Age-matched Typically Developing Research Articles

Processing of Emotional Words in Children and Adolescents with Autism Spectrum Disorders.

Individuals with autism spectrum disorder (ASD) have difficulties in understanding emotional language, but little research has discussed the developmental course of the processing of emotional words in the clinical population. Previous studies have revealed distinct processing for emotion-label (e.g., happiness) and emotion-laden (e.g., birthday) words in typically developing (TD) children and adolescents. Extending these findings, the study used event-related potentials (ERPs) to explore the processing of these two types of emotional words in children and adolescents with ASD. The stimuli included two-character Chinese words with factors of word type (emotion-label versus emotion-laden) and valence (positive versus negative). The participants were 11 to 14-year-old children and adolescents with ASD (N = 23) and age-matched TD peers (N = 23). They categorized emotion valence for words while their brain responses were recorded. Both the TD and the ASD groups exhibited emotional processing for all emotional words across the N400 and late positivity component (LPC). The emotional processing was modulated by word type but varied with group and valence. A trend for group differences was observed in processing positive words at 500-600ms. In particular, the emotion effects of positive emotion-label words were positively correlated with social dysfunction across all participants. These findings suggested that children and adolescents with ASD have a selective impairment in understanding emotional concepts from language. The ERP measurements may reflect atypical emotional word processing for individuals with higher autistic severity in positive valence contexts.

What Silent Pauses Can 'Tell' Us About the Storytelling Skills of Autistic Children: Relations Between Pausing, Language Skills and Executive Functions.

Silent pauses may serve communicative purposes such as demarcating boundaries between discourse units in language production. Previous research has shown that autistic children differ in their pausing behavior from typically-developing (TD) peers, however, the factors behind this difference remain underexplored. The current study was aimed at comparing the use of silent pauses in the narrative production of autistic children and age-matched TD children, and also to identify possible relations between pausing behavior and the children's language and executive function abilities. According to the study's findings, the autistic children did not differ from their TD peers in the use of grammatical pauses, however, the former tended to produce significantly less syntactically complex narratives than the TD group, which increased the likelihood that the autistic group would pause appropriately at phrasal boundaries. Thoughwe have found low rates of ungrammatical silent pauses and omitted pauses in obligatory discourse contexts across both groups, autistic children with lower cognitive flexibility tended to use more ungrammatical pauses than their peers with higher cognitive flexibility scores. Also, the autistic group tended to omit obligatory silent pauses more often as their narration became more complex. The results demonstrate that syntactic complexity in narrative production modulated autistic children's pausing behavior, and that structurally simple narrations boosted the autistic group's appropriate use of grammatical pauses. The overall findings also demonstrate the importance of studying silent pauses in the narrative discourse of autistic children, and also highlight the links between silent pauses and the children's syntactic and cognitive skills.

Fine-needle percutaneous muscle microbiopsy technique as a feasible tool to address histological analysis in young children with cerebral palsy and age-matched typically developing children.

Cerebral palsy (CP) is a heterogeneous group of motor disorders attributed to a non-progressive lesion in the developing brain. Knowledge on skeletal muscle properties is important to understand the impact of CP and treatment but data at the microscopic levels are limited and inconsistent. Currently, muscle biopsies are collected during surgery and are restricted to CP eligible for such treatment or they may refer to another muscle or older children in typically developing (TD) biopsies. A minimally invasive technique to collect (repeated) muscle biopsies in young CP and TD children is needed to provide insights into the early muscle microscopic alterations and their evolution in CP. This paper describes the protocol used to 1) collect microbiopsies of the medial gastrocnemius (MG) and semitendinosus (ST) in CP children and age-matched TD children, 2) handle the biopsies for histology, 3) stain the biopsies to address muscle structure (Hematoxylin & Eosin), fiber size and proportion (myosin heavy chain), counting of the satellite cells (Pax7) and capillaries (CD31). Technique feasibility and safety as well as staining feasibility and measure accuracy were evaluated. Two microbiopsies per muscle were collected in 56 CP (5.8±1.1 yr) and 32 TD (6±1.1 yr) children using ultrasound-guided percutaneous microbiopsy technique. The biopsy procedure was safe (absence of complications) and well tolerated (Score pain using Wong-Baker faces). Cross-sectionally orientated fibers were found in 86% (CP) and 92% (TD) of the biopsies with 60% (CP) and 85% (TD) containing more than 150 fibers. Fiber staining was successful in all MG biopsies but failed in 30% (CP) and 16% (TD) of the ST biopsies. Satellite cell staining was successful in 89% (CP) and 85% (TD) for MG and in 70% (CP) and 90% (TD) for ST biopsies, while capillary staining was successful in 88% (CP) and 100% (TD) of the MG and in 86% (CP) and 90% (TD) for the ST biopsies. Intraclass coefficient correlation showed reliable and reproducible measures of all outcomes. This study shows that the percutaneous microbiopsy technique is a safe and feasible tool to collect (repeated) muscle biopsies in young CP and TD children for histological analysis and it provides sufficient muscle tissue of good quality for reliable quantification.

Relative clause comprehension in Cantonese-speaking children with and without developmental language disorder.

Developmental Language Disorder (DLD), present in 2 out of every 30 children, affects primarily oral language abilities and development in the absence of associated biomedical conditions. We report the first experimental study that examines relative clause (RC) comprehension accuracy and processing (via looking preference) in Cantonese-speaking children with and without DLD, testing the predictions from competing domain-specific versus domain-general theoretical accounts. We compared children with DLD (N = 22) with their age-matched typically-developing (TD) children (AM-TD, N = 23) aged 6;6-9;7 and language-matched (and younger) TD children (YTD, N = 21) aged 4;7-7;6, using a referent selection task. Within-subject factors were: RC type (subject-RCs (SRCs) versus object-RCs (ORCs); relativizer (classifier (CL) versus relative marker ge3 RCs). Accuracy measures and looking preference to the target were analyzed using generalized linear mixed effects models. Results indicated Cantonese children with DLD scored significantly lower than their AM-TD peers in accuracy and processed RCs significantly slower than AM-TDs, but did not differ from the YTDs on either measure. Overall, while the results revealed evidence of a SRC advantage in the accuracy data, there was no indication of additional difficulty associated with ORCs in the eye-tracking data. All children showed a processing advantage for the frequent CL relativizer over the less frequent ge3 relativizer. These findings pose challenges to domain-specific representational deficit accounts of DLD, which primarily explain the disorder as a syntactic deficit, and are better explained by domain-general accounts that explain acquisition and processing as emergent properties of multiple converging linguistic and non-linguistic processes.

Children with developmental coordination disorder are less able to fine-tune muscle activity in anticipation of postural perturbations than typically developing counterparts.

The majority of children with developmental coordination disorder (DCD) struggle with static and dynamic balance, yet there is limited understanding of the underlying neuromechanical mechanisms that underpin poor balance control in these children. Eighteen children with DCD and seven typically developing (TD) children aged 7-10 years stood with eyes open on a moveable platform progressively translated antero-posteriorly through three frequencies (0.1, 0.25 and 0.5 Hz). Myoelectric activity of eight leg muscles, whole-body 3D kinematics and centre of pressure were recorded. At each frequency, postural data were divided into transition-state and steady-state cycles. Data were analyzed using a linear mixed model with follow-up Tukey's pairwise comparisons. At the slowest frequency, children with DCD behaved like age-matched TD controls. At the fastest frequency, children with DCD took a greater number of steps, had a greater centre of mass variability, had a greater centre of pressure area, and tended to activate their muscles earlier and for longer than TD children. Children with DCD did not alter their postural response following prolonged exposure to platform movement, however they made more, non-structured postural adjustments in the medio-lateral direction as task difficulty increased. At the faster oscillation frequencies, children with DCD adopted a different muscle recruitment strategy to TD children. Activating their muscles earlier and for longer may suggest that children with DCD attempt to predict and react to postural disturbances, however the resulting anticipatory muscle excitation patterns do not seem as finely tuned to the perturbation as those demonstrated by TD children. Future work should examine the impact of balance training interventions on the muscle recruitment strategies of children with DCD, to ensure optimal interventions can be prescribed.

학령기 고기능 자폐범주성장애 아동의 발화유형 분석

This study investigated the types of utterances and analyzed the final functioning ending among Korean school-age children with high-functioning autism spectrum disorder (ASD) by using the story retelling task. A total of fifteen children with ASD and fifteen vocabulary ability–matched typically developing (TD) children participated in the study. The utterances according to final and connective ending, fragment utterance, and incompletion for grammar were analyzed. The ASD group exhibited lower performances than the TD group on the utterance type analysis, however, there were no significant differences between the two groups. The results reveal that the ASD group produce similar utterance types in story retelling task with the language age-matched TD children. Furthermore, the results indicate that the utterance type analysis can be useful in assessing the language ability of school-age children with ASD.

Acquisition of grammatical aspect by Mandarin-speaking preschool children with autism spectrum disorder.

Mandarin-speaking children with autism spectrum disorder (ASD) have difficulties producing aspect markers. The difficulties were explained in terms of pragmatic deficits since these children demonstrated strength in the comprehension of aspect markers using the Intermodal Preferential Looking (IPL) task. To verify whether this dissociation between production and comprehension could be replicated using another technique to the IPL, and if all children with ASD show difficulties in the production of aspect markers. A total of 34 children with ASD without cognitive delay, half with language impairment (ALI; mean age = 61.25 months old) and half with normal language (ALN, mean age = 61.52 months old), as well as 17 age-matched typically developing (TD) children (mean age = 61.38 months old) participated in a sentence-picture-matching task and a priming picture-description task to investigate their comprehension and production of Mandarin aspect markers zai-, -le and -zhe. In the comprehension task, children in the ALN group performed similarly to their TD peers, but those in the ALI group were less accurate on zai- and -le than TD children; children in all groups received higher accuracy when zai- was combined with Activity rather than Accomplishment verbs, and those in the ALI group was also more accurate when -le occurred with Achievement verbs, in contrast to Activity verbs. In the production task, children in the ALI group produced fewer targets and more irrelevant sentences with zai- than their TD peers, and they tended to produce bare verbs for -le and -zhe than TD children; children in all groups tended to combine zai- with Activity verbs, and those in the ALN group also tended to combine -le with Achievement verbs. The comprehension and production of Mandarin aspect markers by children with ASD are linked to general language abilities, and interactions between lexical and grammatical aspect. Patterns of performance are similar to those of TD peers only for the subgroup with spared global language, while pragmatic deficits are pervasive throughout the spectrum. Therefore, training on formal language, with a specific emphasis on aspectual rather than pragmatic abilities, may be more effective at enhancing the production of aspect markers. What is already known on this subject Mandarin-speaking children with ASD have difficulties producing aspect markers but demonstrate strengths in aspectual comprehension via the IPL task. Therefore, it has been proposed that their 'specific' difficulties in aspectual production should be ascribed to their pragmatic deficits. However, pragmatic deficits are highly pervasive in children with ASD while only a subgroup of children with ASD who are impaired in language development (children with ALI) show difficulties in producing tense/aspect morphology. Pursuing this reasoning, pragmatic deficits might not be the critical factor impacting the performance of children with ASD in aspectual production. What this study adds Children with ASD were divided into one group with ALI and the other with normal language (ALN). Results of a sentence-picture-matching and a priming picture-description task illustrated that both groups preserved the comprehension of Mandarin aspect markers zai-, -le and -zhe. However, children with ALI performed worse than age-matched TD children, while children with ALN demonstrated similar performance to TD children in aspectual production. These findings, coupled with the fact that pragmatic challenges affect individuals throughout the spectrum, suggest that general language abilities rather than pragmatics better explain the performance of children with ASD on aspectual production. What are the potential or actual clinical implications of this work? Since general language abilities rather than pragmatic deficits of children with ASD determine their performance on the production of aspect markers, direct training on the use of aspect markers or more global language therapy could benefit children with ASD in the production of aspect markers.

Acoustic and Semantic Processing of Auditory Scenes in Children with Autism Spectrum Disorders

Purpose: Processing real-world sounds requires acoustic and higher-order semantic information. We tested the theory that individuals with autism spectrum disorder (ASD) show enhanced processing of acoustic features and impaired processing of semantic information. Methods: We used a change deafness task that required detection of speech and non-speech auditory objects being replaced and a speech-in-noise task using spoken sentences that must be comprehended in the presence of background speech to examine the extent to which 7–15 year old children with ASD (n = 27) rely on acoustic and semantic information, compared to age-matched (n = 27) and IQ-matched (n = 27) groups of typically developing (TD) children. Within a larger group of 7–15 year old TD children (n = 105) we correlated IQ, ASD symptoms, and the use of acoustic and semantic information. Results: Children with ASD performed worse overall at the change deafness task relative to the age-matched TD controls, but they did not differ from IQ-matched controls. All groups utilized acoustic and semantic information similarly and displayed an attentional bias towards changes that involved the human voice. Similarly, for the speech-in-noise task, age-matched–but not IQ-matched–TD controls performed better overall than the ASD group. However, all groups used semantic context to a similar degree. Among TD children, neither IQ nor the presence of ASD symptoms predict the use of acoustic or semantic information. Conclusion: Children with and without ASD used acoustic and semantic information similarly during auditory change deafness and speech-in-noise tasks.

Increased muscle responses to balance perturbations in children with cerebral palsy can be explained by increased sensitivity to center of mass movement

BackgroundBalance impairments are common in children with cerebral palsy (CP). Muscle activity during perturbed standing is higher in children with CP than in typically developing (TD) children, but we know surprisingly little about how sensorimotor processes for balance control are altered in CP. Sensorimotor processing refers to how the nervous system translates incoming sensory information about body motion into motor commands to activate muscles. In healthy adults, muscle activity in response to backward support-surface translations during standing can be reconstructed by center of mass (CoM) feedback, i.e., by a linear combination of delayed (due to neural transmission times) CoM displacement, velocity, and acceleration. The level of muscle activity in relation to changes in CoM kinematics, i.e., the feedback gains, provides a metric of the sensitivity of the muscle response to CoM perturbations. Research questionCan CoM feedback explain reactive muscle activity in children with CP, yet with higher feedback gains than in TD children? MethodsWe perturbed standing balance by backward support-surface translations of different magnitudes in 20 children with CP and 20 age-matched TD children and investigated CoM feedback pathways underlying reactive muscle activity in the triceps surae and tibialis anterior. ResultsReactive muscle activity could be reconstructed by delayed feedback of CoM kinematics and hence similar sensorimotor pathways might underlie balance control in children with CP and TD children. However, sensitivities of both agonistic and antagonistic muscle activity to CoM displacement and velocity were higher in children with CP than in TD children. The increased sensitivity of balance correcting responses to CoM movement might explain the stiffer kinematic response, i.e., smaller CoM movement, observed in children with CP. SignificanceThe sensorimotor model used here provided unique insights into how CP affects neural processing underlying balance control. Sensorimotor sensitivities might be a useful metric to diagnose balance impairments.

Not only motor skill performance but also haptic function is impaired in children with developmental language disorder

BackgroundPrevious studies have found an association between motor immaturity and developmental language impairment in children. However, systematic investigations of somatosensory dysfunctions that might be linked to motor deficits in children with developmental language disorder (DLD) are lacking. AimsExamined haptic perception and motor skills in school-age children with DLD and typically-developing (TD) children. MethodsSixteen children with DLD and sixteen age-matched TD children performed a curvature detection task measuring haptic sensitivity and a curvature discrimination task measuring haptic acuity. The Movement Assessment Battery for Children, 2nd edition (MABC-2) was also conducted to evaluate children’s motor ability. ResultsThe results revealed elevated thresholds of both haptic detection (67.5%) and haptic discrimination (67.9%) in the DLD group when compared to the TD group. In addition, the children with DLD performed significantly less well on the manual dexterity of MABC-2. Finally, a lower haptic acuity was associated with poorer manual dexterity scores of MABC-2. ConclusionsThis study demonstrates for the first time that not only motor skills, but also haptic function is altered in children with DLD. The observed association between manual dexterity and haptic acuity suggests a close relationship between haptic and motor skills in school-age children.

The developmental trajectory of sleep in children with Smith-Magenis syndrome compared to typically developing peers: a 3-year follow-up study.

To determine the trajectory of: (i) objective sleep parameters and (ii) caregiver-reported sleep questionnaire scores over 3 years in children with Smith-Magenis syndrome (SMS) compared to age-matched typically developing (TD) controls. We also aimed to (iii) describe individual profiles of change in sleep parameters over time. Week-long, overnight actigraphy and questionnaire data from 13 children with SMS and 13 age-matched TD children were collected at Time 1 and Time 2 (3 years later). Independent samples t-tests, paired samples t-tests, and Bayesian analyses were used to compare sleep parameters and sleep questionnaire scores between groups at each time point and compare data within groups to assess change over time. Sleep parameters were consistently more disrupted in the SMS group than the TD group, with significantly reduced sleep efficiency, increased wake after sleep onset and earlier get up times at both time points. This was mirrored in the questionnaire data, with children with SMS evidencing higher scores for overall sleep disturbance, night waking, and daytime sleepiness. While TD sleep parameters demonstrated expected developmental changes over 3 years, in the SMS group sleep parameters and variability between and within children remained largely stable. However, some children with SMS showed substantial variation in sleep parameters over time. Questionnaire scores remained stable over 3 years in both groups. Overall, sleep disturbance appears to be a stable feature of SMS, indicative of a divergent sleep trajectory compared to TD peers. Proactive intervention approaches should be considered for poor sleep in SMS.

Motor abilities of children with childhood apraxia of speech

Previous studies on fine and gross motor skills of children with childhood apraxia of speech (CAS) have reported inconclusive results. In this study, we investigate the motor abilities of children with CAS by focusing on three distinct motor factors: control during movement, fine motor skills/handwriting, and general coordination. Participants included 25 children with CAS and 20 age-matched typically developing (TD) children between the ages of 5 and 7 years. Motor abilities were evaluated using a parent questionnaire - the Croatian version of The Developmental Coordination Disorder Questionnaire (DCDQ-HR). Compared to age-matched TD children, those with CAS showed significantly poorer overall motor ability based on the DCDQ-HR, as well as on all three motor factors: control during movement, fine motor skills/handwriting, and general coordination. Even though their results were worse than TD children, they were still within the range that indicates normal motor abilities. Among the three motor factors considered, children with CAS exhibited significant problems with fine motor skills/handwriting. Children with CAS may not be categorised as children with motor deficits, but they exhibit poor overall motor abilities, especially fine motor skills, compared to TD children. This study supports the premise that co-occurring language impairment is an important variable to consider when discussing motor abilities in CAS.

The comprehension and production of Wh- questions among Malay children with developmental language disorders: Climbing the syntactic tree.

This study is an investigation of both comprehension and production of Wh- questions in Malay-speaking children with a developmental language disorder (DLD). A total of 15 Malay children with DLD (ages 7;0-9;11 years) were tested on a set of Wh- questions (who subject and object, which subject and object), comparing their performance with two control groups [15 age-matched typically developing (TD) children and 15 younger TD language-matched children]. Malay children with DLD showed a clear asymmetry in comprehension of Wh- questions, with a selective impairment for which NP questions compared with who questions. Age-matched controls performed at ceiling in all Wh- questions, while the language-matched group reported a subject/object asymmetry selective for the which NP, as reported in other languages. In production, both children with DLD and younger children showed a preference for questions with in situ Wh- elements, a structure that is allowed in colloquial Malay, but which is not produced by the age-matched TD group. Several non-adult-like strategies were adopted particularly by the children with DLD to avoid complex sentences, including substitution with yes/no echo questions, production of the wrong Wh- question, and use of a generic Wh- element. The study provides an insight on the mastery of Wh- questions in both typical Malay children and children with DLD. Implications for the definition of a clinical marker for DLD in a free word order language with Wh- in situ option will be discussed.

External walking environment differentially affects muscle synergies in children with cerebral palsy and typical development.

Despite external environmental changes in walking, such as manipulating gait speed, previous studies have shown that the underlying muscle synergy structures (synergy weights or vectors) rarely vary. The purpose of this study is to examine if external environmental changes to the walking task influence muscle synergies in children with cerebral palsy (CP) and/or typical development (TD). To identify muscle synergies, we extracted muscle synergies from eight children with CP and eight age-matched TD in three treadmill walking conditions, e.g., baseline (adjusted to individual comfortable walking speed), variable speed (VS), or restricted foot width (RW). Then, we grouped similar muscle synergies using k-mean clustering and discriminant analyses from all datasets of individual synergy structures. Proportion tests exhibited six clusters of muscle synergies predominantly arising from children with CP and four clusters from children with TD. Also, the proportion of muscle synergies was significantly different in four of the CP-preferred clusters across conditions. Specifically, the proportion of the baseline condition was significantly different from VS and RW conditions in one and two clusters, respectively. The proportion was significantly different between VS and RW conditions in four clusters. Cadence and step lengths differed across conditions but not groups which makes the group differences in proportion even more notable. In contrast, step width, while significantly lower in CP, did not differ across conditions. Our findings demonstrate that muscle synergies in children with CP are more sensitive to changes in the external walking environment than in typically developing children.

Characteristics of Fictional Stories in Children with Autism Spectrum Disorder: Evidence from the Farsi

Background: Narrative ability is a critical component of social communication essential for participating in everyday activities. Children with autism spectrum disorder (ASD) demonstrate problems in the narrative discourse, but little is known about the features of their fictional stories. Objectives: This study compared fictional narratives between ASD children and they’re typically developing (TD) peers. Methods: Fictional stories produced by 6- to-7-year-old males with high functioning autism (n = 14) were compared with language, sex, and age-matched TD children (n = 15). The stories were analyzed using the monitoring indicators of scholarly language. The macrostructure and microstructure elements, narrative complexity index, story knowledge index, and perspective-taking index were compared between the two groups by one-way analysis of variance (ANOVA) at the significance level of 0.05. Results: The scores of macrostructure and microstructure elements were lower in children with ASD. The ANOVA showed significant differences between ASD and TD children in three indices (P < 0.05). Moreover, the Pearson correlation coefficients between the total macrostructure and microstructure scores were close to one in both ASD (r = 0.89) and TD children (r = 0.93). Conclusions: Despite obtaining scores in the average range in a standard language test, Farsi-speaking children with ASD experience limitations in fictional narratives.

What Ability Can Predict Mathematics Performance in Typically Developing Preschoolers and Those with Autism Spectrum Disorder?

Research evaluating predictors of mathematics ability in preschoolers with autism spectrum disorder (ASD) is scarce and inconclusive. The present study first compared the mathematics ability and cognitive abilities of preschoolers with ASD and age-matched typically developing (TD) peers. Then, we examined the relative contributions of cognitive abilities to the mathematics ability of preschoolers with ASD and TD. The results show that compared to those of their age-matched TD peers, the mathematics and cognitive abilities of preschoolers with ASD were impaired. The predictors of mathematics ability were found to differ among preschoolers with ASD and their age-matched TD peers. For TD preschoolers, the domain-specific approximate number system (ANS) was the key predictor of mathematics ability. For preschoolers with ASD, domain-general working memory (WM) was most important.

Visual perceptual salience and novel referent selection in children with and without autism spectrum disorder.

Many young children with autism spectrum disorder (ASD) demonstrate striking delays in early vocabulary development. Experimental studies that teach the meanings of novel nonwords can determine the effects of linguistic and attentional factors. One factor that may affect novel referent selection in children with ASD is visual perceptual salience-how interesting (i.e., striking) stimuli are on the basis of their visual properties. The goal of the current study was to determine how the perceptual salience of objects affected novel referent selection in children with ASD and children who are typically developing (TD) of similar ages (mean age 3-4 years). Using a screen-based experimental paradigm, children were taught the names of four unfamiliar objects: two high-salience objects and two low-salience objects. Their comprehension of the novel words was assessed in low-difficulty and high-difficulty trials. Gaze location was determined from video by trained research assistants. Contrary to initial predictions, findings indicated that high perceptual salience disrupted novel referent selection in the children with ASD but facilitated attention to the target object in age-matched TD peers. The children with ASD showed no significant evidence of successful novel referent selection in the high-difficulty trials. Exploratory reaction time analyses suggested that the children with autism showed "stickier" attention-had more difficulty disengaging (i.e., looking away)-from high-salience distracter images than low-salience distracter images, even though the two images were balanced in salience for any given test trial. These findings add to growing evidence that high perceptual salience has the potential to disrupt novel referent selection in children with ASD. These results underscore the complexity of novel referent selection and highlight the importance of taking the immediate testing context into account. In particular, it is important to acknowledge that screen-based assessments and screen-based learning activities used with children with ASD are not immune to the effects of lower level visual features, such as perceptual salience.

Verb morphology in Turkish-speaking children with and without DLD: the role of morphophonology

ABSTRACT In this study, we examined the verb morphology system of Turkish-speaking preschoolers with developmental language disorder (DLD) and compared their use to that of two groups of typically developing (TD) children. We report data from a total of 80 monolingual children – 40 children with DLD, 20 TD age-matched children and 20 TD younger MLU-matched children. Language samples obtained from the children served as the source of the data. The results show that the children with DLD were less accurate in their use of verb suffixes than both the younger and the age-matched TD children. The most frequent error types included use of bare stems, omission of the suffix, and replacing one finite verb suffix with another. The distinction between witnessed past and reported past also posed a challenge. Multi-level model results showed that phonemic length and irregular morphophonology were the best predictors of the children’s level of accuracy. These results indicate that even though Turkish is considered a “verb friendly” language, children with DLD do not succeed in closing the gap with their TD peers. The complex interplay of morphology and phonology in Turkish appears to be the major obstacle for children with DLD acquiring this agglutinative language.

Relationship between Short-Range and Homotopic Long-Range Resting State Functional Connectivity in Temporal Lobes in Autism Spectrum Disorder.

To investigate the relationship between short-range and homotopic long-range resting state functional connectivity (RSFC) in children with autism spectrum disorder (ASD) and typically developing (TD) children, we analyzed functional near-infrared spectroscopy (fNIRS) RSFC in 25 children with ASD and 22 age-matched TD children. The resting state fNIRS signals, including spontaneous fluctuations in the oxygenated hemoglobin (HbO2) and deoxygenated hemoglobin (Hb) concentrations, were recorded from the bilateral temporal lobes. We found that (1) there was no difference in the short-range RSFC between the left and right hemisphere in either ASD or TD group; (2) both the short-range and homotopic long-range RSFC were weaker in the ASD than TD group; and (3) the short-range RSFC was stronger than the homotopic long-range RSFC in the ASD group, whereas no such difference was observed in the TD group. These observations might be helpful for a better understanding of the underlying cortical mechanism in ASD.

Locomotor Assisted Therapy's Influence on Lower Extremity Muscle Activation Patterns in Typically Developing Children and Children With Cerebral Palsy

<h3>Research Objectives</h3> To compare muscle activation patterns of children with cerebral palsy (CP) and typically developing (TD) in overground (OG) and driven gait orthosis (DGO) walking. To compare within group variability of each muscle and walking condition. <h3>Design</h3> Nonrandomized controlled trial, no follow-up. <h3>Setting</h3> Neuroscience Center at IU Health (primary care facility). <h3>Participants</h3> Volunteer sample of twenty subjects, 10 with CP and 10 age-matched TD, aged 4 to 11 years. CP inclusion criteria: ability to ambulate 20 feet barefoot and ability to follow one step directions. Exclusion criteria: Botox to the lower extremity in last 3 months and history of tendon transfer. No subjects refused or withdrew. <h3>Interventions</h3> Rectus femoris (RF), semitendinosus (ST), gluteus maximus (GMax), and gluteus medius (GMed) surface EMG were recorded in OG and DGO conditions for three 10 second intervals. <h3>Main Outcome Measures</h3> Averaged surface EMG gait cycle time normalized values. <h3>Results</h3> Between group muscle activation pattern analysis revealed consistent differences (p < .05) in terminal stance, pre-swing, and initial swing phases of gait with greater muscle unit recruitment during DGO walking. Within group variability of the muscle activation patterns revealed lower muscle activation variability in CP DGO walking (RF 52.82%, ST 69.20%, GMax 20.36%, GMed 49.74%) compared to CP OG (RF 51.40%, ST 38.50%, GMax 5.62%, GMed 37.04%). <h3>Conclusions</h3> Decreased variability indicates that walking in the DGO provided measurably repetitive movement. Consistent elevated muscle unit recruitment noted in DGO walking in terminal stance, pre-swing, and initial swing may be due to the negative effect that the DGO parameters of guidance force, body weight support, and speed may have on ground reaction force. With the goal of normalizing functional gait, study on the effect of these parameters on ground reaction forces is needed. <h3>Author(s) Disclosures</h3> N/A.