Teo W.P., Rodrigues, J.P., Mastaglia, F.L., Thickbroom, G.W. 2014, ‘Modulation of corticomotor excitability after maximal or sustainable-rate repetitive finger movement is impaired in parkinson’s disease and is reversed by levodopa’, Clinical Neurophysiology, 125, 3, pp. 562-568.
Abstract: In healthy subjects, fatiguing exercises induce a period of post-exercise corticomotor depression (PECD) that is absent in Parkinson’s disease (PD). Our objective is to determine the time-course of corticomotor excitability changes following a 10-s repetitive index finger flexion-extension task performed at maximal voluntary rate (MVR) and a slower sustainable rate (MSR) in PD patients OFF and ON levodopa….more
Johnson, L., James, I., Rodrigues, J., Stell, R., Thickbroom, G., Mastaglia, F. 2013, ‘Clinical and posturographic correlates of falling in Parkinson’s disease’, Movement Disorders, 28, 9, pp. 1250-1256.
Abstract: Various clinical tests and balance scales have been used to assess postural stability and the risk of falling in patients with idiopathic Parkinson’s disease (IPD). Quantitative posturography allows a more objective assessment but the findings in previous studies have been inconsistent and few studies have investigated which posturographic measures correlate best with a history of falling. The purpose of this study was to determine the efficacy of clinical tests, balance scales…more
Teo, W.P., Rodrigues, J.P., Mastaglia, F.L., Thickbroom, G.W. 2013, ‘Comparing kinematic changes between a finger-tapping task and unconstrained finger flexion-extension task in patients with Parkinson’s disease’, Experimental Brain Research, 227, 3, pp. 323-331.
Abstract: Repetitive finger tapping is a well-established clinical test for the evaluation of parkinsonian bradykinesia, but few studies have investigated other finger movement modalities. We compared the kinematic changes (movement rate and amplitude) and response to levodopa during a conventional index finger-thumb-tapping task and an unconstrained index finger flexion-extension task performed at maximal voluntary rate (MVR) for 20 s in 11 individuals with levodopa-responsive Parkinson’s…more
Teo, W.P., Rodrigues, J.P., Mastaglia, F.L., Thickbroom, G.W. 2012, ‘Post-exercise depression in corticomotor excitability after dynamic movement: A general property of fatiguing and non-fatiguing exercise’, Experimental Brain Research, 216, 1, pp. 41-49.
Abstract: Transcranial magnetic stimulation has been used to study changes in central excitability associated with motor tasks. Recently, we reported that a finger flexion–extension task performed at a maximal voluntary rate (MVR) could not be sustained and that this was not due to muscle fatigue, but was more likely a breakdown in central…more
Teo, W.P., Rodrigues, J.P., Mastaglia, F.L., Thickbroom, G.W. 2012, ‘Changes in corticomotor excitability and inhibition after exercise are influenced by hand dominance and motor demand’, Neuroscience, 210, pp. 110-117.
Abstract: Previous studies on handedness have often reported functional asymmetries in corticomotor excitability (CME) associated with voluntary movement. Recently, we have shown that the degree of post-exercise corticomotor depression (PED) and increase in short-interval cortical inhibition (SICI) after a repetitive finger movement task was less when the task was…more
Teo, W.P., Rodrigues, J.P., Mastaglia, F.L., Thickbroom, G.W. 2012, ‘Breakdown in central motor control can be attenuated by motor practice and neuro-modulation of the primary motor cortex’, Neuroscience, 220, pp. 11-18.
Abstract: The performance of a repetitive index finger flexion–extension task at maximal voluntary rate (MVR) begins to decline just a few seconds into the task and we have previously postulated that this breakdown has a central origin. To test this hypothesis, we have combined two objectives; to determine whether motor practice can lessen the performance deterioration…more
Rodrigues, J.P., Mastaglia, F.L., Thickbroom, G.W. 2009, ‘Rapid slowing of maximal finger movement rate: Fatigue of central motor control?’, Experimental Brain Research, 196, 4, pp. 557-563.
Abstract: Exploring the limits of the motor system can provide insights into the mechanisms underlying performance deterioration, such as force loss during fatiguing isometric muscle contraction, which has been shown to be due to both peripheral and central factors. However, the role of central factors in performance deterioration during dynamic tasks has received little attention. We studied index finger flexion/extension movement…more
Silberstein, P., Bittar, R.G., Boyle, R., Cook, R., Coyne, T., O’Sullivan, D., Pell, M., Peppard, R., Rodrigues, J.P., Silburn, P., Stell, R., Watson, P., Australian DBS Referral Guide 2009, ‘Deep brain stimulation for Parkinson’s disease: Australian referral guidelines’, Journal of Clinical Neuroscience, 16, 8, pp. 1001-1008.
Abstract: The advent of deep brain stimulation (DBS) has been an important advance in the treatment of Parkinson’s disease (PD). DBS may be employed in the management of medication-refractory tremor or treatment-related motor complications, and may benefit between 4.5% and 20% of patients at some stage of their disease course. In Australia, patients with PD are reviewed…more
Lim, S.Y., O’Sullivan, S.S., Kotschet, K., Gallagher, D.A., Lacey, C., Lawrence, A.D., Lees, A.J., O’Sullivan, D.J., Peppard, R.F., Rodrigues, J.P., Schrag, A., Silberstein, P., Tisch, S., Evans, A.H. 2009, ‘Dopamine dysregulation syndrome, impulse control disorders and punding after deep brain stimulation surgery for Parkinson’s disease’, Journal of Clinical Neuroscience, 16, 9, pp. 1148-1152.
Abstract: Data regarding the effect of deep brain stimulation (DBS) surgery on the dopamine dysregulation syndrome (DDS), impulse control disorders (ICDs) and punding in Parkinson’s disease (PD) are limited. We present a case series of 21 operated PD patients who had exhibited DDS, ICDs or punding at some stage during the disease. DDS remained unimproved or worsened…more
Netto, K.J., Burnett, A.F., Green, J.P., Rodrigues, J.P. 2008, ‘Validation of an EMG-driven, graphically based isometric musculoskeletal model of the cervical spine’, Journal of Biomechanical Engineering-Transactions of the ASME, 130, pp. -.
Abstract: EMG-driven musculoskeletal modeling is a method in which loading on the active and passive structures of the cervical spine may be investigated. A model of the cervical spine exists; however, it has yet to be criterion validated. Furthermore, neck muscle morphometry in this model was derived from elderly cadavers, threatening model validity. Therefore, the overall aim of this study was to modify and criterion validate this preexisting graphically based musculoskeletal model…more
Rodrigues, J.P., Walters, S.E., Stell, R., Mastaglia, F.L., Thickbroom, G.W. 2008, ‘Spike-timing-related plasticity is preserved in Parkinson’s disease and is enhanced by dopamine: Evidence from transcranial magnetic stimulation’, Neuroscience Letters, 448, 1, pp. 29-32.
Abstract: We sought to investigate the effects of dopamine on motor cortical plasticity in Parkinson’s disease (PD) using a novel interventional transcranial magnetic stimulation protocol that targets spike-timing-dependent plasticity (iTMS). Six patients (317, mean age 62 years) with mild-moderate PD (mean disease duration 6 years, UPDRS-off 13, UPDRS-on 3, H&Y stage 2, daily levodopa dosage 450 mg) were studied off and on levodopa on separate days. Paired TMS pulses at resting…more
Burnett, A., Green, J., Netto, K., Rodrigues, J.P. 2007, ‘Examination of EMG normalisation methods for the study of the posterior and posterolateral neck muscles in healthy controls’, Journal of Electromyography and Kinesiology, 17, pp. 635-641.
Abstract: The purpose of this study was to examine the reliability of normalisation methods used in the study of the posterior and posterolateral neck muscles in a group of healthy controls. Six asymptomatic male subjects performed a total of 12 maximum voluntary isometric…more
Rodrigues, J.P., Walters, S.E., Watson, P., Stell, R., Mastaglia, F.L. 2007, ‘Globus pallidus stimulation improves both motor and nonmotor aspects of quality of life in advanced Parkinson’s disease’, Movement Disorders, 22, 13, pp. 1866-1870.
Abstract: Our purpose was to measure the change in quality of life (QoL) following deep brain stimulation of the globus pallidus interna (GPi-DBS) in advanced Parkinson’s disease (PD), and identifies any associations with changes in motor features of the disease. Eleven patients (age range 54-69 years, 2 women) underwent GPi-DBS (4 unilateral, 7 bilateral). Outcome measures…more
Rodrigues J.P., Edwards D.J., Walters S.E., Stell R., Mastaglia F.L. 2006, ‘Pregabalin in the treatment of primary orthostatic tremor: A comparison with gabapentin’, 10th International Congress of Parkinson’s Disease and Movement Disorders, October 30-November 2, 2006, Kyoto, Japan…more
Rodrigues, J.P., Edwards, D.J., Walters, S.E., Byrnes, M.L., Thickbroom, G.W., Stell, R., Mastaglia, F.L. 2006, ‘Blinded placebo crossover study of gabapentin in primary orthostatic tremor’, Movement Disorders, 21, 7, pp. 900-905.
Abstract: Primary orthostatic tremor (OT) is a rare but disabling condition characterized by leg tremor and feelings of instability during stance. Previous studies have reported a reduction in OT symptoms with gabapentin treatment. In this study, we report on the benefits of gabapentin treatment in a double-blind placebo-controlled crossover study of 6 OT patients. First, the maximally…more
Rodrigues, J.P.T., Edwards, D.J., Walters, S.E., Byrnes, M.L., Thickbroom, G.W., Stell, R., Mastaglia, F.L. 2005, ‘Gabapentin can improve postural stability and quality of life in primary orthostatic tremor’, Movement Disorders, 20, 7, pp. 865-870.
Abstract: Primary orthostatic tremor (OT) is characterized by leg tremor and instability on standing. High frequency (13-18 Hz) tremor bursting is present in leg muscles during stance, and posturography has shown greater than normal sway. We report on an open-label add-on study of gabapentin in 6 patients with OT. Six patients were studied with surface electromyography, force platform posturography…more