Speech disfluencies in typically developing Finnish-speaking children - preliminary results

We investigated the speech disfluencies of 54 typically fluent Finnish-speaking children: 14 children randomly selected from a longitudinal study (age levels 2, 3, and 4 years), and 40 children from a cross-sectional study (age levels 6, 7, 8, and 9 years). Speech samples, collected during a semi-structured conversation, were analysed for disfluencies per 100 words and 100 syllables. No significant within-age effect was found for the total frequency of disfluencies or disfluency types among the 2- to 4-year-olds. Across the 6- to 9-year-olds, between-group differences were found for the total frequency and type of disfluencies. Clinically relevant was that the criterion to distinguish normally fluent children from those who stutter, i.e., <3 stuttering-like disfluencies (SLD) per 100 syllables, was applicable in all age groups whereas the criterion <3SLD per 100 words was not. Consequently, these preliminary results suggest that different guidelines are needed for defining normal disfluency from stuttering in different languages

Effects of Recurrent Acute Otitis Media on Cortical Speech-Sound Processing in 2-Year Old Children

Objectives: To investigate at the age of 2 years the effects of childhood recurrent acute otitis media (RAOM) on central auditory processing by using cortical event-related potentials elicited by syllable stimuli. Design: During a 1-year period, 22- to 26-month-old children fulfilling the criteria for tympanostomy tube insertion in Oulu University Hospital, Oulu, Finland, were recruited to the RAOM group (N = 20). The control group (N = 19) was matched by age, sex, and mother&rsquo;s educational level. In both groups, children were typically developing and had no family history of language disorder or developmental language problems. Finnish syllables /ke:/ and /pi:/ as standards and their variants with changes in frequency, intensity, vowel, consonant, and vowel duration as deviants were used to record P1, N2, and mismatch negativity (MMN) responses in the multifeature paradigm. The clinically healthy ears at the time of registration were a prerequisite for the participation. Results: Children with RAOM and their controls showed the age-typical P1 and N2 responses with no differences in the amplitudes or latencies between the groups, which suggests unaffected basic encoding of sound features and sound representation formation. However, the groups showed different auditory discrimination profiles. In children with RAOM, frequency and vowel MMN amplitudes were increased. Furthermore, the MMN latency for the frequency change was shorter and the frequency MMN amplitude lateralized to the left hemisphere in the RAOM group instead of an adult-like right-hemispheric lateralization observed in the controls. The children with RAOM had a more anterior MMN amplitude scalp distribution for the intensity change than control children. In addition, the MMN amplitude elicited by consonant change was evenly distributed unlike in controls, who had a left-side preponderant lateralization. Taken together, these results suggest an elevated responsiveness for frequency, vowel, and intensity changes, and an immature pattern of discriminating small speech sound contrasts in children with RAOM. Conclusions: The results suggest that childhood RAOM does not affect the central auditory pathway integrity or sound encoding. However, RAOM may lead to aberrant preattentive discrimination of sound features even when the peripheral auditory input is normal. These results are clinically significant because even transient problems with auditory processing may delay language development.</div

Atypical perceptual narrowing in prematurely born infants is associated with compromised language acquisition at 2 years of age

Background: Early auditory experiences are a prerequisite for speech and language acquisition. In healthy children, phoneme discrimination abilities improve for native and degrade for unfamiliar, socially irrelevant phoneme contrasts between 6 and 12 months of age as the brain tunes itself to, and specializes in the native spoken language. This process is known as perceptual narrowing, and has been found to predict normal native language acquisition. Prematurely born infants are known to be at an elevated risk for later language problems, but it remains unclear whether these problems relate to early perceptual narrowing. To address this question, we investigated early neurophysiological phoneme discrimination abilities and later language skills in prematurely born infants and in healthy, full-term infants. Results: Our follow-up study shows for the first time that perceptual narrowing for non-native phoneme contrasts found in the healthy controls at 12 months was not observed in very prematurely born infants. An electric mismatch response of the brain indicated that whereas full-term infants gradually lost their ability to discriminate non-native phonemes from 6 to 12 months of age, prematurely born infants kept on this ability. Language performance tested at the age of 2 years showed a significant delay in the prematurely born group. Moreover, those infants who did not become specialized in native phonemes at the age of one year, performed worse in the communicative language test (MacArthur Communicative Development Inventories) at the age of two years. Thus, decline in sensitivity to non-native phonemes served as a predictor for further language development. Conclusion: Our data suggest that detrimental effects of prematurity on language skills are based on the low degree of specialization to native language early in development. Moreover, delayed or atypical perceptual narrowing was associated with slower language acquisition. The results hence suggest that language problems related to prematurity may partially originate already from this early tuning stage of language acquisition

Subjective face recognition difficulties, aberrant sensibility, sleeping disturbances and aberrant eating habits in families with Asperger syndrome

BACKGROUND: The present study was undertaken in order to determine whether a set of clinical features, which are not included in the DSM-IV or ICD-10 for Asperger Syndrome (AS), are associated with AS in particular or whether they are merely a familial trait that is not related to the diagnosis. METHODS: Ten large families, a total of 138 persons, of whom 58 individuals fulfilled the diagnostic criteria for AS and another 56 did not to fulfill these criteria, were studied using a structured interview focusing on the possible presence of face recognition difficulties, aberrant sensibility and eating habits and sleeping disturbances. RESULTS: The prevalence for face recognition difficulties was 46.6% in individuals with AS compared with 10.7% in the control group. The corresponding figures for subjectively reported presence of aberrant sensibilities were 91.4% and 46.6%, for sleeping disturbances 48.3% and 23.2% and for aberrant eating habits 60.3% and 14.3%, respectively. CONCLUSION: An aberrant processing of sensory information appears to be a common feature in AS. The impact of these and other clinical features that are not incorporated in the ICD-10 and DSM-IV on our understanding of AS may hitherto have been underestimated. These associated clinical traits may well be reflected by the behavioural characteristics of these individuals

Differentiation of Schizophrenia Patients from Healthy Subjects by Mismatch Negativity and Neuropsychological Tests

BACKGROUND: Schizophrenia is a heterogeneous disorder with diverse presentations. The current and the proposed DSM-V diagnostic system remains phenomenologically based, despite the fact that several neurobiological and neuropsychological markers have been identified. A multivariate approach has better diagnostic utility than a single marker method. In this study, the mismatch negativity (MMN) deficit of schizophrenia was first replicated in a Han Chinese population, and then the MMN was combined with several neuropsychological measurements to differentiate schizophrenia patients from healthy subjects. METHODOLOGY/PRINCIPAL FINDINGS: 120 schizophrenia patients and 76 healthy controls were recruited. Each subject received examinations for duration MMN, Continuous Performance Test, Wisconsin Card Sorting Test, and Wechsler Adult Intelligence Scale Third Edition (WAIS-III). The MMN was compared between cases and controls, and important covariates were investigated. Schizophrenia patients had significantly reduced MMN amplitudes, and MMN decreased with increasing age in both patient and control groups. None of the neuropsychological indices correlated with MMN. Predictive multivariate logistic regression models using the MMN and neuropsychological measurements as predictors were developed. Four predictors, including MMN at electrode FCz and three scores from the WAIS-III (Arithmetic, Block Design, and Performance IQ) were retained in the final predictive model. The model performed well in differentiating patients from healthy subjects (percentage of concordant pairs: 90.5%). CONCLUSIONS/SIGNIFICANCE: MMN deficits were found in Han Chinese schizophrenia patients. The multivariate approach combining biomarkers from different modalities such as electrophysiology and neuropsychology had a better diagnostic utility

Auditory event-related potentials as indices of language impairment in children born preterm and with Asperger syndrome

Abstract The main objective of the present follow-up study was to investigate auditory processing by using auditory event related potentials (ERPs), and language development to determine whether a correlation exists between auditory ERPs and language development. Auditory processing was investigated in very low birth weight (VLBW) preterm children and matched controls at mean ages of 4 and 6 years to determine whether there are differences in ERPs between VLBW preterm children and controls. Language development was measured at the mean ages of 2, 4 and 6 years to investigate the developmental course of language learning and to determine whether a relationship exists between ERPs, especially mismatch negativity (MMN), and language development. Auditory ERPs were also measured in children with AS (mean age 9;1 years) and matched controls to assess whether differences can be found between these two groups of children. Language development in children with AS was not investigated for this study. VLBW preterm children exhibited difficulties in the auditory processing at the level of obligatory ERPs, MMN, late MMN (lMMN) and behavioural tests. Both language comprehension and production were deficient in the preterm group compared to their controls. Lexical development was the most prominent phenomenon differentiating preterm children from their controls. MMN and lMMN amplitudes were attenuated most in children with naming difficulty at the ages of 4 and 6 years. Weak or totally missing MMN at the age of 4 years was mainly found in children with naming difficulties. Children with AS also displayed abnormalities in auditory processing, as indexed by delayed MMN latency. MMN was most delayed in the right hemisphere and specifically for tones. In conclusion: VLBW preterm children and children with AS exhibited difficulties in auditory processing. MMN correlated well with language development in preterm children. Therefore, auditory ERPs, especially MMN, should be used in combination with language measures to identify the children at a risk for deficient auditory processing and language delays

Decreased occipital alpha oscillation in children who stutter during a visual Go/Nogo task

Abstract Objective: Our goal was to discover attention- and inhibitory control-related differences in the main oscillations of the brain of children who stutter (CWS) compared to typically developed children (TDC). Methods: We performed a time-frequency analysis using wavelets, fast Fourier transformation (FFT) and the Alpha/Theta power ratio of EEG data collected during a visual Go/Nogo task in 7–9 year old CWS and TDC, including also the time window between consecutive tasks. Results: CWS showed significantly reduced occipital alpha power and Alpha/Theta ratio in the “resting” or preparatory period between visual stimuli especially in the Nogo condition. Conclusions: The CWS demonstrate reduced inhibition of the visual cortex and information processing in the absence of visual stimuli, which may be related to problems in attentional gating. Significance: Occipital alpha oscillation is elementary in the control and inhibition of visual attention and the lack of occipital alpha modulation indicate fundamental differences in the regulation of visual information processing in CWS. Our findings support the view of stuttering as part of a wide-ranging brain dysfunction most likely involving also attentional and inhibitory networks