Subgrouping Autism Based on Symptom Severity Leads to Differences in the Degree of Convergence Between Core Feature Domains / Allison WHITTEN in Journal of Autism and Developmental Disorders, 48-6 (June 2018)  

Public ISBD [article]  inJournal of Autism and Developmental Disorders > 48-6 (June 2018) . - p.1908-1919 Titre : Subgrouping Autism Based on Symptom Severity Leads to Differences in the Degree of Convergence Between Core Feature Domains Type de document : texte imprimé Auteurs : Allison WHITTEN, Auteur ; Kathryn E. UNRUH, Auteur ; Robin L. SHAFER, Auteur ; James W. BODFISH, Auteur Article en page(s) : p.1908-1919 Langues : Anglais (eng) Mots-clés : Autism  Autism core features  Phenotype Index. décimale : PER Périodiques Résumé : Existing models of autism spectrum disorder (ASD) disagree as to whether the core features should be conceptualized as convergent (related) or divergent (unrelated), and the few previous studies addressing this question have found conflicting results. We examined standardized parent ratings of symptoms from three domains (social, communication, repetitive behaviors) in large samples of typically developing children, children with ASD, and ASD subgroups. Our results suggest that the most evidence for divergence lies in typically developing children and lower severity ASD cases, while more evidence for convergence is found in a subset of cases with more severe impairment on any core feature. These results highlight the importance of subgrouping ASD given the degree of phenotypic heterogeneity present across the autism spectrum. En ligne : http://dx.doi.org/10.1007/s10803-017-3451-3 Permalink : https://www.cra-rhone-alpes.org/cid/opac_css/index.php?lvl=notice_display&id=361 [article] Subgrouping Autism Based on Symptom Severity Leads to Differences in the Degree of Convergence Between Core Feature Domains [texte imprimé] / Allison WHITTEN, Auteur ; Kathryn E. UNRUH, Auteur ; Robin L. SHAFER, Auteur ; James W. BODFISH, Auteur . - p.1908-1919. Langues : Anglais (eng) in Journal of Autism and Developmental Disorders > 48-6 (June 2018) . - p.1908-1919 Mots-clés : Autism  Autism core features  Phenotype Index. décimale : PER Périodiques Résumé : Existing models of autism spectrum disorder (ASD) disagree as to whether the core features should be conceptualized as convergent (related) or divergent (unrelated), and the few previous studies addressing this question have found conflicting results. We examined standardized parent ratings of symptoms from three domains (social, communication, repetitive behaviors) in large samples of typically developing children, children with ASD, and ASD subgroups. Our results suggest that the most evidence for divergence lies in typically developing children and lower severity ASD cases, while more evidence for convergence is found in a subset of cases with more severe impairment on any core feature. These results highlight the importance of subgrouping ASD given the degree of phenotypic heterogeneity present across the autism spectrum. En ligne : http://dx.doi.org/10.1007/s10803-017-3451-3 Permalink : https://www.cra-rhone-alpes.org/cid/opac_css/index.php?lvl=notice_display&id=361

Visual and somatosensory feedback mechanisms of precision manual motor control in autism spectrum disorder / Robin L. SHAFER in Journal of Neurodevelopmental Disorders, 13 (2021)  

Public ISBD [article]  inJournal of Neurodevelopmental Disorders > 13 (2021) Titre : Visual and somatosensory feedback mechanisms of precision manual motor control in autism spectrum disorder Type de document : texte imprimé Auteurs : Robin L. SHAFER, Auteur ; Zheng WANG, Auteur ; James BARTOLOTTI, Auteur ; Matthew W. MOSCONI, Auteur Langues : Anglais (eng) Mots-clés : Adolescent  Adult  Autism Spectrum Disorder  Child  Feedback  Hand Strength  Humans  Young Adult  Autism spectrum disorders  Entropy  Fine motor control  Grip force  Proprioception  Sensorimotor  Sensory reweighting  Visual gain Index. décimale : PER Périodiques Résumé : BACKGROUND: Individuals with autism spectrum disorder (ASD) show deficits processing sensory feedback to reactively adjust ongoing motor behaviors. Atypical reliance on visual and somatosensory feedback each have been reported during motor behaviors in ASD suggesting that impairments are not specific to one sensory domain but may instead reflect a deficit in multisensory processing, resulting in reliance on unimodal feedback. The present study tested this hypothesis by examining motor behavior across different visual and somatosensory feedback conditions during a visually guided precision grip force test. METHODS: Participants with ASD (N = 43) and age-matched typically developing (TD) controls (N = 23), ages 10-20 years, completed a test of precision gripping. They pressed on force transducers with their index finger and thumb while receiving visual feedback on a computer screen in the form of a horizontal bar that moved upwards with increased force. They were instructed to press so that the bar reached the level of a static target bar and then to hold their grip force as steadily as possible. Visual feedback was manipulated by changing the gain of the force bar. Somatosensory feedback was manipulated by applying 80 Hz tendon vibration at the wrist to disrupt the somatosensory percept. Force variability (standard deviation) and irregularity (sample entropy) were examined using multilevel linear models. RESULTS: While TD controls showed increased force variability with the tendon vibration on compared to off, individuals with ASD showed similar levels of force variability across tendon vibration conditions. Individuals with ASD showed stronger age-associated reductions in force variability relative to controls across conditions. The ASD group also showed greater age-associated increases in force irregularity relative to controls, especially at higher gain levels and when the tendon vibrator was turned on. CONCLUSIONS: Our findings that disrupting somatosensory feedback did not contribute to changes in force variability or regularity among individuals with ASD suggests a reduced ability to integrate somatosensory feedback information to guide ongoing precision manual motor behavior. We also document stronger age-associated gains in force control in ASD relative to TD suggesting delayed development of multisensory feedback control of motor behavior. En ligne : https://dx.doi.org/10.1186/s11689-021-09381-2 Permalink : https://www.cra-rhone-alpes.org/cid/opac_css/index.php?lvl=notice_display&id=574 [article] Visual and somatosensory feedback mechanisms of precision manual motor control in autism spectrum disorder [texte imprimé] / Robin L. SHAFER, Auteur ; Zheng WANG, Auteur ; James BARTOLOTTI, Auteur ; Matthew W. MOSCONI, Auteur. Langues : Anglais (eng) in Journal of Neurodevelopmental Disorders > 13 (2021) Mots-clés : Adolescent  Adult  Autism Spectrum Disorder  Child  Feedback  Hand Strength  Humans  Young Adult  Autism spectrum disorders  Entropy  Fine motor control  Grip force  Proprioception  Sensorimotor  Sensory reweighting  Visual gain Index. décimale : PER Périodiques Résumé : BACKGROUND: Individuals with autism spectrum disorder (ASD) show deficits processing sensory feedback to reactively adjust ongoing motor behaviors. Atypical reliance on visual and somatosensory feedback each have been reported during motor behaviors in ASD suggesting that impairments are not specific to one sensory domain but may instead reflect a deficit in multisensory processing, resulting in reliance on unimodal feedback. The present study tested this hypothesis by examining motor behavior across different visual and somatosensory feedback conditions during a visually guided precision grip force test. METHODS: Participants with ASD (N = 43) and age-matched typically developing (TD) controls (N = 23), ages 10-20 years, completed a test of precision gripping. They pressed on force transducers with their index finger and thumb while receiving visual feedback on a computer screen in the form of a horizontal bar that moved upwards with increased force. They were instructed to press so that the bar reached the level of a static target bar and then to hold their grip force as steadily as possible. Visual feedback was manipulated by changing the gain of the force bar. Somatosensory feedback was manipulated by applying 80 Hz tendon vibration at the wrist to disrupt the somatosensory percept. Force variability (standard deviation) and irregularity (sample entropy) were examined using multilevel linear models. RESULTS: While TD controls showed increased force variability with the tendon vibration on compared to off, individuals with ASD showed similar levels of force variability across tendon vibration conditions. Individuals with ASD showed stronger age-associated reductions in force variability relative to controls across conditions. The ASD group also showed greater age-associated increases in force irregularity relative to controls, especially at higher gain levels and when the tendon vibrator was turned on. CONCLUSIONS: Our findings that disrupting somatosensory feedback did not contribute to changes in force variability or regularity among individuals with ASD suggests a reduced ability to integrate somatosensory feedback information to guide ongoing precision manual motor behavior. We also document stronger age-associated gains in force control in ASD relative to TD suggesting delayed development of multisensory feedback control of motor behavior. En ligne : https://dx.doi.org/10.1186/s11689-021-09381-2 Permalink : https://www.cra-rhone-alpes.org/cid/opac_css/index.php?lvl=notice_display&id=574

Visual feedback and motor memory contributions to sustained motor control deficits in autism spectrum disorder across childhood and into adulthood / Robin L. SHAFER in Journal of Neurodevelopmental Disorders, 17 (2025)  

Public ISBD [article]  inJournal of Neurodevelopmental Disorders > 17 (2025) Titre : Visual feedback and motor memory contributions to sustained motor control deficits in autism spectrum disorder across childhood and into adulthood Type de document : texte imprimé Auteurs : Robin L. SHAFER, Auteur ; James BARTOLOTTI, Auteur ; Abigail DRIGGERS, Auteur ; Erin BOJANEK, Auteur ; Zheng WANG, Auteur ; Matthew W. MOSCONI, Auteur Langues : Anglais (eng) Mots-clés : Humans  Adolescent  Child  Autism Spectrum Disorder/physiopathology/complications  Male  Young Adult  Feedback, Sensory/physiology  Adult  Female  Psychomotor Performance/physiology  Memory/physiology  Motor Skills/physiology  Hand Strength/physiology  Autism spectrum disorders  Entropy  Fine motor control  Grip force  Motor memory  Sensorimotor  Sensory integration  Visual feedback  Visuomotor  provided written informed consent after a complete description of the study, in  accordance with the Declaration of Helsinki. For participants under the age of 18  and adults who were under legal guardianship, a parent or legal guardian provided  written informed consent on behalf of the participant, and the participant  provided written assent. All study procedures were approved by the University of  Kansas Medical Center Institutional Review Board (IRB#: STUDY00140269). Consent  for publication: Not applicable. Competing interests: MWM is PI on an  investigator initiated clinical trial of behavioral inflexibility in autism  funded by Acadia Pharmaceuticals. MWM and ZW received funding from Novartis  Pharmaceuticals Corporation for an investigator-initiated study of Phelan  McDermid Syndrome. The other authors declare that they have no competing  interests. Index. décimale : PER Périodiques Résumé : BACKGROUND: Autistic individuals show deficits in sustained fine motor control which are associated with an over-reliance on visual feedback. Motor memory deficits also have been reported during sustained fine motor control in autism spectrum disorders (ASD). The development of motor memory and visuomotor feedback processes contributing to sustained motor control issues in ASD are not known. The present study aimed to characterize age-related changes in visual feedback and motor memory processes contributing to sustained fine motor control issues in ASD. METHODS: Fifty-four autistic participants and 31 neurotypical (NT) controls ages 10-25 years completed visually guided and memory guided sustained precision gripping tests by pressing on force sensors with their dominant hand index finger and thumb. For visually guided trials, participants viewed a stationary target bar and a force bar that moved upwards with increased force for 15s. During memory guided trials, the force bar was visible for 3s, after which participants attempted to maintain their force output without visual feedback for another 12s. To assess visual feedback processing, force accuracy, variability (standard deviation), and regularity (sample entropy) were examined. To assess motor memory, force decay latency, slope, and magnitude were examined during epochs without visual feedback. RESULTS: Relative to NT controls, autistic individuals showed a greater magnitude and a trend for a steeper slope of force decay during memory guided trials. Across conditions, the ASD group showed reduced force accuracy (β = 0.41, R(2) = 0.043, t(79.3)=2.36, p = .021) and greater force variability (β=-2.16, R(2) = 0.143, t(77.1)=-4.04, p = .0001) and regularity (β=-0.52, R(2) = 0.021, t(77.4)=-2.21, p = .030) relative to NT controls at younger ages, but these differences normalized by adolescence (age x group interactions). Lower force accuracy and greater force variability during visually guided trials and steeper decay slope during memory guided trials were associated with overall autism severity. CONCLUSIONS: Our findings that autistic individuals show a greater magnitude and tendency for a greater rate of force decay than NT individuals following the removal of visual feedback indicate that motor memory deficits contribute to fine motor control issues in ASD. Findings that sensorimotor differences in ASD were specific to younger ages suggest delayed development across multiple motor control processes. En ligne : https://dx.doi.org/10.1186/s11689-025-09607-7 Permalink : https://www.cra-rhone-alpes.org/cid/opac_css/index.php?lvl=notice_display&id=576 [article] Visual feedback and motor memory contributions to sustained motor control deficits in autism spectrum disorder across childhood and into adulthood [texte imprimé] / Robin L. SHAFER, Auteur ; James BARTOLOTTI, Auteur ; Abigail DRIGGERS, Auteur ; Erin BOJANEK, Auteur ; Zheng WANG, Auteur ; Matthew W. MOSCONI, Auteur. Langues : Anglais (eng) in Journal of Neurodevelopmental Disorders > 17 (2025) Mots-clés : Humans  Adolescent  Child  Autism Spectrum Disorder/physiopathology/complications  Male  Young Adult  Feedback, Sensory/physiology  Adult  Female  Psychomotor Performance/physiology  Memory/physiology  Motor Skills/physiology  Hand Strength/physiology  Autism spectrum disorders  Entropy  Fine motor control  Grip force  Motor memory  Sensorimotor  Sensory integration  Visual feedback  Visuomotor  provided written informed consent after a complete description of the study, in  accordance with the Declaration of Helsinki. For participants under the age of 18  and adults who were under legal guardianship, a parent or legal guardian provided  written informed consent on behalf of the participant, and the participant  provided written assent. All study procedures were approved by the University of  Kansas Medical Center Institutional Review Board (IRB#: STUDY00140269). Consent  for publication: Not applicable. Competing interests: MWM is PI on an  investigator initiated clinical trial of behavioral inflexibility in autism  funded by Acadia Pharmaceuticals. MWM and ZW received funding from Novartis  Pharmaceuticals Corporation for an investigator-initiated study of Phelan  McDermid Syndrome. The other authors declare that they have no competing  interests. Index. décimale : PER Périodiques Résumé : BACKGROUND: Autistic individuals show deficits in sustained fine motor control which are associated with an over-reliance on visual feedback. Motor memory deficits also have been reported during sustained fine motor control in autism spectrum disorders (ASD). The development of motor memory and visuomotor feedback processes contributing to sustained motor control issues in ASD are not known. The present study aimed to characterize age-related changes in visual feedback and motor memory processes contributing to sustained fine motor control issues in ASD. METHODS: Fifty-four autistic participants and 31 neurotypical (NT) controls ages 10-25 years completed visually guided and memory guided sustained precision gripping tests by pressing on force sensors with their dominant hand index finger and thumb. For visually guided trials, participants viewed a stationary target bar and a force bar that moved upwards with increased force for 15s. During memory guided trials, the force bar was visible for 3s, after which participants attempted to maintain their force output without visual feedback for another 12s. To assess visual feedback processing, force accuracy, variability (standard deviation), and regularity (sample entropy) were examined. To assess motor memory, force decay latency, slope, and magnitude were examined during epochs without visual feedback. RESULTS: Relative to NT controls, autistic individuals showed a greater magnitude and a trend for a steeper slope of force decay during memory guided trials. Across conditions, the ASD group showed reduced force accuracy (β = 0.41, R(2) = 0.043, t(79.3)=2.36, p = .021) and greater force variability (β=-2.16, R(2) = 0.143, t(77.1)=-4.04, p = .0001) and regularity (β=-0.52, R(2) = 0.021, t(77.4)=-2.21, p = .030) relative to NT controls at younger ages, but these differences normalized by adolescence (age x group interactions). Lower force accuracy and greater force variability during visually guided trials and steeper decay slope during memory guided trials were associated with overall autism severity. CONCLUSIONS: Our findings that autistic individuals show a greater magnitude and tendency for a greater rate of force decay than NT individuals following the removal of visual feedback indicate that motor memory deficits contribute to fine motor control issues in ASD. Findings that sensorimotor differences in ASD were specific to younger ages suggest delayed development across multiple motor control processes. En ligne : https://dx.doi.org/10.1186/s11689-025-09607-7 Permalink : https://www.cra-rhone-alpes.org/cid/opac_css/index.php?lvl=notice_display&id=576

---

1 (1 - 3 / 3) Par page : 25 50 100 200