants.

During the first year of life, infants start to learn the lexicon of their native language. Word learning includes the establishment of longer-term representations for the phonological form and the meaning of the word in the brain, as well as the link between them. However, it is not known how the brain processes word forms immediately after they have been learned. We familiarized 12-month-old infants (N = 52) with two pseudowords and studied their neural signatures. Specifically, we determined whether a newly learned word form elicits neural signatures similar to those observed when a known word is recognized (i.e., when a well-established word representation is activated, eliciting enhanced mismatch responses) or whether the processing of a newly learned word form shows the suppression of the neural response along with the principles of predictive coding of a learned rule (i.e., the order of the syllables of the new word form). The pattern of results obtained in the current study suggests that recognized word forms elicit a mismatch response of negative polarity, similar to newly learned and previously known words with an established representation in long-term memory. In contrast, prediction errors caused by acoustic novelty or deviation from the expected order in a sequence of (pseudo)words elicit responses of positive polarity. This suggests that electric brain activity is not fully explained by the predictive coding framework.

Analysis of Voice Changes in Early-Stage Parkinson's Disease with AVQI and ABI: A Follow-up Study.

OBJECTIVES: The purpose of this pilot study was to examine voice quality changes in individuals with early-stage Parkinson's disease (PD) utilizing the Acoustic Voice Quality Index (AVQI) and Acoustic Breathiness Index (ABI) over approximately a 1-year period. STUDY DESIGN: Follow-up study. METHODS: Baseline and follow-up data were gathered from the PDSTUlong speech corpus. The data for both time points included: speaker background information, sustained vowels, reading samples, and measures of PD severity (Hoehn and Yahr scores and Unified Parkinson's Disease Rating Scale III scores [UPDRS-III]). All speakers (N = 12) were native Finnish speakers. AVQIv03.01 and ABI analysis were completed in VOXplot v2.0.1. Changes in AVQI and ABI scores between baseline and follow-up were examined via causal analysis. Further, AVQI and ABI were analyzed in relation to measures of PD severity. RESULTS: Baseline mean AVQI score was 1.79 (range 0.14-4.83, SD=1.60), whereas follow-up mean AVQI score was 2.25 (range 0.55-4.53, SD=1.36). Baseline mean ABI score, in turn, was 2.92 (range 1-27 - 5.31, SD=1.57), whereas follow-up mean ABI score was 3.42 (range 1.40-5.40, SD=1.38). A significant difference was found between baseline and follow-up measures for both AVQI (Z = -2.002, P = 0.045) and ABI (Z = -2.197, P = 0.028). A significant difference in smoothed cepstral peak prominence (Z = -2.118, P = 0.034) and harmonics-to-noise ratio (Z = -1.961, P = 0.050) was also found between the two measurement periods. Change in AVQI and ABI were not correlated with the change in measures of PD severity. CONCLUSION: Over approximately 1-year, a statistical change was observed in AVQI and ABI scores, even in such a small dataset. The specific qualities of breathiness and hoarseness showed the most significant progression. Changes in voice quality were more prominent in ABI analysis.

Analysis of Voice in Parkinson's Disease Utilizing the Acoustic Voice Quality Index.

OBJECTIVES: The purpose of this study was to analyze the acoustic voice quality index (AVQI) in relation to perceptual analysis and disease stage in speakers with Parkinson's disease (PD). STUDY DESIGN: Cross-sectional study. METHODS: The following data were gathered from the Parkinson's Disease Speech corpus of Tampere University (PDSTU): prolonged vowels and reading samples from native Finnish speakers with PD (n = 34), speaker demographic information, and Hoehn and Yahr scale scores. AVQIv03.01 analysis was completed with Praat. Expert raters utilized the GRBASI scale (GRBASI: grade, roughness, breathiness, asthenia, strain, instability) to assess voice quality. AVQI scores were analyzed in relation to GRBASI ratings and disease stage, as measured by the Hoehn and Yahr scale, utilizing correlation analysis. RESULTS: AVQI scores ranged from -0.11 to 4.46 (mean = 1.64, SD = 1.39), GRBASI average total scores ranged from 0-1.83 (mean = 0.66, SD = 0.50), and Hoehn and Yahr scale scores ranged from 1- 4. A statistically significant correlation between AVQI scores and GRBASI ratings was found (rs = 0.508, P = 0.01). Several significant correlations were also found between the parameters of AVQI and scores for G, R, B and A from GRBASI. Hoehn and Yahr scores correlated significantly with GRBASI total score (rs =0.437, P = 0.01) but not with AVQI. CONCLUSION: A significant correlation was found between GRBASI ratings and Hoehn and Yahr scores, but not between AVQI and Hoehn and Yahr scores. DATA AVAILABILITY: Due to the nature of this research, participants of this study did not agree for their data to be shared publicly. Data may be made available on a case-by-case basis. Data will be available after the active phase of the study in 2028.

A comparative study of automatic vowel articulation index and auditory-perceptual assessments of speech intelligibility in Parkinson's disease.

PURPOSE: The purpose of this study was to analyse the relationship between automatic vowel articulation index (aVAI) and direct magnitude estimation (DME) among speakers with Parkinson's disease (PD) and healthy controls. We further analysed the potential of aVAI to serve as an objective measure of speech impairment in the clinical setting. METHOD: Speech samples from native Finnish speakers were utilised. Expert raters utilised DME to scale the intelligibility of speech samples. aVAI scores for PD speakers and healthy control speakers were analysed in relationship to DME speech intelligibility ratings and, among PD speakers, disease stage utilising nonparametric statistical analysis. RESULT: Mean DME intelligibility ratings were lower among PD speakers compared to healthy controls. Mean aVAI scores were nearly the same between speaker groups. DME intelligibility ratings and aVAI were strongly correlated within the PD speaker group. aVAI and DME intelligibility ratings were moderately correlated with disease stage as measured by the Hoehn and Yahr scale. CONCLUSION: aVAI was observed to be a promising tool for analysing vowel articulation in PD speakers. Further research is warranted on the application of aVAI as an objective measure of severity of speech impairment in the clinical setting, with varying patient populations and speech samples.

Non-game like training benefits spoken foreign-language processing in children with dyslexia.

Children with dyslexia often face difficulties in learning foreign languages, which is reflected as weaker neural activation. However, digital language-learning applications could support learning-induced plastic changes in the brain. Here we aimed to investigate whether plastic changes occur in children with dyslexia more readily after targeted training with a digital language-learning game or similar training without game-like elements. We used auditory event-related potentials (ERPs), specifically, the mismatch negativity (MMN), to study learning-induced changes in the brain responses. Participants were 24 school-aged Finnish-speaking children with dyslexia and 24 age-matched typically reading control children. They trained English speech sounds and words with "Say it again, kid!" (SIAK) language-learning game for 5 weeks between ERP measurements. During the game, the players explored game boards and produced English words aloud to score stars as feedback from an automatic speech recognizer. To compare the effectiveness of the training type (game vs. non-game), we embedded in the game some non-game levels stripped of all game-like elements. In the dyslexia group, the non-game training increased the MMN amplitude more than the game training, whereas in the control group the game training increased the MMN response more than the non-game training. In the dyslexia group, the MMN increase with the non-game training correlated with phonological awareness: the children with poorer phonological awareness showed a larger increase in the MMN response. Improved neural processing of foreign speech sounds as indicated by the MMN increase suggests that targeted training with a simple application could alleviate some spoken foreign-language learning difficulties that are related to phonological processing in children with dyslexia.

More efficient formation of longer-term representations for word forms at birth can be linked to better language skills at 2 years.

Infants are able to extract words from speech early in life. Here we show that the quality of forming longer-term representations for word forms at birth predicts expressive language ability at the age of two years. Seventy-five neonates were familiarized with two spoken disyllabic pseudowords. We then tested whether the neonate brain predicts the second syllable from the first one by presenting a familiarized pseudoword frequently, and occasionally violating the learned syllable combination by different rare pseudowords. Distinct brain responses were elicited by predicted and unpredicted word endings, suggesting that the neonates had learned the familiarized pseudowords. The difference between responses to predicted and unpredicted pseudowords indexing the quality of word-form learning during familiarization significantly correlated with expressive language scores (the mean length of utterance) at 24 months in the same infant. These findings suggest that 1) neonates can memorize disyllabic words so that a learned first syllable generates predictions for the word ending, and 2) early individual differences in the quality of word-form learning correlate with language skills. This relationship helps early identification of infants at risk for language impairment.

Gaming enhances learning-induced plastic changes in the brain.

Digital games may benefit children's learning, yet the factors that induce gaming benefits to cognition are not well known. In this study, we investigated the effectiveness of digital game-based learning in children by comparing the learning of foreign speech sounds and words in a digital game or a non-game digital application. To evaluate gaming-induced plastic changes in the brain, we used the mismatch negativity (MMN) brain response that reflects the access to long-term memory representations. We recorded auditory brain responses from 37 school-aged Finnish-speaking children before and after playing a computer-based language-learning game. The MMN amplitude increased between the pre- and post-measurement for the game condition but not for the non-game condition, suggesting that the gaming intervention enhanced learning more than the non-game intervention. The results indicate that digital games can be beneficial for children's speech-sound learning and that gaming elements per se, not just practice time, support learning.

Musical perceptual skills, but not neural auditory processing, are associated with better reading ability in childhood.

Musical activities have been suggested to be beneficial for language development in childhood. Randomised controlled trials using music have indicated that musical interventions can be used to support language skills in children with developmental language difficulties. However, it is not entirely clear how beneficial music activities are for normally developing children or how the effects mediated via music are transmitted. To investigate these questions, the present study used structural equation models to assess how musical training, perceptual musical skills, and auditory processing in the brain are associated with reading proficiency and each other. Perceptual musical skills were assessed using musicality tests while auditory processing in the brain was measured using mismatch negativity responses to pitch, duration, and phoneme length contrasts. Our participants were a community sample of 64 8-11-year-old typically developing children with and without musical training, recruited from four classes in four elementary schools in Finland. Approximately half of children had music as a hobby. Our results suggest that performance in tests of musical perceptual skills is directly linked with reading proficiency instead of being mediated via auditory processing in the brain. Auditory processing in the brain in itself seems not to be strongly linked with reading proficiency in these children. Our results support the view that musical perceptual skills are associated with reading skills regardless of musical training.

Discriminatory Brain Processes of Native and Foreign Language in Children with and without Reading Difficulties.

The association between impaired speech perception and reading difficulty has been well established in native language processing, as can be observed from brain activity. However, there has been scarce investigation of whether this association extends to brain activity during foreign language processing. The relationship between reading skills and neuronal speech representation of foreign language remains unclear. In the present study, we used event-related potentials (ERPs) with high-density EEG to investigate this question. Eleven- to 13-year-old children typically developed (CTR) or with reading difficulties (RD) were tested via a passive auditory oddball paradigm containing native (Finnish) and foreign (English) speech items. The change-detection-related ERP responses, the mismatch response (MMR), and the late discriminative negativity (LDN) were studied. The cluster-based permutation tests within and between groups were performed. The results showed an apparent language effect. In the CTR group, we found an atypical MMR in the foreign language processing and a larger LDN response for speech items containing a diphthong in both languages. In the RD group, we found unstable MMR with lower amplitude and a nonsignificant LDN response. A deficit in the LDN response in both languages was found within the RD group analysis. Moreover, we observed larger brain responses in the RD group and a hemispheric polarity reversal compared to the CTR group responses. Our results provide new evidence that language processing differed between the CTR and RD groups in early and late discriminatory responses and that language processing is linked to reading skills in both native and foreign language contexts.

Phonological Variations Are Compensated at the Lexical Level: Evidence From Auditory Neural Activity.

Dealing with phonological variations is important for speech processing. This article addresses whether phonological variations introduced by assimilatory processes are compensated for at the pre-lexical or lexical level, and whether the nature of variation and the phonological context influence this process. To this end, Swedish nasal regressive place assimilation was investigated using the mismatch negativity (MMN) component. In nasal regressive assimilation, the coronal nasal assimilates to the place of articulation of a following segment, most clearly with a velar or labial place of articulation, as in utan mej "without me" > [ʉːtam mɛjː]. In a passive auditory oddball paradigm, 15 Swedish speakers were presented with Swedish phrases with attested and unattested phonological variations and contexts for nasal assimilation. Attested variations - a coronal-to-labial change as in utan "without" > [ʉːtam] - were contrasted with unattested variations - a labial-to-coronal change as in utom "except" > ∗[ʉːtɔn] - in appropriate and inappropriate contexts created by mej "me" [mɛjː] and dej "you" [dɛjː]. Given that the MMN amplitude depends on the degree of variation between two stimuli, the MMN responses were expected to indicate to what extent the distance between variants was tolerated by the perceptual system. Since the MMN response reflects not only low-level acoustic processing but also higher-level linguistic processes, the results were predicted to indicate whether listeners process assimilation at the pre-lexical and lexical levels. The results indicated no significant interactions across variations, suggesting that variations in phonological forms do not incur any cost in lexical retrieval; hence such variation is compensated for at the lexical level. However, since the MMN response reached significance only for a labial-to-coronal change in a labial context and for a coronal-to-labial change in a coronal context, the compensation might have been influenced by the nature of variation and the phonological context. It is therefore concluded that while assimilation is compensated for at the lexical level, there is also some influence from pre-lexical processing. The present results reveal not only signal-based perception of phonological units, but also higher-level lexical processing, and are thus able to reconcile the bottom-up and top-down models of speech processing.

Intentional Training With Speech Production Supports Children's Learning the Meanings of Foreign Words: A Comparison of Four Learning Tasks.

To determine the best techniques to teach children foreign words, we compared the effectiveness of four different learning tasks on their foreign-word learning (i.e., learning word forms and word meanings). The tasks included incidental learning, intentional learning with production, intentional learning without production, and cross-situational statistical learning. We also analyzed whether children's age and cognitive skills correlate with the learning of word forms and word meanings. Forty-four 5-8-year-old children participated in the study. The results reveal that the children were able to learn the correct word forms from all four tasks and no differences emerged between the effectiveness of the tasks on the learning of word-forms. The children also learned the word meanings with all four tasks, yet the intentional task with production was more effective than the incidental task. This suggests that the ability of children to learn foreign words benefited from them knowing that they were supposed to learn new words and producing them aloud while training. The age of the children correlated with their learning results for word forms and meanings on the intentional task without production. The older children learned more effectively than the younger children in this task. Children's phonological processing skills were correlated with learning the word meanings from the incidental task, suggesting that children with better phonological skills were able to benefit from incidental learning more than children with poorer phonological skills. Altogether, the results suggest that children's foreign-language learning benefits from intentional training with speech production regardless of their age or cognitive skills.

Better Phonological Short-Term Memory Is Linked to Improved Cortical Memory Representations for Word Forms and Better Word Learning.

Language learning relies on both short-term and long-term memory. Phonological short-term memory (pSTM) is thought to play an important role in the learning of novel word forms. However, language learners may differ in their ability to maintain word representations in pSTM during interfering auditory input. We used magnetoencephalography (MEG) to investigate how pSTM capacity in better and poorer pSTM groups is linked to language learning and the maintenance of pseudowords in pSTM. In particular, MEG was recorded while participants maintained pseudowords in pSTM by covert speech rehearsal, and while these brain representations were probed by presenting auditory pseudowords with first or third syllables matching or mismatching the rehearsed item. A control condition included identical stimuli but no rehearsal. Differences in response strength between matching and mismatching syllables were interpreted as the phonological mapping negativity (PMN). While PMN for the first syllable was found in both groups, it was observed for the third syllable only in the group with better pSTM. This suggests that individuals with better pSTM maintained representations of trisyllabic pseudowords more accurately during interference than individuals with poorer pSTM. Importantly, the group with better pSTM learned words faster in a paired-associate word learning task, linking the PMN findings to language learning.

Rhythmic structure facilitates learning from auditory input in newborn infants.

Rhythm and metrical regularities are fundamental properties of music and poetry - and all of those are used in the interaction between infants and their parents. Music and rhythm perception have been shown to support auditory and language skills. Here we compare newborn infants' learning from a song, a nursery rhyme, and normal speech for the first time in the same study. Infants' electrophysiological brain responses revealed that the nursery rhyme condition facilitated learning from auditory input, and thus led to successful detection of deviations. These findings suggest that coincidence of prosodic cue patterns and to-be-learned items is more important than the format of the input. Overall, the present results support the view that rhythm is likely to create a template for future events, which allows auditory system to predict prospective input and thus facilitates language development.

Diminished brain responses to second-language words are linked with native-language literacy skills in dyslexia.

Dyslexia is characterized by poor reading skills, yet often also difficulties in second-language learning. The differences between native- and second-language speech processing and the establishment of new brain representations for spoken second language in dyslexia are not, however, well understood. We used recordings of the mismatch negativity component of event-related potential to determine possible differences between the activation of long-term memory representations for spoken native- and second-language word forms in Finnish-speaking 9-11-year-old children with or without dyslexia, studying English as their second language in school. In addition, we sought to investigate whether the bottleneck of dyslexic readers' second-language learning lies at the level of word representations or smaller units and whether the amplitude of mismatch negativity is correlated with native-language literacy and related skills. We found that the activation of brain representations for familiar second-language words, but not for second-language speech sounds or native-language words, was weaker in children with dyslexia than in typical readers. Source localization revealed that dyslexia was associated with weak activation of the right temporal cortex, which has been previously linked with word-form learning. Importantly, the amplitude of the mismatch negativity for familiar second-language words correlated with native-language literacy and rapid naming scores, suggesting a close link between second-language processing and these skills.

Predictive coding accelerates word recognition and learning in the early stages of language development.

The ability to predict future events in the environment and learn from them is a fundamental component of adaptive behavior across species. Here we propose that inferring predictions facilitates speech processing and word learning in the early stages of language development. Twelve- and 24-month olds' electrophysiological brain responses to heard syllables are faster and more robust when the preceding word context predicts the ending of a familiar word. For unfamiliar, novel word forms, however, word-expectancy violation generates a prediction error response, the strength of which significantly correlates with children's vocabulary scores at 12 months. These results suggest that predictive coding may accelerate word recognition and support early learning of novel words, including not only the learning of heard word forms but also their mapping to meanings. Prediction error may mediate learning via attention, since infants' attention allocation to the entire learning situation in natural environments could account for the link between prediction error and the understanding of word meanings. On the whole, the present results on predictive coding support the view that principles of brain function reported across domains in humans and non-human animals apply to language and its development in the infant brain. A video abstract of this article can be viewed at: http://hy.fi/unitube/video/e1cbb495-41d8-462e-8660-0864a1abd02c. [Correction added on 27 January 2017, after first online publication: The video abstract link was added.].

Predictive coding of phonological rules in auditory cortex: A mismatch negativity study.

The brain is constantly generating predictions of future sensory input to enable efficient adaptation. In the auditory domain, this applies also to the processing of speech. Here we aimed to determine whether the brain predicts the following segments of speech input on the basis of language-specific phonological rules that concern non-adjacent phonemes. Auditory event-related potentials (ERP) were recorded in a mismatch negativity (MMN) paradigm, where the Finnish vowel harmony, determined by the first syllables of pseudowords, either constrained or did not constrain the phonological composition of pseudoword endings. The phonological rule of vowel harmony was expected to create predictions about phonologically legal pseudoword endings. Results showed that MMN responses were larger for phonologically illegal than legal pseudowords, and P3a was elicited only for illegal pseudowords. This supports the hypothesis that speech input is evaluated against context-dependent phonological predictions that facilitate speech processing.

Neuroscience illuminating the influence of auditory or phonological intervention on language-related deficits.

Remediation programs for language-related learning deficits are urgently needed to enable equal opportunities in education. To meet this need, different training and intervention programs have been developed. Here we review, from an educational perspective, studies that have explored the neural basis of behavioral changes induced by auditory or phonological training in dyslexia, specific language impairment (SLI), and language-learning impairment (LLI). Training has been shown to induce plastic changes in deficient neural networks. In dyslexia, these include, most consistently, increased or normalized activation of previously hypoactive inferior frontal and occipito-temporal areas. In SLI and LLI, studies have shown the strengthening of previously weak auditory brain responses as a result of training. The combination of behavioral and brain measures of remedial gains has potential to increase the understanding of the causes of language-related deficits, which may help to target remedial interventions more accurately to the core problem.

Two distinct auditory-motor circuits for monitoring speech production as revealed by content-specific suppression of auditory cortex.

Speech production, both overt and covert, down-regulates the activation of auditory cortex. This is thought to be due to forward prediction of the sensory consequences of speech, contributing to a feedback control mechanism for speech production. Critically, however, these regulatory effects should be specific to speech content to enable accurate speech monitoring. To determine the extent to which such forward prediction is content-specific, we recorded the brain's neuromagnetic responses to heard multisyllabic pseudowords during covert rehearsal in working memory, contrasted with a control task. The cortical auditory processing of target syllables was significantly suppressed during rehearsal compared with control, but only when they matched the rehearsed items. This critical specificity to speech content enables accurate speech monitoring by forward prediction, as proposed by current models of speech production. The one-to-one phonological motor-to-auditory mappings also appear to serve the maintenance of information in phonological working memory. Further findings of right-hemispheric suppression in the case of whole-item matches and left-hemispheric enhancement for last-syllable mismatches suggest that speech production is monitored by 2 auditory-motor circuits operating on different timescales: Finer grain in the left versus coarser grain in the right hemisphere. Taken together, our findings provide hemisphere-specific evidence of the interface between inner and heard speech.

Computer game as a tool for training the identification of phonemic length.

Computer-assisted training of Finnish phonemic length was conducted with 7-year-old Russian-speaking second-language learners of Finnish. Phonemic length plays a different role in these two languages. The training included game activities with two- and three-syllable word and pseudo-word minimal pairs with prototypical vowel durations. The lowest accuracy scores were recorded for two-syllable words. Accuracy scores were higher for the minimal pairs with larger rather than smaller differences in duration. Accuracy scores were lower for long duration than for short duration. The ability to identify quantity degree was generalized to stimuli used in the identification test in two of the children. Ideas for improving the game are introduced.

Spatiotemporal Dynamics of the Processing of Spoken Inflected and Derived Words: A Combined EEG and MEG Study.

The spatiotemporal dynamics of the neural processing of spoken morphologically complex words are still an open issue. In the current study, we investigated the time course and neural sources of spoken inflected and derived words using simultaneously recorded electroencephalography (EEG) and magnetoencephalography (MEG) responses. Ten participants (native speakers) listened to inflected, derived, and monomorphemic Finnish words and judged their acceptability. EEG and MEG responses were time-locked to both the stimulus onset and the critical point (suffix onset for complex words, uniqueness point for monomorphemic words). The ERP results showed that inflected words elicited a larger left-lateralized negativity than derived and monomorphemic words approximately 200 ms after the critical point. Source modeling of MEG responses showed one bilateral source in the superior temporal area ∼100 ms after the critical point, with derived words eliciting stronger source amplitudes than inflected and monomorphemic words in the right hemisphere. Source modeling also showed two sources in the temporal cortex approximately 200 ms after the critical point. There, inflected words showed a more systematic pattern in source locations and elicited temporally distinct source activity in comparison to the derived word condition. The current results provide electrophysiological evidence for at least partially distinct cortical processing of spoken inflected and derived words. In general, the results support models of morphological processing stating that during the recognition of inflected words, the constituent morphemes are accessed separately. With regard to derived words, stem and suffix morphemes might be at least initially activated along with the whole word representation.