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This study attempted to quantify diagnostic characteristics related to consonant production of developmental verbal dyspraxia (DVD) in 11 Dutch children (ages 6 and 7). The study was able to quantify diagnostic characteristics but found very few qualitative differences in error patterns between children with DVD and 11 age-matched children with normal speech. (Author/DB)

Three noninvasive Maximum Performance Tasks (MPT) - Maximum Sound Prolongation (MSP), Fundamental Frequency Range (FFR), and Maximum Repetition Rate (MRR) - were administered to 11 children with spastic dysarthria due to cerebral palsy and to 11 control children with normal speech in order to determine the value of the tasks for differentiating between these groups of children. From the acoustic measurements, nine parameters were calculated, and in seven of them highly significant group differences were found. By adding the unweighted z-scores of four parameters (maximum sound prolongation, syllable duration, fundamental frequency range, inter-utterance variability of syllable duration), a composite z-score was constructed with nonoverlapping distributions for both groups. The authors conclude that maximum performance tasks, despite the large intrasubject and intersubject variability in both normal and pathological speakers, are powerful tools for detecting spastic dysarthria.

Heathlands in Western Europe have shown dramatic declines over the last century and therefore have been given a high conservation priority in the Habitats Directive of the European Union (EU). Accurate surveying and monitoring of heathland habitats is essential for appropriate conservation management, but the large heterogeneity of vegetation types within habitats as well as the occurrence of similar vegetation across habitat types hinders a straightforward, automated mapping based on aerial images. In such a case, a context-dependent classification algorithm is expected to be superior to traditional classification techniques. This article presents a novel approach to map the conservation status of heathland vegetation by using a hierarchical classification scheme that describes the structural dependencies in the field between the basic vegetation and the land-cover types that habitats are composed of. These dependency relationships are included as contextual information in the classification process, using a tree-structured Markov random field (TS-MRF) technique with a tree that reflects the hierarchy of the classification scheme. Results of this approach for a heathland area in Belgium were compared with results from more conventional classification approaches. Validation of the results showed that the structure of the scheme contained important spatial relationships, which were further reinforced by using the contextual classification strategy, especially for the most detailed level of the classification scheme. Accuracy increased and the classification results were more suitable for visual interpretation. [ABSTRACT FROM AUTHOR]

In a previous study a diagnostic procedure was developed to assess motoric involvement in clear cases of developmental apraxia of speech (DAS) and spastic dysarthria, as well as normal-speaking children. The aim of the present study is to cross-validate this diagnostic procedure. To achieve this aim the maximum performance tasks of the protocol, consisting of maximum vowel and fricative prolongation, and maximum syllable repetition, were administered to less clear cases of DAS and spastic dysarthria, children with a speech disorder of unknown origin and newly selected normal-speaking children (total number of children in the study, 72; aged predominantly between 4 and 12 years). The results showed that spastic dysarthria can be diagnosed on the basis of the maximum rate of repetitive sequences ('papa ...', 'tata ...', 'kaka ...') in combination with maximum vowel prolongation. DAS can be diagnosed on the basis of the maximum rate of alternating sequences ('pataka . . .') in combination with maximum fricative prolongation. Using the diagnosis of speech-language pathologists as a criterion, sensitivity and specificity values were obtained ranging from 89 to 100%. Among the children with a speech disorder of unknown origin significant dysarthric or apraxic involvement was observed. Thus, it can be concluded that the diagnostic procedure yields quantitative measures of the degree to which dysarthria or apraxia plays a role in the development and maintenance of speech disorders in children. [ABSTRACT FROM AUTHOR]

Of the triad of symptoms found in autism spectrum disorder (ASD), that is, social impairments, communication difficulties and repetitive interests and behaviour, the social impairments are the most stable and common throughout the lifespan. They typically manifest themselves in abnormalities as reciprocal interactions and difficulties in the expression and recognition of emotions. Although peer interactions become especially important during adolescence, little is known about the mentalizing abilities of high-functioning adolescents with ASD. Here, we compared the mentalizing skills and emotion recognition abilities of 21 high-functioning adolescents with ASD and 21 matched controls. All adolescents had estimated above-average verbal intelligence levels. Spontaneous social abilities and task-related social abilities were measured using questionnaires, tasks and the Autism Diagnostic Observation Schedule. Results confirm social impairment in daily life situations in adolescents with ASD, but were not found on experimental tasks of social cognition. The use of more explicit cognitive or verbally mediating reasoning techniques and a lesser tendency of high-functioning adolescents with ASD to search for and use social information in natural environments are further discussed.

Aim: People with autism spectrum disorder (ASD) typically have deficits in the working memory (WM) system. WM is found to be an essential chain in successfully navigating in the social world. We hypothesize that brain networks for WM have an altered network integrity in ASD compared to controls., Methods: Thirteen adolescents (one female) with autistic disorder (n = 1), Asperger's disorder (n = 7), or pervasive developmental disorder not otherwise specified (n = 5), and 13 typically developing healthy control adolescents (one female) participated in this study. Functional magnetic resonance imaging (MRI) was performed using an n-back task and in resting state., Results: The analysis of the behavioral data revealed deficits in WM performance in ASD, but only when tested to the limit. Adolescents with ASD showed lower binary global efficiency in the WM network than the healthy control group with n-back and resting-state data. This correlated with diagnostic scores for total problems, reciprocity, and language., Conclusion: Adolescents with higher-functioning autism have difficulty with the WM system, which is typically compensated. Functional MRI markers of brain network organization in ASD are related to characteristics of autism as represented in diagnostic scores. Therefore, functional MRI provides neuronal correlates for memory difficulties in adolescents with ASD., (© 2017 The Authors. Psychiatry and Clinical Neurosciences published by John Wiley & Sons Australia, Ltd on behalf of Japanese Society of Psychiatry and Neurology.)

Previous studies have suggested that alterations in excitatory/inhibitory neurotransmitters might play a crucial role in autism spectrum disorder (ASD). Proton magnetic resonance spectroscopy ( 1 H-MRS) can provide valuable information about abnormal brain metabolism and neurotransmitter concentrations. However, few 1 H-MRS studies have been published on the imbalance of the two most abundant neurotransmitters in ASD: glutamate (Glu) and gamma-aminobutyric acid (GABA). Moreover, to our knowledge none of these published studies is performed with a study population consisting purely of high-functioning autism (HFA) adolescents. Selecting only individuals with HFA eliminates factors possibly related to intellectual impairment instead of ASD. This study aims to assess Glu and GABA neurotransmitter concentrations in HFA. Occipital concentrations of Glu and GABA plus macromolecules (GABA+) were obtained using 1 H-MRS relative to creatine (Cr) in adolescents with HFA (n=15 and n=13 respectively) and a healthy control group (n=17). Multiple linear regression revealed significantly higher Glu/Cr and lower GABA+/Glu concentrations in the HFA group compared to the controls. These results imply that imbalanced neurotransmitter levels of excitation and inhibition are associated with HFA in adolescents., (Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.)

The timely identification of vehicles involved in an accident, such as a hit-and-run situation, bears great importance in forensics. To this end, procedures have been defined for analyzing car paint samples that combine techniques such as visual analysis and Fourier transform infrared spectroscopy. This work proposes a new methodology in order to automate the visual analysis using image retrieval. Specifically, color and texture information is extracted from a microscopic image of a recovered paint sample, and this information is then compared with the same features for a database of paint types, resulting in a shortlist of candidate paints. In order to demonstrate the operation of the methodology, a test database has been set up and two retrieval experiments have been performed. The first experiment quantifies the performance of the procedure for retrieving exact matches, while the second experiment emulates the real-life situation of paint samples that experience changes in color and texture over time., (Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.)

Working memory is a temporary storage system under attentional control. It is believed to play a central role in online processing of complex cognitive information and may also play a role in social cognition and interpersonal interactions. Adolescents with a disorder on the autism spectrum display problems in precisely these domains. Social impairments, communication difficulties, and repetitive interests and activities are core domains of autism spectrum disorders (ASD), and executive function problems are often seen throughout the spectrum. As the main cognitive theories of ASD, including the theory of mind deficit hypotheses, weak central coherence account, and the executive dysfunction theory, still fail to explain the broad spectrum of symptoms, a new perspective on the etiology of ASD is needed. Deficits in working memory are central to many theories of psychopathology, and are generally linked to frontal-lobe dysfunction. This article will review neuropsychological and (functional) brain imaging studies on working memory in adolescents with ASD. Although still disputed, it is concluded that within the working memory system specific problems of spatial working memory are often seen in adolescents with ASD. These problems increase when information is more complex and greater demands on working memory are made. Neuroimaging studies indicate a more global working memory processing or connectivity deficiency, rather than a focused deficit in the prefrontal cortex. More research is needed to relate these working memory difficulties and neuroimaging results in ASD to the behavioral difficulties as seen in individuals with a disorder on the autism spectrum.

Noonan syndrome is a relatively common autosomal dominant condition characterised by cardiac defects, short stature, feeding difficulties during the first year of life, and learning and behavioural problems later in life. The diagnosis is clinical and in 50% of cases it can be confirmed by a mutation in the PTPN11 gene. Studies into the effect of growth hormone treatment on final height have yet to provide any definite conclusions. Therefore, for the time being this treatment should be carried out in a research setting. Early-childhood feeding difficulties are troublesome. However, these disappear spontaneously and do not seem to negatively affect growth. Specific developmental patterns, resulting in behavioural and learning problems (non-verbal learning disability) are frequently encountered and require a specific approach.

Four families are described in which mental retardation segregates in an X-linked fashion. Mental retardation was the only consistent clinical finding in all affected males. The degree of retardation varied from mild to profound both between and within families. Linkage analysis localized the genetic defect of MRX43 to Xp22. 31-p21.2, MRX44 to Xp11.3-p11.21, MRX45 to Xp11.3-p11.21, and MRX52 to Xp11.21-q21.33 with LOD scores of >2 at straight theta = 0.0 in all four families., (Copyright 1999 Wiley-Liss, Inc.)

As part of an integrated approach to DNA-linkage analysis in X-linked mental retardation (XLMR), 29 members of five families suspected of having XLMR underwent psychometric assessment. Mental retardation was confirmed in all participants. The range of mental retardation varied from mild to profound within and between families. In addition, these preliminary results indicated family-specific cognitive profiles in MRX45 and MRX46. The fact that two non-overlapping loci were involved provides strong evidence that specific cognitive profiles are linked to specific loci (genes) in mental retardation. We therefore recommend the application of standardised psychometric tests for the assessment of XLMR.

This study addresses the assessment of developmental apraxia of speech (DAS) in children. For this, 11 children with a clear diagnosis of DAS were selected, based on documented speech history and perceptual evaluation of speech. The children with DAS, as well as 11 normal-speaking children, produced singleton real word and nonsense word imitations elicited in a standardised way. Phonetic transcriptions were analysed and errors in consonants classified. The results showed, firstly, that the children with DAS produced similar types of consonant errors as has been reported in the literature, which corroborates the method of elicitation as a valid procedure to assess relevant speech symptoms of DAS. Secondly, a large quantitative difference between children with DAS and normal-speaking children was found, in that children with DAS produced an overall higher rate of singleton consonant errors (substitutions, omissions, distortions) and cluster errors (cluster reductions) than the normal-speaking children. For the DAS group, the substitution-rate, particularly in real words (as opposed to nonsense words), was significantly correlated with severity as rated by two speech and language pathologists. This suggests that substitution-rate yields an adequate measure of severity of DAS. Thirdly, a qualitative difference between both subject groups emerged. Children with DAS did not benefit from the lexical status of the utterance (real versus nonsense word) to the same extent as normal-speaking children. Based on these findings the nature of the underlying deficits in speech production in DAS is discussed.

Developmental apraxia of speech is a disorder of phonological and articulatory output processes. However, it has been suggested that perceptual deficits may contribute to the disorder. Identification and discrimination tasks offer a fine-grained assessment of central auditory and phonetic functions. Seventeen children with developmental apraxia (mean age 8:9, years:months) and 16 control children (mean age 8:0) were administered tests of identification and discrimination of resynthesized and synthesized monosyllabic words differing in place-of-articulation of the initial voiced stop consonants. The resynthetic and synthetic words differed in the intensity of the third formant, a variable potentially enlarging their clinical value. The results of the identification task showed equal slopes for both subject groups, which indicates no phonetic processing deficit in developmental apraxia of speech. The hypothesized effect of the manipulation of the intensity of the third formant of the stimuli was not substantiated. However, the children with apraxia demonstrated poorer discrimination than the control children, which suggests affected auditory processing. Furthermore, analyses of discrimination performance and articulation data per apraxic subject demonstrated a specific relation between the degree to which auditory processing is affected and the frequency of place-of-articulation substitutions in production. This indicates the interdependence of perception and production. The results also suggest that the use of perceptual tasks has significant clinical value.