A5005404659- Neurological disorders and treatments
- Neuroscience and Neural Engineering
- Neural dynamics and brain function
- Parkinson's Disease Mechanisms and Treatments
- EEG and Brain-Computer Interfaces
- Functional Brain Connectivity Studies
- Genetic Neurodegenerative Diseases
- Transcranial Magnetic Stimulation Studies
- Neuroscience and Neuropharmacology Research
- Photoreceptor and optogenetics research
- Molecular Communication and Nanonetworks
- Advanced MRI Techniques and Applications
- Wireless Body Area Networks
- Sleep and Wakefulness Research
- Markov Chains and Monte Carlo Methods
- Autism Spectrum Disorder Research
- Muscle activation and electromyography studies
- Visual perception and processing mechanisms
- Neural and Behavioral Psychology Studies
- Technology and Human Factors in Education and Health
- Face Recognition and Perception
- Supramolecular Chemistry and Complexes
- Time Series Analysis and Forecasting
- Protein Structure and Dynamics
- Botulinum Toxin and Related Neurological Disorders
University of Oxford
2016-2025
MRC Brain Network Dynamics Unit
2016-2025
Medical Research Council
2016-2025
University College London
2015-2025
Imperial College London
2023-2025
Wellcome Centre for Human Neuroimaging
2015-2023
John Radcliffe Hospital
2012-2022
National Hospital for Neurology and Neurosurgery
2015-2022
Philips (Netherlands)
2009-2011
<h3>Introduction & objectives</h3> Adaptive deep brain stimulation (aDBS) uses feedback from signals to guide stimulation. A recent acute trial of unilateral aDBS showed that can lead substantial improvements in contralateral hemibody Unified Parkinson’s Disease Rating Scale (UPDRS) motor scores and may be superior conventional continuous DBS disease (PD). We test whether potential benefits are retained with bilateral the face concurrent medication. <h3>Methods</h3> applied 4 patients PD...
This tutorial provides a worked example of using Dynamic Causal Modelling (DCM) and Parametric Empirical Bayes (PEB) to characterise inter-subject variability in neural circuitry (effective connectivity). involves specifying hierarchical model with two or more levels. At the first level, state space models (DCMs) are used infer effective connectivity that best explains subject's neuroimaging timeseries (e.g. fMRI, MEG, EEG). Subject-specific parameters then taken group where they modelled...
This paper revisits the dynamic causal modelling of fMRI timeseries by replacing usual (Taylor) approximation to neuronal dynamics with a neural mass model canonical microcircuit. provides generative or laminar specific responses that can generate haemodynamic and electrophysiological measurements. In principle, this allows fusion (event related induced) responses. Furthermore, it enables Bayesian comparison competing hypotheses about physiologically plausible synaptic effects; for example,...
See Moll and Engel (doi:10.1093/aww308) for a scientific commentary on this article. Brain regions dynamically engage disengage with one another to execute everyday actions from movement decision making. Pathologies such as Parkinson’s disease tremor emerge when brain controlling cannot readily decouple, compromising motor function. Here, we propose novel stimulation strategy that selectively regulates neural synchrony through phase-specific stimulation. We demonstrate the first time...
Significance Prevalence and temporal dynamics of transient oscillations in the beta frequency band (15 to 35 Hz), referred as β bursts, are correlated with motor performance. Disturbance these activities is a candidate mechanism for impairment Parkinson’s disease (PD), where excessively long bursts correlate symptom severity reduced by pharmacological surgical treatments. Here we describe changes action potential firing that take place across multiple nodes cortical basal ganglia circuit...
See Vidailhet et al. (doi:10.1093/brain/awx140) for a scientific commentary on this article. Misdiagnosis among tremor syndromes is common, and can impact both clinical care research. To date no validated neurophysiological technique available that has proven to have good classification performance, the diagnostic gold standard evaluation made by movement disorders expert. We present robust new measure, stability index, which discriminate Parkinson’s disease essential with high accuracy. The...
Synchronized oscillations within and between brain areas facilitate normal processing, but are often amplified in disease. A prominent example is the abnormally sustained beta-frequency (∼20 Hz) recorded from cortex subthalamic nucleus of Parkinson's disease patients. Computational modeling suggests that amplitude such could be modulated by applying stimulation at a specific phase. Such strategy would allow selective targeting oscillation, with relatively little effect on other activity...
There is growing evidence for exaggerated oscillatory neuronal synchronisation in patients with Parkinson's disease. In particular, oscillations at around 20 Hz, the so-called beta frequency band, relate to cardinal symptoms of bradykinesia and rigidity. Deep brain stimulation subthalamic nucleus can significantly improve these motor impairments. Recent has demonstrated reduction concurrent alleviation PD symptoms, raising possibility that suppression aberrant activity may mediate effects...
Tremor is a cardinal feature of Parkinson's disease and essential tremor, the two most common movement disorders. Yet, mechanisms underlying tremor generation remain largely unknown. We hypothesized that driving deep brain stimulation electrodes at frequency closely matching patient's own should interact with neural activity responsible for effect on reveal role different targets in generation. Moreover, responses to might pathophysiological differences between parkinsonian circuits....
Parkinson's disease is a common and debilitating condition, caused by aberrant activity in complex basal ganglia-thalamocortical circuit. Therapeutic advances rely on characterising interactions this However, recording electrophysiological responses over the entire circuit impractical. Dynamic causal modelling offers large-scale models of predictive value based limited or partial sampling networks. Using dynamic modelling, we determined network changes underlying pathological excess beta...
High frequency deep brain stimulation of the thalamus can help ameliorate severe essential tremor. Here we explore how efficacy, efficiency and selectivity thalamic might be improved in this condition. We started from hypothesis that effects electrical on tremor may phase dependent, that, particular, there are phases at which stimuli preferentially lead to a reduction amplitude The latter could exploited improve stimulation, particularly if suppression reinforced by cumulative effects....
Optimal phase alignment between oscillatory neural circuits is hypothesized to optimize information flow and enhance system performance. This theory known as communication-through-coherence. The basal ganglia motor circuit exhibits exaggerated coherent activity patterns in Parkinson's disease. Such are linked compromised performance evinced by bradykinesia, rigidity tremor, suggesting that network function might actually deteriorate once a certain level of net synchrony exceeded the circuit....
Parkinson's disease (PD) and essential tremor (ET) are the two most common movement disorders. Both have been associated with similar patterns of network activation leading to suggestion that they may result from dysfunction, specifically involving cerebellum. Here, we demonstrate parkinsonian tremors ETs distinct interactions between neural oscillators. These reflected in tremors' derived frequency tolerance, a novel measure readily attainable bedside accelerometry. Frequency tolerance...
Deep brain stimulation (DBS) is known to be an effective treatment for a variety of neurological disorders, including Parkinson's disease and essential tremor (ET). At present, it involves administering train pulses with constant frequency via electrodes implanted into the brain. New 'closed-loop' approaches involve delivering according ongoing symptoms or activity have potential provide improvements in terms efficiency, efficacy reduction side effects. The success closed-loop DBS depends on...
We present a technical development in the dynamic causal modelling of electrophysiological responses that combines qualitatively different neural mass models within single network. This affords option to couple various cortical and subcortical nodes differ their form dynamics. Moreover, it enables users implement new straightforward standardized way. generic framework hence supports flexibility facilitates exploration increasingly plausible models. illustrate this by coupling basal...
Abstract Essential tremor manifests predominantly as a of the upper limbs. One therapy option is high-frequency deep brain stimulation, which continuously delivers electrical stimulation to ventral intermediate nucleus thalamus at about 130 Hz. Constant can lead side effects, it therefore desirable find ways stimulate less while maintaining clinical efficacy. strategy, phase-locked consists stimulating according phase tremor. To advance methods optimise providing insights into circuits, we...
Abstract Background Tremor phase-locked deep brain stimulation (DBS) has been shown to modulate symptom severity in patients with postural tremor, including essential (ET) and dystonic tremor (DT). This, provides a potential alternative therapy that targets the underlying pathological oscillations less energy delivered than existing systems. Previous DBS studies focused on evaluating effect of unilateral tremor-dominant hand. Considering usually presents bilaterally, it remains unknown how...