Tan Group

motor

Rendered whole brain magnetic resonance image showing which cortical areas have their activities coupled with those in the motor region of the subthalamic nucleus in Parkinson’s disease. Coupling is determined by simultaneous recordings of magnetoencephalographic activity and deep brain recordings in patients with electrodes implanted for deep brain stimulation treatment. Representative deep brain waves are also shown. The effects of drugs and of high frequency stimulation on coupling and deep brain activity can thereby be determined, and provide clues as to how treatments can be improved.

Our goal is to define how activity in large populations of neurons is coordinated in healthy movement and how such coordination may go awry in diseases, translating this information in to improved treatment for Parkinson’s Disease, Essential Tremor and other disorders of movement.

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Adaptive stimulation in patients with Parkinson's Disease using local field potential

beta
plots beta frequency activity of left and right STN under ON and OFF levodopa conditions- showing OFF results in strong local synchronisation due to long duration beta bursts, and ON having shorter bursts and limited synchronisation.
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on the left: a diagram of a human subject with grips used for feedback in a task; also shows stimulation and recording electrodes in the subject's brain, while viewing a visual task. On the right there are two plots of reaction time and movement time, ON vs OFF stimulation, speed vs accuracy

Stimulation is used to probe the causal role of neural oscillations at specific times in motor control and decision-making.

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Treating Parkinson's Disease Using Machine Learning

(Click below to play video. Fullscreen and quality options at bottom right)

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figure showing diagram of a hand on a joystick, and a plot of movement velocity vs. beta band activity in the LFP, and an indication that a beta burst before the go signal leads to reduced velocity in the movement.

Modulation of Beta Bursts in the Subthalamic Nucleus Predicts Motor Performance.

Group Science

The Group takes a multidisciplinary approach, combining experimental manipulations in healthy subjects and patients with sophisticated signals analysis and modelling. Our experimental manipulations include non-invasive brain stimulation, and often involve patients who have had deep brain stimulation electrodes implanted as treatment for problems with movement. Over the years we have made major advances in understanding how abnormal interactions between brain cells cause slowness of movement, tremor and stiffness in people with Parkinson’s disease. At the same time we have leveraged these insights to pioneer closed-loop approaches to therapeutic brain stimulation. Currently we are refining these closed-loop strategies still further, and extending them to the treatment of gait dysfunction and essential tremor. We are also capitalising on our understanding of circuit dynamics in the basal ganglia to help predict, with high spatial resolution, optimal sites for therapeutic stimulation, and are exploiting local dynamics in basal ganglia nuclei as a basis for Brain-Computer Interfaces that control the environment for paralysed patients.

Key Research Areas
  • Oscillations within subcortico-cortical motor loops in health and disease
  • Decoding circuit dynamics to understand and manipulate function
  • Closed-loop approaches to the treatment of movement disorders like Parkinson’s and Essential Tremor
  • Development of novel BCI systems based on subcortical signals for neuroprosthetic control and neural feedback training
  • Non-invasive brain stimulation
Longer-term Perspectives

We are at the beginning of a therapeutic revolution whereby we can interact with neural dynamics from moment-to-moment as necessary to reverse or ameliorate dysfunctional brain activity. To this end, we must record and interpret brain signals in real-time with sufficient temporal and spatial resolution to give nuanced control. Although electrical brain stimulation is already affording major therapeutic benefits, there is vast scope for improving and extending this to provide adaptive and tailored interventions, and for harnessing recent advances in non-invasive stimulation techniques to deliver multisite manipulation of brain circuits.

Equality and Diversity

We are committed to fostering an inclusive work environment that celebrates diversity and promotes equal opportunity within our group and the wider MRC BNDU.

Group Leader
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photo of Huiling Tan
Group News
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A photo of Beatriz Silveira de Arruda, Ashwini Oswal, and Simon Farmer.

After the viva voce: A happy D.Phil. candidate (centre) with satisfied examiners (left and right).

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Photo of Camille Lasbareilles (seated) and Ioana Grigoras (standing) with members of the Unit’s Patient and Public Advisory Group.

Unit early-career researchers Camille Lasbareilles and Ioana Grigoras demonstrate transcranial magnetic stimulation to members of the Unit’s Patient and Public Advisory Group.

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A woman, a man and another woman stand facing the camera, the man in the middle holds a metal award- a sculpture of two film strips in a double helix.

Rob Key (middle; representing Oxford Sparks) and Demi Brizee (right; representing the MRC Brain Network Dynamics Unit) receive the award for Best Film Produced by Universities and Research Institutes.

Photo credit: Manuel Castells Clemente / #LabMeCrazy! International Film Festival

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A group photo of attendees at the Unit’s Science Day in winter 2023.

Attendees at the MRC BNDU’s Science Day in Winter 2023.

Selected Publications
Unit Publication
He S
Baig F
Merla A
Torrecillos F
Perera A
Wiest C
Debarros J
Benjaber M
Hart MG
Ricciardi L
Morgante F
Hasegawa H
Samuel M
Edwards MJ
Denison T
Pogosyan A
Ashkan K
Pereira EA
Tan H

2023. Brain, 146(12):5015-5030.

Unit Publication
Torrecillos F
He S
Kühn AA
Tan H

2023. NPJ Parkinsons Dis, 9(1):93.

Unit Publication
Wiest C
Morgante F
Torrecillos F
Pogosyan A
He S
Baig F
Bertaina I
Hart MG
Edwards MJ
Pereira EA
Tan H

2023. Mov Disord, 38(3):423-434.

Unit Publication
Herz DM
Bange M
Gonzalez-Escamilla G
Auer M
Ashkan K
Fischer P
Tan H
Bogacz R
Muthuraman M
Groppa S
Brown P

2022. Nat Commun, 13(1):7530.

Unit Publication
Debarros J
Brown P
Tan H
Denison T
2020. WO/2020/165591
Datasets and resources

Like other Groups at the MRC BNDU, we are committed to best practice in open research.  We have created and curated a range of primary data, metadata and related resources that can be readily downloaded by external users from the MRC BNDU's Data Sharing Platform. We highlight below just a few examples of the datasets and other resources we have shared for the benefit of our stakeholders.

Wiest C
Torrecillos F
Pogosyan A
Baig F
Pereira E
Morgante F
Ashkan K
Tan H
10.5287/bodleian:mzJ7YwXvo
He S
Everest-Phillips C
Brown P
Tan H
10.5287/bodleian:9gM209oXo
Fischer P
Brown P
Tan H
10.5287/bodleian:M81wpxae8
Torrecillos F
Brown P
Tan H
10.5287/bodleian:rbR9ARpjB