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Charles A Nelson - One of the best experts on this subject based on the ideXlab platform.
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Lateralization of erps to speech and handedness in the early development of autism spectrum disorder
Journal of Neurodevelopmental Disorders, 2017Co-Authors: Kayla H Finch, Charles A Nelson, Anne M Seery, Meagan R Talbott, Helen TagerflusbergAbstract:Language is a highly lateralized function, with typically developing individuals showing left hemispheric specialization. Individuals with autism spectrum disorder (ASD) often show reduced or reversed hemispheric Lateralization in response to language. However, it is unclear when this difference emerges and whether or not it can serve as an early ASD biomarker. Additionally, atypical language Lateralization is not specific to ASD as it is also seen more frequently in individuals with mixed- and left-handedness. Here, we examined early asymmetry patterns measured through neural responses to speech sounds at 12 months and behavioral observations of handedness at 36 months in children with and without ASD. Three different groups of children participated in the study: low-risk controls (LRC), high risk for ASD (HRA; infants with older sibling with ASD) without ASD, and HRA infants who later receive a diagnosis of ASD (ASD). Event-related potentials (ERPs) to speech sounds were recorded at 12 months. Utilizing a novel observational approach, handedness was measured by hand preference on a variety of behaviors at 36 months. At 12 months, Lateralization patterns of ERPs to speech stimuli differed across the groups with the ASD group showing reversed Lateralization compared to the LRC group. At 36 months, factor analysis of behavioral observations of hand preferences indicated a one-factor model with medium to high factor loadings. A composite handedness score was derived; no group differences were observed. There was no association between Lateralization to speech at 12 months and handedness at 36 months in the LRC and HRA groups. However, children with ASD did show an association such that infants with Lateralization patterns more similar to the LRC group at 12 months were stronger right-handers at 36 months. These results highlight early developmental patterns that might be specific to ASD, including a potential early biomarker of reversed Lateralization to speech stimuli at 12 months, and a relation between behavioral and neural asymmetries. Future investigations of early asymmetry patterns, especially atypical hemispheric specialization, may be informative in the early identification of ASD.
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atypical hemispheric specialization for faces in infants at risk for autism spectrum disorder
Autism Research, 2015Co-Authors: Brandon Keehn, Vanessa Vogelfarley, Charles A Nelson, Helen TagerflusbergAbstract:Among the many experimental findings that tend to distinguish those with and without autism spectrum disorder (ASD) are face processing deficits, reduced hemispheric specialization, and atypical neurostructural and functional connectivity. To investigate the earliest manifestations of these features, we examined Lateralization of event-related gamma-band coherence to faces during the first year of life in infants at high-risk for autism (HRA; defined as having an older sibling with ASD) who were compared low-risk comparison (LRC) infants, defined as having no family history of ASD. Participants included 49 HRA and 46 LRC infants who contributed a total of 127 data sets at 6- and 12-months. EEG was recorded while infants viewed images of familiar/unfamiliar faces. Event-related gamma-band (30-50Hz) phase coherence between anterior-posterior electrode pairs for left and right hemispheres was computed. Developmental trajectories for Lateralization of intra-hemispheric coherence were significantly different in HRA and LRC infants: by 12-months HRA infants showed significantly greater leftward Lateralization compared to LRC infants who showed rightward Lateralization. Preliminary results indicate that infants who later met criteria for ASD were those that showed the greatest leftward Lateralization. HRA infants demonstrate an aberrant pattern of leftward Lateralization of intra-hemispheric coherence by the end of the first year of life, suggesting that the network specialized for face processing may develop atypically. Further, infants with the greatest leftward asymmetry at 12-months where those that later met criteria for ASD, providing support to the growing body of evidence that atypical hemispheric specialization may be an early neurobiological marker for ASD.
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atypical Lateralization of erp response to native and non native speech in infants at risk for autism spectrum disorder
Developmental Cognitive Neuroscience, 2013Co-Authors: Anne M Seery, Vanessa Vogelfarley, Charles A Nelson, Helen TagerflusbergAbstract:Language impairment is common in autism spectrum disorders (ASD) and is often accompanied by atypical neural Lateralization. However, it is unclear when in development language impairment or atypical Lateralization first emerges. To address these questions, we recorded event-related-potentials (ERPs) to native and non-native speech contrasts longitudinally in infants at risk for ASD (HRA) over the first year of life to determine whether atypical Lateralization is present as an endophenotype early in development and whether these infants show delay in a very basic precursor of language acquisition: phonemic perceptual narrowing. ERP response for the HRA group to a non-native speech contrast revealed a trajectory of perceptual narrowing similar to a group of low-risk controls (LRC), suggesting that phonemic perceptual narrowing does not appear to be delayed in these high-risk infants. In contrast there were significant group differences in the development of lateralized ERP response to speech: between 6 and 12 months the LRC group displayed a lateralized response to the speech sounds, while the HRA group failed to display this pattern. We suggest the possibility that atypical Lateralization to speech may be an ASD endophenotype over the first year of life.
Rene S Kahn - One of the best experts on this subject based on the ideXlab platform.
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linkage analysis in a dutch population isolate shows no major gene for left handedness or atypical language Lateralization
The Journal of Neuroscience, 2015Co-Authors: Metten Somers, Roel A Ophoff, Maartje F Aukes, Rita M Cantor, Marco P M Boks, Meenakshi Dauwan, Kees L De Visser, Rene S KahnAbstract:Cerebral dominance of language function and hand preference are suggested to be heritable traits with possible shared genetic background. However, joined genetic studies of these traits have never been conducted. We performed a genetic linkage study in 37 multigenerational human pedigrees of both sexes (consisting of 355 subjects) enriched with left-handedness in which we also measured language Lateralization. Hand preference was measured with the Edinburgh Handedness Inventory, and language Lateralization was measured with functional transcranial Doppler during language production. The estimated heritability of left-handedness and language Lateralization in these pedigrees is 0.24 and 0.31, respectively. A parametric major gene model was tested for left-handedness. Nonparametric analyses were performed for left-handedness, atypical Lateralization, and degree of language Lateralization. We did not observe genome-wide evidence for linkage in the parametric or nonparametric analyses for any of the phenotypes tested. However, multiple regions showed suggestive evidence of linkage. The parametric model showed suggestive linkage for left-handedness in the 22q13 region [heterogeneity logarithm of odds (HLOD) = 2.18]. Nonparametric multipoint analysis of left-handedness showed suggestive linkage in the same region [logarithm of odds (LOD) = 2.80]. Atypical language Lateralization showed suggestive linkage in the 7q34 region (LODMax = 2.35). For strength of language Lateralization, we observed suggestive linkage in the 6p22 (LODMax = 2.54), 7q32 (LODMax = 1.93), and 9q33 (LODMax = 2.10) regions. We did not observe any overlap of suggestive genetic signal between handedness and the extent of language Lateralization. The absence of significant linkage argues against the presence of a major gene coding for both traits; rather, our results are suggestive of these traits being two independent polygenic complex traits.
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sex differences in handedness asymmetry of the planum temporale and functional language Lateralization
Brain Research, 2008Co-Authors: Iris E C Sommer, Andre Aleman, Metten Somers, Marco P M Boks, Rene S KahnAbstract:Many studies have investigated sex differences in language Lateralization. Despite the large number of investigations, controversy about the presence of sex differences in Lateralization remains. This study aims to provide a complete overview of sex differences in several reflections of language Lateralization: handedness, asymmetry of the Planum Temporale (PT) and functional Lateralization of language, measured by asymmetric performance on dichotic listening tests (Right Ear Advantage) and asymmetry of language activation as measured with functional imaging techniques. Meta-analysis of studies that assessed handedness in males and females yielded more left-handedness in males (mean weighted odds ratio: 1.25, p < 0.001). Meta-analysis of studies on PT asymmetry yielded no sex difference (Hedges g = − 0.11, p = 0.68). Results of the meta-analysis on dichotic listening studies also retrieved no sex difference in Lateralization (Hedges g = 0.09, p = 0.18). When the studies were subdivided according to the paradigm they applied, studies that used the consonant–vowel task yielded a sex difference favouring males, while studies that applied other paradigms yielded no sex difference. The subdivision into applied paradigm largely overlapped with the subdivision into studies that did or did not focus on sex differences as their main topic. The observed sex effect may therefore be caused by publication bias. Meta-analysis of functional imaging studies yielded no sex difference (Hedges g = 0.01, p = 0.73) in language Lateralization. Sub-analyses of studies that applied different paradigms all yielded no sex difference. In conclusion, males are more frequently non-right handed than females, but there is no sex difference in asymmetries of the Planum Temporale, dichotic listening or functional imaging findings during language tasks.
G. Bashford - One of the best experts on this subject based on the ideXlab platform.
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Functional Transcranial Doppler Ultrasound for Measurement of Hemispheric Lateralization During Visual Memory and Visual Search Cognitive Tasks
IEEE Transactions on Ultrasonics Ferroelectrics and Frequency Control, 2016Co-Authors: B. Hage, M. Alwatban, E. Barney, M. Mills, E. Truemper, Michael D. Dodd, G. BashfordAbstract:Functional transcranial Doppler ultrasound (fTCD) is a noninvasive sensing modality that measures cerebral blood flow velocity (CBFV) with high temporal resolution. CBFV change is correlated to changes in cerebral oxygen uptake, enabling fTCD to measure brain activity and Lateralization with high accuracy. However, few studies have examined the relationship of CBFV change during visual search and visual memory tasks. Here a protocol to compare Lateralization between these two similar cognitive tasks using fTCD is demonstrated. Ten healthy volunteers (age 21±2 years) were shown visual scenes on a computer and performed visual search and visual memory tasks while CBFV in the bilateral middle cerebral arteries was monitored with fTCD. Each subject completed 40 trials, consisting of baseline (25 s), calibration (variable), instruction (2.5 s), and task (20 s) epochs. Lateralization was computed for each task by calculating the bilateral CBFV envelope percent change from baseline and subtracting the right side from the left side. The results showed significant Lateralization (p
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Functional transcranial Doppler ultrasound for high temporal resolution measurement of Lateralization in visual memory and visual search cognitive tasks
2015 IEEE International Ultrasonics Symposium (IUS), 2015Co-Authors: B. Hage, M. Alwatban, E. Barney, M. Mills, M. Dodd, E. Truemper, G. BashfordAbstract:Functional transcranial Doppler ultrasound (fTCD) is a non-invasive sensing modality that measures blood flow velocities in cerebral arteries (CBFV) with high temporal resolution. Few studies have examined the relationship of CBFV change during visual search and visual memory cognitive tasks. Here a protocol to compare Lateralization between these two similar tasks using fTCD is demonstrated. Thirteen healthy volunteers were shown visual scenes on a computer and performed visual search and visual memory tasks while CBFV in the bilateral middle cerebral arteries was monitored with fTCD. Each subject completed 40 trials, consisting of baseline, calibration, instruction, and task periods. Lateralization was computed for each trial by subtracting the percent increase in CBFV on the right side from that on the left side. Results showed significant Lateralization of both tasks, with memory reaching left Lateralization of 1.3 percent, and search reaching right Lateralization of 0.5 percent, agreeing with the hypothesis that memory is more left lateralized and search is more right lateralized. The protocol is straightforward and the equipment inexpensive, introducing a low-cost, high temporal resolution technique to further study Lateralization of the brain.
Heath B Henninger - One of the best experts on this subject based on the ideXlab platform.
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effect of lateral offset center of rotation in reverse total shoulder arthroplasty a biomechanical study
Journal of Shoulder and Elbow Surgery, 2012Co-Authors: Heath B Henninger, Alexej Barg, Andrew E Anderson, Kent N Bachus, Robert T Burks, Robert Z TashjianAbstract:Background Lateral offset center of rotation (COR) reduces the incidence of scapular notching and potentially increases external rotation range of motion (ROM) after reverse total shoulder arthroplasty (rTSA). The purpose of this study was to determine the biomechanical effects of changing COR on abduction and external rotation ROM, deltoid abduction force, and joint stability. Materials and methods A biomechanical shoulder simulator tested cadaveric shoulders before and after rTSA. Spacers shifted the COR laterally from baseline rTSA by 5, 10, and 15 mm. Outcome measures of resting abduction and external rotation ROM, and abduction and dislocation (lateral and anterior) forces were recorded. Results Resting abduction increased 20° vs native shoulders and was unaffected by COR Lateralization. External rotation decreased after rTSA and was unaffected by COR Lateralization. The deltoid force required for abduction significantly decreased 25% from native to baseline rTSA. COR Lateralization progressively eliminated this mechanical advantage. Lateral dislocation required significantly less force than anterior dislocation after rTSA, and both dislocation forces increased with Lateralization of the COR. Conclusion COR Lateralization had no influence on ROM (adduction or external rotation) but significantly increased abduction and dislocation forces. This suggests the lower incidence of scapular notching may not be related to the amount of adduction deficit after lateral offset rTSA but may arise from limited impingement of the humeral component on the lateral scapula due to a change in joint geometry. Lateralization provides the benefit of increased joint stability, but at the cost of increasing deltoid abduction forces.
Helen Tagerflusberg - One of the best experts on this subject based on the ideXlab platform.
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Lateralization of erps to speech and handedness in the early development of autism spectrum disorder
Journal of Neurodevelopmental Disorders, 2017Co-Authors: Kayla H Finch, Charles A Nelson, Anne M Seery, Meagan R Talbott, Helen TagerflusbergAbstract:Language is a highly lateralized function, with typically developing individuals showing left hemispheric specialization. Individuals with autism spectrum disorder (ASD) often show reduced or reversed hemispheric Lateralization in response to language. However, it is unclear when this difference emerges and whether or not it can serve as an early ASD biomarker. Additionally, atypical language Lateralization is not specific to ASD as it is also seen more frequently in individuals with mixed- and left-handedness. Here, we examined early asymmetry patterns measured through neural responses to speech sounds at 12 months and behavioral observations of handedness at 36 months in children with and without ASD. Three different groups of children participated in the study: low-risk controls (LRC), high risk for ASD (HRA; infants with older sibling with ASD) without ASD, and HRA infants who later receive a diagnosis of ASD (ASD). Event-related potentials (ERPs) to speech sounds were recorded at 12 months. Utilizing a novel observational approach, handedness was measured by hand preference on a variety of behaviors at 36 months. At 12 months, Lateralization patterns of ERPs to speech stimuli differed across the groups with the ASD group showing reversed Lateralization compared to the LRC group. At 36 months, factor analysis of behavioral observations of hand preferences indicated a one-factor model with medium to high factor loadings. A composite handedness score was derived; no group differences were observed. There was no association between Lateralization to speech at 12 months and handedness at 36 months in the LRC and HRA groups. However, children with ASD did show an association such that infants with Lateralization patterns more similar to the LRC group at 12 months were stronger right-handers at 36 months. These results highlight early developmental patterns that might be specific to ASD, including a potential early biomarker of reversed Lateralization to speech stimuli at 12 months, and a relation between behavioral and neural asymmetries. Future investigations of early asymmetry patterns, especially atypical hemispheric specialization, may be informative in the early identification of ASD.
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atypical hemispheric specialization for faces in infants at risk for autism spectrum disorder
Autism Research, 2015Co-Authors: Brandon Keehn, Vanessa Vogelfarley, Charles A Nelson, Helen TagerflusbergAbstract:Among the many experimental findings that tend to distinguish those with and without autism spectrum disorder (ASD) are face processing deficits, reduced hemispheric specialization, and atypical neurostructural and functional connectivity. To investigate the earliest manifestations of these features, we examined Lateralization of event-related gamma-band coherence to faces during the first year of life in infants at high-risk for autism (HRA; defined as having an older sibling with ASD) who were compared low-risk comparison (LRC) infants, defined as having no family history of ASD. Participants included 49 HRA and 46 LRC infants who contributed a total of 127 data sets at 6- and 12-months. EEG was recorded while infants viewed images of familiar/unfamiliar faces. Event-related gamma-band (30-50Hz) phase coherence between anterior-posterior electrode pairs for left and right hemispheres was computed. Developmental trajectories for Lateralization of intra-hemispheric coherence were significantly different in HRA and LRC infants: by 12-months HRA infants showed significantly greater leftward Lateralization compared to LRC infants who showed rightward Lateralization. Preliminary results indicate that infants who later met criteria for ASD were those that showed the greatest leftward Lateralization. HRA infants demonstrate an aberrant pattern of leftward Lateralization of intra-hemispheric coherence by the end of the first year of life, suggesting that the network specialized for face processing may develop atypically. Further, infants with the greatest leftward asymmetry at 12-months where those that later met criteria for ASD, providing support to the growing body of evidence that atypical hemispheric specialization may be an early neurobiological marker for ASD.
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atypical Lateralization of erp response to native and non native speech in infants at risk for autism spectrum disorder
Developmental Cognitive Neuroscience, 2013Co-Authors: Anne M Seery, Vanessa Vogelfarley, Charles A Nelson, Helen TagerflusbergAbstract:Language impairment is common in autism spectrum disorders (ASD) and is often accompanied by atypical neural Lateralization. However, it is unclear when in development language impairment or atypical Lateralization first emerges. To address these questions, we recorded event-related-potentials (ERPs) to native and non-native speech contrasts longitudinally in infants at risk for ASD (HRA) over the first year of life to determine whether atypical Lateralization is present as an endophenotype early in development and whether these infants show delay in a very basic precursor of language acquisition: phonemic perceptual narrowing. ERP response for the HRA group to a non-native speech contrast revealed a trajectory of perceptual narrowing similar to a group of low-risk controls (LRC), suggesting that phonemic perceptual narrowing does not appear to be delayed in these high-risk infants. In contrast there were significant group differences in the development of lateralized ERP response to speech: between 6 and 12 months the LRC group displayed a lateralized response to the speech sounds, while the HRA group failed to display this pattern. We suggest the possibility that atypical Lateralization to speech may be an ASD endophenotype over the first year of life.
