| 1. |
- Andrew, Churchill, et al.
(författare)
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Vision of the hand and environmental context in human prehension
- 2000
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Ingår i: Experimental Brain Research. - : Springer Science and Business Media LLC. - 0014-4819 .- 1432-1106. ; 134:1, s. 81-89
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Tidskriftsartikel (refereegranskat)abstract
- Previous findings on the role of visual contact with the hand in the control of reaching and grasping have been contradictory. Some studies have shown that such contact is largely irrelevant, while more recent ones have emphasised its importance. In contrast, information arising from the surrounding environment has received relatively little attention in the study of prehensile actions. In order to identify the roles of both sources of information, we made kinematic comparisons between three conditions. In the first, reaching was performed in a dimly lit room and compared with a second condition in which reaches in the dark, but with the thumb and first finger illuminated, were made to a luminous object. This contrast allows the effects of environmental context to be identified. A comparison between the second and a third condition, in which both vision of the hand and the environment was removed, but the object was still visually available, enabled the assessment of how and when vision of the hand plays a role. Removing environmental cues had effects both early and late in the reach, while vision of the hand was only crucial in the period after peak deceleration. In addition, removal of both sources of information resulted in larger grip apertures. Differences and similarities between our findings and those of other studies are discussed, as is the ongoing debate about the relative importance of visual feedback of the hand in the control and co-ordination of prehensile actions. We conclude with suggestions for further research based on the set-up used in the present study.
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| 2. |
- Blaszczyk, Izabela, 1967-
(författare)
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Upper limb assessment and treatment in cerebral palsy
- 2023
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Cerebral palsy (CP) is a heterogeneous group of neurological disorders caused by fetal or infant brain damage that often involves deficits in upper limb (UL) posture and function. Knowledge about effective methods of assessment and treatment of UL in CP is not extensive. In this thesis, different aspects of these two are explored.In Paper I we retrospectively investigated the effect of a long-term treatment regime developed in Västerbotten county habilitation service. The treatment regime included intramuscular injections of botulinum toxin type A (BoNT-A) combined with occupational therapy (OT) and movement training. The results of passive extension of the wrist with fingers extended and the assessment of hand function in children with severe hand function impairment (initially House functional classification 0-1) were analyzed over time. Twenty-five children were divided into 3 groups depending on the treatment regime start age (before or after the age of 7) and treatment regime availability. We found significantly worse passive extension of the wrist with fingers extended in children who did not have a chance to benefit from therapy in early childhood. Additionally, an improvement in the passive movement of the wrists was noted in children who completed the treatment regime before the age of 7. Regarding hand function, a significant difference was found between children who received treatment in early childhood and those who received treatment as adolescents.The injections of BoNT-A in CP are common, however the monitoring of eventual side effects and adverse events (AEs) after this treatment is difficult to perform in clinical practice. To facilitate this process, we created a new, no previously validated questionnaire (Paper II). The questionnaire was given to patients or their caregivers to be completed after each BoNT-A treatment. 94% of participants returned the questionnaire. 80 % were filled in completely which proves the effectiveness of the applied form and the ease of its use in clinical practice. 61% of patients reported one or more different AEs or sides effects. In addition, we analyzed the risk for generalized and focal distal AEs reported by 38% of patients. Those may indicate the spread of BoNT-A toxin to the whole body, therefore requiring special attention. We found that females had a 1.899 relative risk with significant association (p=0.029) of reporting generalized and focal delayed AEs compared to males. The use of the questionnaire helped to make the decision to change or discontinue BoNT-A injections in 8 cases (11%).In some patients with dyskinetic type of CP (DCP) treated with BoNT-A to diminish the external rotation posture of the shoulders, a loss of treatment effect was observed, which contributed to the need to look for another method of treatment. In paper III, a surgical method to manage the external rotation posture of the shoulders is presented. The surgical procedure consists of weakening the strength of the externally rotating muscles by cutting the attachment of one of them (release of the posterior deltoid) and complete denervation of the other (denervation of the infraspinatus). The third shoulder external rotator (teres minor) remains intact. The results of this procedure performed in 7 shoulders in 6 patients (age 14-24) were analyzed using satisfaction questionnaire and pre-/postoperative video-recordings. Five of 6 patients were very satisfied with the treatment, one was neither satisfied nor dissatisfied. Four patients had an obvious improvement in their shoulder position confirmed on video recordings. In one, overcorrection in the form of internal shoulder rotation was observed.Assessment of the thumb in CP is important as the thumb impairment plays a crucial role in hand grip function. Paper IV presents a new tool called CP-thumb score, which addresses the occupational therapists to follow the changes in the thumb function and its posture. CP-thumb score has two parts: descriptive and score of the thumb’s CMC joint radial abduction. Thirty thumbs in 19 patients with all types of CP were assessed with CP-thumb score. All assessments were made based on available video recordings. Additionally, all thumbs were assessed using the House’s thumb-in-palm classification which has been shown to be unreliable. These two thumb assessments were compared with each other.
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| 3. |
- Bäckström, Anna, et al.
(författare)
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Action planning in relation to movement performance in 6-year-old children with autism spectrum disorder
- 2019
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Konferensbidrag (refereegranskat)abstract
- Introduction: Recent research proposes problems with action planning as part of atypical motor functioning in children with autism spectrum disorder (ASD), although findings are inconsistent. This study investigated relations between action planning and movement performance in 6-year-old children with and without ASD.Patients and methods: 3D kinematic recordings of preferred arm/hand performance on a sequential peg rotation task with varying complexity of goal insertion (four endpoints and either visual or occluded goal display at onset) were conducted in 6 children with ASD (MAge = 6.4) and 6 typically developing (TD) controls (MAge = 6.5).Results: Analyses revealed significant (p < .05) group and task-endpoint differences for movement segmentation (number of movement units, MUs) and 3D movement distance. Children with ASD generally displayed more MUs and longer distances than controls and all children showed increased MUs and movement distance on more complex task-endpoints. TD controls showed significantly shorter movement initiation latency (MIL) durations than ASD in the visual condition and evidently longer MILs in the occluded than visual condition. In contrast, no difference between goal display conditions was shown for the ASD group.Conclusion: Children with ASD generally had longer movement distances and more segmented movements than controls, suggesting less efficient movement performance. Movement performance was not evidently affected by goal display condition in either group. However, the lack of MIL differences between goal display conditions within the ASD group indicates reduced pre-planning, possibly affecting movement execution efficiency.
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| 4. |
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| 5. |
- Bäckström, Anna, et al.
(författare)
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Atypical motor planning in an interpersonal context in 9-year-old children with autism spectrum disorder (ASD)
- 2023
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Ingår i: 35th EACD Annual meeting European Academy of Childhood Disability. - : European Academy of Childhood Disability. ; , s. 254-254
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Konferensbidrag (refereegranskat)abstract
- Introduction: Motor planning deviances may negatively affect interpersonal motor interactions in ASD, although detailed studies are sparse. This study examined motor planning kinematics in an interpersonal and non-interpersonal context in 9-year-old children with ASD and neurotypical peers.Patients and methods: Twelve children with ASD and 17 controls performed two different sequential manual tasks (preferred hand): grasping and placing a peg on a wooden disc (non-interpersonal) or in the hand of an examiner (interpersonal). Three-dimensional kinematic recordings of arm/hand movements were performed. Group and task differences were explored for total movement duration (MD), and for peak velocity (PV) and placement of peak velocity (PPV) during reach-to-grasp and transport-to-place movements, respectively.Results: Task differences were found in terms of longer MD and higher transport-to-place-PV in the disc- compared to hand-task. An interaction effect was evident for reach-to-grasp-PPV, where the control-group, but not ASD, had earlier reach-to-grasp-PPV and longer relative deceleration in the hand-task compared to the disc-task.Conclusion: Results show that the interpersonal context influenced initial reach-to-grasp motor planning in the control-group, but not the ASD-group. Later in the sequential movement (transport-to-place), the interpersonal context seemed to influence motor planning independent of group. Taken together, this indicates support towards a more careful peg-placing in the interpersonal hand-task in the control-group but much less clearly so in the ASD-group.Relevance for users and families: Atypical motor planning may influence motor interaction with peers. Investigations of motor planning and movement organization in ASD could thus inform interventions also targeting interpersonal exchange.
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| 6. |
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| 7. |
- Bäckström, Anna, et al.
(författare)
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Motor imagery ability in 7-year-old children with autism spectrum disorder
- 2020
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Konferensbidrag (övrigt vetenskapligt/konstnärligt)abstract
- Introduction: Knowledge about motor imagery (MI) ability in autism spectrum disorder (ASD) is limited and inconclusive in young children with ASD. The aim of the current study was to investigate MI ability in 7-year-old children with ASD.Patients and methods: Thirteen children with ASD and 13 typically developing (TD) children performed a computerized hand laterality judgement task (HLJ) and a non-corporeal visual imagery (VI) control task. All participants passing a criterion test performed the tasks with images at 4 different rotational increments to vary the MI biomechanical demands (HLJ task) or VI angle rotational demands (VI task). Response times (RT) and accuracy were extracted.Results: Four children with ASD did not pass the HLJ criterion test and one failed the VI criterion test. The ASD-group had evidently more incorrect responses than TD on both tasks. Analyses of RT showed a biomechanical effect in the MI task and an angle increment effect in the VI task in both groups. Children with ASD had longer RT than TD children on VI but not MI tasks. Conclusion: Findings suggest that both the ASD and control children used MI to solve the HLJ task. However, failures to pass the HLJ criterion test and the increased error rate in the ASD group indicate that MI ability is weaker in young children with autism than TD controls. Notably, a large individual variability in employment of MI within the ASD group was found, ranging from functional, fractional but existing, to absent MI ability.
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| 8. |
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| 9. |
- Bäckström, Anna, et al.
(författare)
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Motor planning and movement execution during goal-directed sequential manual movements in 6-year-old children with autism spectrum disorder : A kinematic analysis
- 2021
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Ingår i: Research in Developmental Disabilities. - : Elsevier. - 0891-4222 .- 1873-3379. ; 115
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Tidskriftsartikel (refereegranskat)abstract
- Background: Atypical motor functioning is prevalent in children with autism spectrum disorder (ASD). Knowledge of the underlying kinematic properties of these problems is sparse.Aims: To investigate characteristics of manual motor planning and performance difficulties/diversity in children with ASD by detailed kinematic measurements. Further, associations between movement parameters and cognitive functions were explored.Methods and procedures: Six-year-old children with ASD (N = 12) and typically developing (TD) peers (N = 12) performed a sequential manual task comprising grasping and fitting a semi-circular peg into a goal-slot. The goal-slot orientation was manipulated to impose different motor planning constraints. Movements were recorded by an optoelectronic system.Outcomes and results: The ASD-group displayed less efficient motor planning than the TD-group, evident in the reach-to-grasp and transport kinematics and less proactive adjustments of the peg to the goal-slot orientations. The intra-individual variation of movement kinematics was higher in the ASD-group compared to the TD-group. Further, in the ASD-group, movement performance associated negatively with cognitive functions.Conclusions and implications: Planning and execution of sequential manual movements proved challenging for children with ASD, likely contributing to problems in everyday actions. Detailed kinematic investigations contribute to the generation of specific knowledge about the nature of atypical motor performance/diversity in ASD. This is of potential clinical relevance.
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| 10. |
- Bäckström, Anna, et al.
(författare)
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Visuomotor integration in action planning in 7-year-old children with autism spectrum disorder
- 2022
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Ingår i: Specia issue: Abstracts of the 34th annual meeting of the European Academy of Childhood Disability (EACD) Barcelona, Spain 18-21 May 2022. - : Mac Keith Press. ; , s. 65-65
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Konferensbidrag (refereegranskat)abstract
- Introduction: Difficulties with action planning and visuomotor integration may contribute to atypical motorfunctioning in children with autism spectrum disorder (ASD), although detailed studies of sensorimotorintegration in action planning are sparse. This ongoing study investigates visuomotor integration in actionplanning in 7-year-old children with and without ASD.Patients and methods: A sub-sample of 6 children with ASD and 6 typically developing (TD) controls wereincluded. Recordings of gaze synchronized with 3D kinematic registration were made during performance of amanual sequential peg rotation task with variations in goal insertion complexity. Group differences and relations between movement duration and number of gaze shifts over the sequential movement phases(latency, reach-to-grasp, grasp, and transport-to-fit) were explored.Results: No significant group differences were found for either movement duration or number of gaze shifts.When controlling for the between-participants variance, total number of gaze shifts and number of gaze shiftsin reach-to-grasp were related to movement duration in the initial phases of the movement in the TD-group but not in the ASD-group.Conclusion: The results indicate that, whilst performance measures were similar between groups, the overallpattern of visuomotor integration was related to feed-forward movement processes in the sequentialmovement in the TD-group but not in the ASD-group. This finding adds support to previous suggestions thatvisuomotor integration underpinning action planning may operate differently in ASD. Synchronizedexamination of gaze and detailed movement registration appears as a promising methodology for detailed investigation of visuomotor integration in action planning.
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