Action observation in infancy: Implications for neuro-rehabilitation

© 2016 Mac Keith Press.Action observation therapy has been found to be effective in improving hand motor function in both adults with stroke and children with unilateral cerebral palsy. We here propose a provocative hypothesis arguing that the same therapy might be effective in very early intervention in infants with unilateral or asymmetric brain damage, but through a different underlying mechanism. If the activation of motor networks induced in infancy by action observation enhances the excitability of the damaged sensorimotor cortex, it could also accelerate the maturation of the corticospinal tract and the adaptive shaping of the spinal motor circuits. This hypothesis should be explored carefully in prospective studies and, if confirmed, might support the use of action observation therapy at a much earlier time than experimented so far. What this paper adds: A revision of the literature on AOT in children and adults with unilateral brain damage. The discussion of possible mechanisms of AOT in brain damaged individuals, when applied in early infancy

Development, and construct validity and internal consistency of the Grasp and Reach Assessment of Brisbane (GRAB) for infants with asymmetric brain injury

© 2016 Elsevier Inc. Introduction Infants with asymmetric brain injury (asymBI) are at high risk of Unilateral Cerebral Palsy (UCP). The Grasp and Reach Assessment of Brisbane (GRAB) was developed to detect asymmetries in unimanual/bimanual upper limb (UL) reach and grasp behaviours in infants with asymBI. This study reports the development of the GRAB and evaluates its construct validity and internal consistency. Material and methods Prospective study of twenty four infants with asymBI and twenty typically developing (TD) infants at 18 weeks corrected age (C.A.) in a structured play session. Three different coloured toys were presented at the midline in a block design of six 30-s trials of toy presentation, separated by five 30-s trials of no toy presentation. The number and duration of: (i) unimanual contacts; (ii) unimanual grasps; (iii) bimanual midline grasps; and (iv) duration of other unimanual behaviours (e.g. prehensile movements and transport phase) were measured. An Asymmetry Index (AI) was calculated to determine asymmetries between ULs. Possible AI values ranged from 0 to 100%, indicating proportion of toy presentation time that unimanual behaviours were asymmetric between ULs. Internal consistency of both the Time Phase (TP) and Toy Colour Phase (TCP) test items were determined by calculating Cronbach's alpha coefficients. Each assessment occasion was split into six TPs and two TCPs; whereby one TP comprised one 30-s trial of one toy presentation and one TCP comprised two 30-s trials of the same toy presentation. Results For TP, seven out of nine unimanual behaviours and two out of three bimanual behaviours demonstrated strong internal consistency (Cronbach's alpha coefficients 0.72–0.89). No unimanual activity demonstrated the strongest IC (0.89). For TCP, six out of nine unimanual behaviours demonstrated strong IC (0.73–0.82). Number of unimanual contacts and duration of unimanual prehensile movements demonstrated the strongest IC (0.82). Duration of unimanual contribution to hands at midline and duration of bimanual midline behaviour demonstrated the weakest IC for both TP and TCP (0.46–0.50). For unimanual contacts, the asymBI group were more asymmetric between ULs (mean AI = 50%) compared to the TD group (mean AI = 30%). For unimanual grasps, both groups were similarly asymmetric (both mean AI = 40%). The TD group were almost twice as likely to demonstrate bimanual grasps as the asymBI group (incidence rate ratio IRR 1.9, 95% CI 1.4 to 2.5, p < 0.001). Infants with asymBI were less likely to use the impaired UL compared to the unimpaired UL for grasping (IRR 0.6, 95% CI 0.5 to 0.8, p < 0.001); and used the impaired UL for a shorter proportion of time compared to the unimpaired UL for grasping (mean difference -9.1%, 95% CI -16.6 to -1.7, p = 0.02). Conclusions The GRAB is a criterion-referenced research measure that detects and quantifies the presence or absence of unimanual and bimanual reach and grasp behaviours at 18 weeks C.A. in infants at risk of UCP. The GRAB demonstrated moderate to strong construct validity and strong IC within an assessment occasion. There was no toy preference or warm-up effect for TP or TCP for either group; confirming that the GRAB is a consistent measure across toy presentations within an assessment occasion. In this study, the GRAB identified that infants with asymBI demonstrated a paucity of bimanual grasping compared to TD infants; and demonstrated asymmetric unimanual grasping between ULs at 18 weeks C.A

Upper limb children action-observation training (UP-CAT) study: design of a randomised clinical trial for children with hemiplegia

Objective: The purpose of the present study was to design and test a Randomised Clinical Trial (RCT) for evaluating the efficacy of action-observation therapy in improving the upper limb (UL) activity in children with hemiplegia. Background: Rehabilitation for children with hemiplegia to improve function in the impaired UL uses a wide range of intervention programs; researches using adequately powered RCTs, rigorous methodology and valid outcome measures are essential, to provide the highest level support of therapy effectiveness. Design/Methods: The trial was designed according to Consolidated Standards of Reporting Trials (CONSORT) Statement. It was a randomised, evaluator-blinded, matchpair group trial. Children were randomised within pairs to either experimental or control group. The experimental group performed an Action–Observation Therapy based on watching video sequences of goal actions, chosen according to their UL functional level, combined with motor training with their hemiplegic UL. The control group performed the same tailored actions after watching computer games. A carefully revision of psychometric properties (e.g. small detectable differences) of UL outcome measures for hemiplegic children was performed. Assisting Hand Assessment was chosen as primary measure and based on its power calculation a sample size of 12 matched pairs was established. Moreover, Melbourne and ABILHAND-Kids were included as secondary measures. The time line of assessments was T0 (on the week preceding the onset of the treatment), T1 and T2 (on the week and 8 weeks after the end of the treatment, respectively). Results: We were able to perform children recruitment and testing in the 24 consecutive children according to above experimental planning. The two experimental and control groups differ only for the type of observation but the performed actions were similar so that the changes induced by observation should be measured. Conclusions: To provide reliable results of program rehabilitation effectiveness it is essential to design RCT studies according to CONSORT guidelines

Rehabilitation and neuroplasticity in children with unilateral cerebral palsy

Cerebral palsy is a childhood-onset, lifelong neurological disorder that primarily impairs motor function. Unilateral cerebral palsy (UCP), which impairs use of one hand and perturbs bimanual co-ordination, is the most common form of the condition. The main contemporary upper limb rehabilitation strategies for UCP are constraint-induced movement therapy and bimanual intensive therapy. In this Review, we outline the factors that are crucial to the success of motor rehabilitation in children with UCP, including the dose of training, the relevance of training to daily life, the suitability of training to the age and goals of the child, and the ability of the child to maintain close attention to the tasks. Emerging evidence suggests that the first 2 years of life are a critical period during which interventions for UCP could be more effective than in later life. Abnormal brain organization in UCP, and the effects of development on rehabilitation, must also be understood to develop new effective interventions. Therefore, we also consider neuroimaging methods that can provide insight into the neurobiology of UCP and how the condition responds to existing therapies. We discuss how these methods could shape future rehabilitative strategies based on the neurobiology of UCP and the therapy-induced changes seen in the brain

Proposal for an MRPC system with high-precision timing in the LVD structure

The purpose of this paper is to present a project in order to verify -without the need of knowing the distance CERN-Gran Sasso- the discovery made by the OPERA Collaboration concerning the speed of the CERN neutrinos. The project consists of two parts. A simple one and a less simple one. Both have the great advantage of being totally independent of the knowledge of the distance, ≃ 732 km, between the two Labs, CERN and LNGS, where the neutrinos are produced and detected, respectively. The "simple" version of this project is based on the high-energy horizontal cosmic muons, which traverse LVD and OPERA detectors, thus allowing to cross-calibrate the timing systems of both experiments in a way which is totally independent of the TOF measurements of CNGS. This component of the project is being studied in collaboration with the OPERA group, as the time stabilities of both experiments are needed. In fact it is since a long time that the two groups are engaged with this problem. In this paper we will present and discuss the "less simple" part which allows to establish, at the highest possible level of accuracy, if (v > c) effects really exist. © Società Italiana di Fisica/Springer-Verlag 2012

Proposal for an MRPC system with high-precision timing in the LVD structure

The purpose of this paper is to present a project in order to verify -without the need of knowing the distance CERN-Gran Sasso- the discovery made by the OPERA Collaboration concerning the speed of the CERN neutrinos. The project consists of two parts. A simple one and a less simple one. Both have the great advantage of being totally independent of the knowledge of the distance, ≃ 732 km, between the two Labs, CERN and LNGS, where the neutrinos are produced and detected, respectively. The "simple" version of this project is based on the high-energy horizontal cosmic muons, which traverse LVD and OPERA detectors, thus allowing to cross-calibrate the timing systems of both experiments in a way which is totally independent of the TOF measurements of CNGS. This component of the project is being studied in collaboration with the OPERA group, as the time stabilities of both experiments are needed. In fact it is since a long time that the two groups are engaged with this problem. In this paper we will present and discuss the "less simple" part which allows to establish, at the highest possible level of accuracy, if (v > c) effects really exist