Neurorehabilitation and Recovery Research

SENSe & IN_TOUCH NEWSLETTER

Download the previous newsletters.

1. January 2006 2006 January newletter.pdf

 

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Mechanisms of recovery after stroke: Brain Adaptation associated with Recovery of Motor and Sensory Functions after Stroke

IN_Touch: Imaging Neuroplasticity of Touch

Brain adaptation associated with spontaneous and training-induced recovery of touch sensation post stroke Carey LM, Abbott DF, Puce, A, Seitz, R.

Brain networks may reorganise to optimise stroke recovery. However, little is known about brain mechanisms underlying spontaneous and training-induced recovery post-stroke, particularly following loss of body sensations. We aim to locate and compare areas of brain activation associated with spontaneous and training-induced recovery of touch sensation following stroke, using serial functional magnetic resonance imaging (fMRI).

Thirty stroke patients with impaired touch discrimination of the upper limb, and 12 healthy control participants will be recruited. Study 1 is an observational study, where we will study the relationship between brain activation and touch sensation during the 6 month interval of spontaneous recovery post-stroke. In study 2, we will investigate changes in brain activation associated with training-induced recovery.

Novel information of the relationship between stroke recovery, brain adaptation and the specific experiences that may influence recovery will provide direction for the development and testing of scientific-based interventions designed to maximise recovery by driving and shaping neural reorganisation.

  

Cerebral reorganisation: Motor recovery after stroke

Carey LM Donnan GA Jackson GD Abbott DF

The purpose of these studies were primarily to:

• examine the functional neuroanatomy associated with performance of a simple motor task in older healthy volunteers using Positron Emission Tomography (PET) and functional Magnetic Resonance Imaging (fMRI);
  
• establish the consistency of brain activation over time in a group of older healthy voluntees during performance of a simple movement task;
• identify changes in brain activity associated with recovery of movement over a six-month interval following stroke.

  

Findings from these studies are reported in:
Carey, L.M., Abbott, D.F., Egan, G.F., O’Keefe, G.J., Jackson, G.D., Bernhardt, J., Donnan, G.A. (2006) Evolution of brain activation with good and poor motor recovery after stroke. Neurorehabilitation and Neural Repair. 20:1-18.

Carey, L.M. (2006). Loss of somatic sensation. In Selzer, M.., Clarke, S., Cohen, L., Duncan, P., Gage, F.H. (eds). Textbook of Neural Repair and Rehabilitation. Vol II. Cambridge: Cambridge University Press. (Chapter II.16, pages 231-247).

Carey, L.M., Abbott, D.F., Egan, G.F., Bernhardt, J., Donnan, G.A. (2005). Motor impairment and recovery in the upper limb after stroke: behavioral and neuroanatomical correlates. Stroke 36:625-629.

Brodtman, A, Darby, D. & Carey, L. (2003). Functional MRI and stroke. In Davis , S., Fisher, M & Warach, S (eds). Magnetic Resonance Imaging and Stroke. Cambridge University Press , UK . pp 251-262.

Carey, L.M., Abbott, D.F., Puce, A., Jackson , G.D., Syngeniotis, A., Donnan, G.A. (2002). Re-emergence of activation with post-stroke somatosensory recovery: a serial fMRI case study. Neurology 59:749-752.

Carey, L.M., Abbott, D.F., Egan, G.F., Tochon-Danguy, H.J. & Donnan, G.A.  (2000). The functional neuroanatomy and long term reproducibility of brain activations associated with a simple finger tapping task in older healthy volunteers: a serial PET study. NeuroImage 11: 124-144. 

Macdonell, R., Jackson, G., Curatolo, J., Abbott, D., Berkovic, S., Carey, L., Syngeniotis, A., Fabinyi, G., & Scheffer, I. (1999)  Motor cortex localisation using fMRI and transcranial magnetic stimulation. Neurology, 53: 1462-1467.

Email Leeanne Carey

A brain activation study of limb position sense in stroke affected individuals - with and without sensory training, and in healthy aged

Ettie Ben-Shabat, PhD Candidate, School of Occupational Therapy, and School of Psychological Sciences at La Trobe University

Supervisors: Professor Leeanne Carey, A/Prof Thomas Matyas, Dr Amy Brodtmann

Background: Position sense is decreased in about 40% of stroke sufferers. Such sensory loss detrimentally affects functional outcomes even when the motor capacity is intact. Understanding of central mechanisms (brain activation) of position sense is currently limited. Aim: To better understand how position sense is processed in healthy brains, and how stroke affects patterns of brain activation associated with position sense. Methods: Functional Magnetic Resonance Imaging (fMRI) will be used to study areas of brain activation. During scans subjects will perform wrist position tasks with varying degrees of attention. Benefits: Knowledge gained will advance our understanding of the relationship between proprioceptive loss and brain activation and provide the scientific background for developing new treatment techniques. 

Email Ettie Ben-Shabat

 

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Restorative approaches to Rehabilitation

SENSe: Study of the Effectiveness of Neurorehabilitation on Sensation

Effectiveness of training somatosensation in the hand after stroke: A randomized controlled trial Carey LM, Matyas TA, Macdonell R, Wade D

The aim of this study is to establish the evidence required to recommend the introduction of a new scientifically-based and clinically-focussed sensory discrimination training program into routine clinical practice. We predict improvement in texture discrimination, limb position sense, tactual object recognition and hand function following Stimulus Generalization Training (SGT) compared to exposure alone, between groups (H1) and within individuals (H2). Improvements will be of a clinically significant magnitude (H3), will be maintained at 6-week and 6-month follow-ups (H4) and will be applicable for patients with varying background characteristics (H5).

  

Training Texture Discrimination Impaired by Stroke: Transfer of Training to Novel Stimuli within the Same Modality

Carey LM, Matyas TA

Task-specific learning typifies perceptual training but limits rehabilitation of sensory deficit after stroke. We therefore investigated spontaneous and procedurally facilitated transfer of training effects within the somatosensory domain following stroke. Ten single-case, multiple-baseline experiments were conducted with stroke participants who had impaired discrimination of touch or limb position sense. Our findings demonstrate generalization of training within a somatosensory modality post-stroke, provided a program designed to enhance transfer is used. This has implication for the design of efficient rehabilitation programs.

Findings from these studies are reported in:
Carey, L.M. (2006). Loss of somatic sensation. In  Selzer, M.., Clarke, S., Cohen, L., Duncan, P., Gage, F.H. (eds). Textbook of Neural Repair and Rehabilitation. Vol II. Cambridge: Cambridge University Press. (Chapter II.16, pages 231-247).

Carey, L.M., Matyas, T.A. (2005). Training of somatosensory discrimination after stroke: Facilitation of stimulus generalization. American Journal of Physical Medicine and Rehabilitation. 84(6):428-442.

Carey, L. M.  (1995). Somatosensory loss after stroke. Critical Reviews in Physical & Rehabilitation Medicine, 7, 51-91.

Carey, L. M., Matyas, T. A., & Oke, L. E.  (1993).  Sensory loss in stroke patients: Effective tactile and proprioceptive discrimination training.  Archives of Physical Medicine and Rehabilitation, 74, 602-611.

Carey, L.M., Matyas, T.A., Macdonell, R. & Wade, D (2006). SENSe: Study of the Effectiveness of Neurorehabilitation on Sensation after stroke. 14th International Congress of the World Federation of Occupational Therapists. Sydney, Australia 23-28 July.

Influence of Touch Sensation and its Retraining on Finger Grip after Stroke

Carey LM, Matyas TA

This project investigates the relationship between touch deficit and performance of the basic pinch-grip lift-and-hold action. Quantitative measures of these abilities have been developed. The study also examines the ability to retrain discrimination of how slippery surfaces are and if such retraining can reduce abnormalities in the pinch grip action.

An evaluation of occupational therapy and modified constraint induced movement therapy following Botulinum toxin-A injection in the upper limb in children with spastic hemiplegic cerebral palsy

Brian Hoare, PhD student, School of Occupational Therapy, LaTrobe University
Supervisors: Prof Leeanne Carey, Ms Christine Imms

The randomised controlled trial used in this study is the first of its kind to evaluate the effects of two different interventions following injection of BtA in the upper limb in children with CP.  The objective of the trial is to compare the use of BtA injections and modified constraint induced movement therapy (CIMT) with BtA injections and conventional occupational therapy (OT) to determine which treatment package has the greatest effect on improving the usefulness of the affected arm in bimanual activities.

Email Brian Hoare

Individual patient characteristics that predict favourable outcomes following a generalised somatosensory discrimination training program in the hand after stroke

Johanne Walker, Master of Occupational Therapy Student at La Trobe University
Supervisors: Professor Leeanne Carey

The study will investigate the known characteristics of individuals that may predict success, following sensory discrimination training in the hand after stroke.  The study is being conducted as part of a randomised controlled trial testing the effectiveness of sensory training ie SENSe. It will provide evidence for the selection of stroke patients likely to benefit from sensory training.

Email Johanne Walker

An occupation based approach to sensory retraining post stroke

Mary Mastos, Master of Occupational Therapy Student at La Trobe University
Supervisors: Professor Leeanne Carey

This study aims to investigate the client centred occupational outcomes related to the SENSe retraining program, as compared with a goal directed occupation based approach that incorporates the generalized discrimination principles.

Email Mary Mastos

Progression through sensory retraining: To what extent do individual differences in progress predict formal outcomes?

Megan Turville, Honours Student, Occupational Therapy at La Trobe University
Supervisors: Professor Leeanne Carey

The primary purpose of this study was to explore the relationship between progress through treatment and formal assessment outcomes within a generalised sensory retraining program (SGT) involving people with stroke. This research is being conducted within the Study of the Effectiveness of Neurorehabiliation on Sensation (SENSe). Additional aims of this study were: (1) To investigate whether individuals’ level of training progress provides an accurate prediction of future assessment results; (2) To determine whether the formal outcome measures of this treatment program adequately represent learning and gains observed during intervention; and (3) To identify specific factors within individuals that may influence this relationship.

 

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Nature of Impairment and Impact on Function

Development of quantitative measures of sensation and upper limb function

This project involves a series of studies to develop quantitative measures of touch discrimination, limb position sense and tactual object recognition. Studies include establishing the reliability, discriminative validity and normative standards for the measures. Investigation of the specificity of loss across measures is also being conducted.

Some examples of tests developed or in the process of development include:

• Tactile Discrimination Test (TDT)
• Wrist Position Sense Test (WPST)
• Functional Tactual Object Recognition Test (fTORT)
• Multijoint Arm Position Sense Test (MAPS)

Findings from these studies are reported in:
Carey, L.M., Matyas, T.A. & Oke, L.E.(2002). Evaluation of impaired fingertip texture discrimination and wrist position sense in patients affected by stroke: Comparison of clinical and new quantitative measures. Journal of Hand Therapy 15: 71-82.

Carey, L. M., Oke, L. & Matyas, T. A.  (1997).  Impaired touch discrimination after stroke: A quantitative test. Journal of Neurologic Rehabilitation, 11,219-232.

Carey, L. M., Oke, L. & Matyas, T. A.  (1996).  Impaired limb position sense after  stroke: A quantitative test for clinical use. Archives of Physical Medicine & Rehabilitation, 77, 1271-8.

Carey, L. M.  (1995).  Somatosensory loss after stroke. Critical Reviews in Physical & Rehabilitation Medicine, 7, 51-91.

The Contribution of Somatosensory Impairment to Pinch Grip Ability after Stroke

Jannette Blennerhassett, PhD candidate, Schools of Occupational Therapy and Psychological Sciences, LaTrobe University
Supervisors: Prof Leeanne Carey and Assoc/Prof Thomas Matyas

Altered ability to grip and lift objects is a major problem following stroke. Lack of controlled evidence about the characteristics and underlying mechanisms limit effective management of this problem. The aims of this thesis were to:

1. characterise impairment on a controlled Pinch Grip Lift and Hold (PGLH) task when guided by somatosensory input, and
2. investigate the relative contribution of two key somatosensory deficits to PGLH impairment post-stroke after controlling for coexisting motor deficit.

The findings highlight that somatosensory processing of friction between the skin and object should be integrated into training ability to grip and lift objects following stroke.

Blennerhassett, J.M., Carey, L.M., Matyas, T.A. (2006). Grip Force Regulation During Pinch Grip Lifts Under Somatosensory Guidance: Comparison Between People With Stroke and Healthy Controls. Archives of Physical Medicine and Rehabilitation. 87(3)418-429.

Email Jannette Blennerhassett

Further development of 'The Melbourne Assessment of Unilateral Upper Limb Function' (the Melbourne Assessment)

Melinda Randall, PhD Candidate, Occupational Therapy at La Trobe University
Supervisors: Professor Leeanne Carey, Ms Christine Imms

The Melbourne Assessment was developed in the 1990's to measure quality of upper limb movement in children aged 5 to 15 years with cerebral palsy. This project addresses the further development of this tool in the following two ways.

1. Development and validation of an adapted form of the assessment for use with children aged 2 to 4 years. This study involves reviewing and modifying the assessment, then trialing the modified version with 60 children aged 2 to 4 years. Two samples of children will be trialed, (i) 30 who have no known neurological impairment and (ii) 30 who have a congenital or acquired neurological impairment.
2. Further investigation of the construct validity of the tool by (i) analysing sub-items to confirm and/or refine items for inclusion in the assessment and refine scaling units utilised and (ii) establishing empirical evidence for the dimensionality of the assessment items.

Email Melinda Randall

Normative standard for the Multi-joint assessment of position sense in the upper limb

Eickmeyer, T. Masters-coursework candidate, School of Occupatienal Therapy, La Trobe University
Supervisors: Professor Leeanne Carey

The Multijoint Arm Position Sense test has been recently developed by Carey and colleagues. This study furthers test development by providing normative data for the test. Normative data was collected on 32 neurologically unimpaired adults aged 45 to 84 years. The findings provide quantitative standards to facilitate interpretation of scores in individuals who have experienced stroke.

Discriminative validity of the new mutli-joint test of limb position sense for use with stroke clients

Kunshan Goh, Honours Student, Occupational Therapy at La Trobe University
Supervisors: Professor Leeanne Carey

This study aims to: 1.) Determine ability of the Multijoint Arm Position Sense (MAPS) test to discriminate impaired performance after stroke, relative to age matched normal performance and 2) Investigate the relationship between performance on individual joint tests of limb position in the upper limb and the MAPS test, in a sample of stroke participants. Evidence established will support the use of the Multi-joint test in clinical practice.

 

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Recently Completed Theses

Neilson, C. 2004. Investigation of the effectiveness of context-embedded task training in upper limb rehabilitation after stroke. Masters-coursework

Nankervis, J. 2004. Normative standards for the functional Test of Tactual Object Recognition. Honours