Language dysfunction in children with Rolandic epilepsy

Rolandic epilepsy is regarded as the classic example of benign focal epilepsy. However, neuropsychological deficits have been noted in affected children. As Rolandic discharges are mainly distributed over the centrotemporal region, specific interference with language function might be suspected. Therefore, we conducted a standardized neuropsychological assessment in children with Rolandic epilepsy which covered all important aspects of language processing. We measured intelligence Quotient, verbal memory, auditory discrimination, vocabulary, grammar and literacy in 20 children with an active Rolandic focus. Information about performance at school was obtained from teachers by means of a questionnaire. Patients with Rolandic epilepsy failed five of the twelve standardized language tests significantly more often than the normative population and consequently showed impairment of the following functions: reading, spelling, auditory verbal learning, auditory discrimination with background noise and expressive grammar. Thirteen of the 20 children showed language dysfunction with difficulties in two or more of the twelve standardized language tests. In eight of these 13 children the Full Scale Intelligence Quotient was within average range, indicating a specific language deficit. Language dysfunction was closely associated with learning difficulties at school. This study documents a consistent pattern of language dysfunction in children with Rolandic epilepsy which suggests interictal dysfunction of perisylvian language areas.     

Sensitivity to dynamic auditory and visual stimuli predicts nonword reading ability in both dyslexic and normal readers

BACKGROUND: Developmental dyslexia is a specific disorder of reading and spelling that affects 3-9% of school-age children and adults. Contrary to the view that it results solely from deficits in processes specific to linguistic analysis, current research has shown that deficits in more basic auditory or visual skills may contribute to the reading difficulties of dyslexic individuals. These might also have a crucial role in the development of normal reading skills. Evidence for visual deficits in dyslexia is usually found only with dynamic and not static stimuli, implicating the magnocellular pathway or dorsal visual stream as the cellular locus responsible. Studies of such a dissociation between the processing of dynamic and static auditory stimuli have not been reported previously. RESULTS: We show that dyslexic individuals are less sensitive both to particular rates of auditory frequency modulation (2 Hz and 40 Hz but not 240 Hz) and to dynamic visual-motion stimuli. There were high correlations, for both dyslexic and normal readers, between their sensitivity to the dynamic auditory and visual stimuli. Nonword reading, a measure of phonological awareness believed crucial to reading development, was also found to be related to these sensory measures. CONCLUSIONS: These results further implicate neuronal mechanisms that are specialised for detecting stimulus timing and change as being dysfunctional in many dyslexic individuals. The dissociation observed in the performance of dyslexic individuals on different auditory tasks suggests a sub-modality division similar to that already described in the visual system. These dynamic tests may provide a non-linguistic means of identifying children at risk of reading failure.     

A dyspraxic deficit in specific language impairment and developmental coordination disorder? Evidence from hand and arm movements

The extent to which children with either specific language impairment (SLI) or developmental coordination disorder (DCD) could be considered dyspraxic was examined using three tasks involving either familiar, or unfamiliar actions. SLI is diagnosed in children who fail to develop language in the normal fashion for no apparent reason, while the DCD diagnosis is applied to a child who experiences problems with movement in the absence of other difficulties. Seventy-two children aged between 5 and 13 years participated, falling into one of four groups: (1) children with specific language impairment (SLI), (2) children with developmental coordination disorder (DCD), (3) age-matched control children, and (4) younger control children. The performance of the clinical groups resembled that of younger normally developing children. Children with SLI, DCD, and the younger controls showed significant difficulty on the task requiring the production of familiar, but not unfamiliar postures. The deficit observed in the SLI group is particularly striking because it was seen both in those with and those without recognized motor difficulties.     

Auditory lexical decisions of children with specific language impairment

To determine whether children with specific language impairment (SLI) take longer than age peers to recognize sequences of sounds that represent words in their lexicon, we compared auditory lexical decision times of children with SLI to those of typically developing age peers. Children with SLI were significantly slower than peers, but speed of word recognition was not correlated with measures of language comprehension for children with SLI. Furthermore, time to detect an auditory signal and initiate a vocal response did not account for the differences between groups. Possible interpretations of the results are discussed with two explanations-differences between groups in task-related factors that stressed processing capacity or in the nature of phonetic/phonological representations-seeming more likely than others.     

The use of nonword repetition as a test of phonological memory in children with Down syndrome

Recent research suggests a significant relationship between verbal short-term memory and normal language development. Although poor short-term memory and impaired language are features of Down syndrome there has been little investigation of the relationship between these functions in this population, and no studies have included the nonword repetition test devised by Gathercole and Baddeley on which much of the evidence from normal development is based. This study reports the use of nonword repetition with 33 children and teenagers with Down syndrome aged from 5 to 18 years, and investigates the relationship between this test and other memory and language measures. Word repetition was included as an indirect control for the perceptual and speech impairments often associated with this group. Words were repeated significantly more successfully than nonwords and both these tasks were sensitive to word length. Nonword repetition was significantly correlated with age, and when age and nonverbal cognitive ability were controlled, nonword repetition was significantly correlated with all other language-based memory measures, i.e. auditory digit span, word span, sentence repetition, and fluency, and also with memory for a sequence of hand movements, but not with memory for faces or a visual digit span task. There was also a significant relationship between nonword repetition and receptive vocabulary, language comprehension, and reading. When performance on the word repetition task was controlled in addition to age and nonverbal ability, significant correlations between nonword repetition and word span, sentence memory, hand movements, language comprehension, and reading remained. Fewer relationships between auditory digit span and these other measures were established; in particular, there was no association between digit span and the language and reading measures. Results suggest that nonword repetition is a reliable measure of phonological memory in Down syndrome and can predict language comprehension and reading ability.     

Review of Language impairment and psychopathology in infants, children, and adolescents.

Reviews the book, Language impairment and psychopathology in infants, children, and adolescents by Nancy J. Cohen (see record 2001-05782-000). Approximately half of the children referred to mental health clinics for social-emotional problems have, on testing, been shown to have co-occurring language impairment. Conversely, about the same percentage of children originally seen for difficulties with language are later diagnosed with social-emotional problems. It is this overlap that Nancy Cohen explores in this concise and immensely readable book. We view this book as a broad and integrative first step that ought to be followed with more depth in specific areas. Thus, although much remains to be done, this book provides an excellent overview of a complex literature and will encourage interesting new clinical and research endeavours. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Kindergarten Prediction of Reading Skills: A Longitudinal Comparative Analysis.

There is considerable focus in public policy on screening children for reading difficulties. Sixty years of research have not resolved questions of what constructs assessed in kindergarten best predict subsequent reading outcomes. This study assessed the relative importance of multiple measures obtained in a kindergarten sample for the prediction of reading outcomes at the end of 1st and 2nd grades. Analyses revealed that measures of phonological awareness, letter sound knowledge, and naming speed consistently accounted for the unique variance across reading outcomes whereas measures of perceptual skills and oral language and vocabulary did not. These results show that measures of letter name and letter sound knowledge, naming speed, and phonological awareness are good predictors of multiple reading outcomes in Grades 1 and 2. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Development of grammatical-sensitivity, phonological, and short-term memory skills in normally achieving and learning disabled children.

The development of a variety of grammatical-sensitivity and phonological skills was studied in 138 normally achieving, 65 reading-disabled, 63 arithmetic-disabled, and 15 attention deficit disordered (hyperactive) children 7 to 14 years old. Word recognition and phonics skills were highly related, and reading comprehension and phonics skills were less so. Grammatical sensitivity and short-term memory were significantly correlated with a variety of reading skills. Children with a reading disability showed a significant lag in the development of grammatical sensitivity and short-term memory and an even greater deficit in phonological skills. The children with a specific arithmetic disability had adequate grammatical abilities, but below-average memory skills at all ages. Children with an attention deficit but normal achievement scores did not have any major difficulties except on a reading-comprehension task that appears to have significant memory and attention components. The acquisition of reading skills is closely related to the development of grammatical and phonological skills, and deficiencies in these areas are related to difficulties with the acquisition of written language skills. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Evidence for a grammar-specific deficit in children

BACKGROUND: Specific language impairment (SLI) is a disorder in which language acquisition is impaired in an otherwise normally developing child. SLI affects around 7% of children. The existence of a purely grammatical form of SLI has become extremely controversial because it points to the existence and innateness of a putative grammatical subsystem in the brain. Some researchers dispute the existence of a purely grammatical form of SLI. They hypothesise that SLI in children is caused by deficits in auditory and/or general cognitive processing, or social factors. There are also claims that the cognitive abilities of people with SLI have not yet been sufficiently characterised to substantiate the existence of SLI in a pure grammatical form. RESULTS: We present a case study of a boy, known as AZ, with SLI. To investigate the claim for a primary grammatical impairment, we distinguish between grammatical abilities, non-grammatical language abilities and non-verbal cognitive abilities. We investigated AZ's abilities in each of these areas. AZ performed normally on auditory and cognitive tasks, yet exhibited severe grammatical impairments. This is evidence for a developmental grammatical deficit that cannot be explained as a by-product of retardation or auditory difficulties. CONCLUSIONS: The case of AZ provides evidence supporting the existence of a genetically determined, specialised mechanism that is necessary for the normal development of human language.     

Using mismatch negativity to study central auditory processing in developmental language and literacy impairments: Where are we, and where should we be going?

A popular theoretical account of developmental language and literacy disorders implicates poor auditory temporal processing in their etiology, but evidence from studies using behavioral measures has yielded inconsistent results. The mismatch negativity (MMN) component of the auditory event-related potential has been recommended as an alternative, relatively objective, measure of the brain's ability to discriminate sounds that is suitable for children with limited attention or motivation. A literature search revealed 26 studies of the MMN in individuals with dyslexia or specific language impairment and 4 studies of infants or children at familial risk of these disorders. Findings were highly inconsistent. Overall, attenuation of the MMN and atypical lateralization in the clinical group were most likely to be found in studies using rapidly presented stimuli, including nonverbal sounds. The MMN literature offers tentative support for the hypothesis that auditory temporal processing is impaired in language and literacy disorders, but the field is plagued by methodological inconsistencies, low reliability of measures, and low statistical power. The article concludes with recommendations for improving this state of affairs. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Executive function in children with Tourette syndrome and/or attention deficit hyperactivity disorder

Tourette Syndrome (TS) in children is associated with various neurobehavioral disorders including attention deficit hyperactivity disorder (ADHD). Children with TS and ADHD show some difficulties with neuropsychological tasks, but we do not know if children with TS alone have neuropsychological deficits. To assess specific cognitive differences among children with TS and/or ADHD, we administered a battery of neuropsychological tests, including 10 tasks related to executive function (EF), to 10 children with TS-only, 48 with ADHD-only, and 32 with TS + ADHD. Children in all groups could not efficiently produce output on a timed continuous performance task [Test of Variables of Attention (TOVA) mean reaction time and reaction time variability]. Children with TS-only appeared to have fewer EF impairments and significantly higher perceptual organization scores than children with TS + ADHD or ADHD-only. These findings suggest that deficiencies in choice reaction time and consistency of timed responses are common to all three groups, but children with TS-only have relatively less EF impairment than children with TS + ADHD or ADHD-only.     

Performance across different areas of mathematical cognition in children with learning difficulties.

The performance of 210 2nd graders in different areas of mathematical cognition was examined. Children were divided into 4 achievement groups: children with difficulties in mathematics but not in reading (MD-only), children with difficulties in both mathematics and reading (MD/RD), children with difficulties in reading but not in mathematics, and children with normal achievement. Although both MD groups performed worse than normally achieving groups in most areas of mathematical cognition, the MD-only group showed an advantage over the MD/RD group in exact calculation of arithmetic combinations and in problem solving. The 2 groups did not differ in approximate arithmetic and understanding of place value and written computation. Children with MD-only seem to be superior to children with MD/RD in areas that may be mediated by language but not in ones that rely on numerical magnitudes, visuospatial processing, and automaticity. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Children's imitations of intonation contours: are rising tones more difficult than falling tones?

Perceptual evidence suggests that young children do not imitate adult-modeled intonation patterns with a rising pitch contour (rising tones) as well as those with a falling pitch contour (falling tones). To investigate the acoustic basis of this uneven imitation pattern, 10 4-year-old children were asked to imitate short sentences with falling and rising tones in 4 sentence contexts called "intonation groups." The results indicated that the children used more falling tones than adults in most intonation groups. When the children matched the adult-modeled contour direction (falling or rising), the children's speed of pitch change was comparable to that of adults in the falling tones of final intonation groups and in the rising tones of nonfinal groups, but was slower than that of adults in the complementary environments. In a manner consistent with previously reported perceptual data, the instrumental findings indicate that rising tones may be more difficult for 4-year-old children to produce than falling tones. The results additionally suggest that children's intonation is sensitive not only to the direction of tonal contours but also to their position in sentence-final versus nonfinal intonation groups.     

Cognitive arithmetic and problem solving: a comparison of children with specific and general mathematics difficulties

This study examined problem-solving and number-fact skills in two subgroups of third-grade children with mathematics difficulties (MD): MD-specific (n = 12) and MD-general (n = 12). The MD-specific group had difficulties in mathematics but not in reading, and the MD-general group had difficulties in reading as well as in mathematics. A comparison group of nonimpaired children (n = 24) also was included. The findings showed that on both story and number-fact problems, the MD-specific group performed worse than the nonimpaired group in timed conditions but not in untimed conditions. The MD-general group, on the other hand, performed worse than the nonimpaired group, regardless of whether tasks were timed or not. An analysis of children's strategies in untimed conditions showed that both the MD-specific and the MD-general groups relied more on backup strategies than the nonimpaired group. However, children in the MD-specific group executed backup strategies more skillfully than children in the MD-general group, allowing them to achieve parity with children in the nonimpaired group when tasks were not timed. The findings suggest that children with specific MD have circumscribed deficits associated with fact retrieval, whereas children with general MD have more basic delays associated with problem conceptualization and execution of calculation procedures.     

Sequential stream segregation in the absence of spectral cues

This paper investigates the cues used by the auditory system in the perceptual organization of sequential sounds. In particular, the ability to organize sounds in the absence of spectral cues is studied. In the first experiment listeners were presented with a tone sequence ABA ABA ..., where the fundamental frequency (f0) of tone A was fixed at 100 Hz and the f0 difference between tones A and B varied across trials between 1 and 11 semitones. Three spectral conditions were tested: pure tones, harmonic complexes filtered with a bandpass region between 500 and 2000 Hz, and harmonic complexes filtered with a bandpass region chosen so that only harmonics above the tenth would be passed by the filter, thus severely limiting spectral information. Listeners generally reported that they could segregate tones A and B into two separate perceptual streams when the f0 interval exceeded about four semitones. This was true for all conditions. The second experiment showed that most listeners were better able to recognize a short atonal melody interleaved with random distracting tones when the distracting tones were in an f0 region 11 semitones higher than the melody than when the distracting tones were in the same f0 region. The results were similar for both pure tones and complex tones comprising only high, unresolved harmonics. The results from both experiments show that spectral separation is not a necessary condition for perceptual stream segregation. This suggests that models of stream segregation that are based solely on spectral properties may require some revision.     

Auditory stream segregation and the perception of across-frequency synchrony.

This study explored the extent to which sequential auditory grouping affects the perception of temporal synchrony. In Experiment 1, listeners discriminated between 2 pairs of asynchronous “target” tones at different frequencies, A and B, in which the B tone either led or lagged. Thresholds were markedly higher when the target tones were temporally surrounded by “captor tones” at the A frequency than when the captor tones were absent or at a remote frequency. Experiment 2 extended these findings to asynchrony detection, revealing that the perception of synchrony, one of the most potent cues for simultaneous auditory grouping, is not immune to competing effects of sequential grouping. Experiment 3 examined the influence of ear separation on the interactions between sequential and simultaneous grouping cues. The results showed that, although ear separation could facilitate perceptual segregation and impair asynchrony detection, it did not prevent the perceptual integration of simultaneous sounds. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Information processing by school-age children with specific language impairment: evidence from a modality effect paradigm

School-age children with specific language impairment (SLI) and age-matched controls were tested for immediate recall of digits presented visually, auditorily, or audiovisually. Recall tasks compared speaking and pointing response modalities. Each participant was tested at a level that was consistent with her or his auditory short-term memory span. Traditional effects of primacy, recency, and modality (an auditory recall advantage) were obtained for both groups. The groups performed similarly when audiovisual stimuli were paired with a spoken response, but children with SLI had smaller recency effects together with an unusually poor recall when visually presented items were paired with a pointing response. Such results cannot be explained on the basis of an auditory or speech deficit per se, and suggest that children with SLI have difficulty either retaining or using phonological codes, or both, during tasks that require multiple mental operations. Capacity limitations, involving the rapid decay of phonological representations and/or performance limitations related to the use of less demanding and less effective coding and retrieval strategies, could have contributed to the working memory deficiencies in the children with SLI.     

Differences in begging behaviour between barn swallow, Hirundo rustica, nestlings

Studies comparing children's and adults' labeling of speech stimuli have repeatedly shown that children's phonological decisions are more strongly related to portions of the signal that involve rapid spectral change (i.e., formant transitions) and less related to other signal components than are adults' decisions. Such findings have led to a model termed the Developmental Weighting Shift, which suggests that children initially assign particularly strong weight to formant transitions to help delimit individual words in the continuous speech stream but gradually modify these strategies to be more like those of adults as they learn about word-internal structure. The goal of the current study was to test a reasonable alternative: that these apparent age-related differences in perceptual weighting strategies for speech are instead due to age-related differences in auditory sensitivity. To this end, difference limens (DLs) were obtained from children (ages 5 and 7 years) and adults for three types of acoustic properties: dynamic-spectral, static-spectral, and temporal. Two testable hypotheses were offered: Labeling results could reflect either absolute differences in sensitivity between children and adults or relative differences in sensitivity within each group. Empirical support for either hypothesis would indicate that apparent developmental changes in perceptual weighting strategies are actually due to developmental changes in auditory sensitivity to acoustic properties. Results of this study contradicted predictions of both hypotheses, sustaining the suggestion that children's perceptual weighting strategies for speech-relevant acoustic properties change as they gain experience with a native language.     

Impulsiveness and impulse control. On the psychological and psychopathological conceptualization

Facets of reading and language were examined in 131 9- to 12-year-old children for whom prenatal exposure to marijuana and cigarettes had been ascertained. The subjects were from a low-risk, predominantly middle class sample who are participants in an ongoing longitudinal study. Discriminant Function Analysis revealed a dose-dependent association that remained after controlling for potential confounds, between prenatal cigarette exposure and lower language and lower reading scores, particularly on auditory-related aspects of this latter measure. The findings are interpreted as consistent with earlier observations of an association between cigarette smoking during pregnancy and altered auditory functioning in the offspring. Similarities and differences between the reading observations and dyslexia are discussed. Maternal prenatal passive smoke exposure did not appear to contribute to either the language or reading outcomes at this age but postnatal secondhand smoke exposure by the child was associated with poorer language scores. Prenatal marijuana exposure was not significantly related to either the reading or language outcomes.     

Mechanisms of perceptual organization and auditory selective attention: The role of pattern structure.

Five experiments were conducted to determine whether unpracticed listeners shift auditory attention in an anticipatory fashion in accordance with the Frequency?×?Time structure of a rapid sequence of tones. Listeners were presented on each trial with a series of pure tones either ascending or descending in frequency in a predictable manner. In all experiments, judgments were made more quickly and accurately for targets that were inconsistent with pattern structure. Performance was shown to depend on the magnitude of the frequency violation, with better performance for larger violations. Further, the strength of this effect was attenuated when overall pattern predictability was reduced. These results suggest strongly that unpracticed listeners do not automatically allocate attention in accordance with pattern structure. Rather, it appears that a preattentive perceptual process acts to integrate information likely to have arisen from the same source and that this early perceptual processing imposes constraints on selection. (PsycINFO Database Record (c) 2010 APA, all rights reserved)