Imperial College London

Researcher wins prize for method that reaches into the brain, without surgery

by ,

Dr Nir Grossman

Dr Nir Grossman

A technique for stimulating the brain with electrical fields could hold the key to treating a range of brain disorders.

Dr Nir Grossman, from the Department of Medicine, has been awarded the 2018 Science & PINS Prize for Neuromodulation for describing how the method, which applies small overlapping electric fields to the scalp, could one day help patients with neurological conditions for whom first line treatments do not work.

A growing body of clinical evidence shows that electrical currents can be used to target specific regions of the brain, changing their activity and helping to alleviate symptoms of some chronic conditions, such as the stiffness and tremors experienced in Parkinson’s disease.

However, this can carry risks due to its invasive nature – with electrodes having to be surgically implanted deep into the brain.

The Temporal Interference equipment
Researchers at Imperial are developing a new method of brain stimulation called temporal interference

Brain stimulation

Currently, there are two main methods of brain stimulation, either internal, by implanting electrodes into the brain (called deep brain stimulation or DBS) or external, by applying a strong electrical current or electromagnetic field to the scalp (such as Transcranial Electrical Stimulation (TES) or Transcranial Magnetic Stimulation (TMS).

These external methods are unable to target regions deep in the brain without stimulating the layers above, however, including the cortical layers which regulate higher functions such as thinking and processing language.

  • Dr Nir Grossman explaining the non-invasive method for stimulating the brain

    Dr Nir Grossman (pictured) is investigating temporal interference

  • Dr Nir Grossman lifts the lid of the equipment

    Dr Grossman has been awarded the 2018 Science & PINS Prize for Neuromodulation for describing how the method could one day help patients with neurological conditions for whom first line treatments do not work

  • Inside the equipment. A view of the circuitry inside the brain stimulator

    Inside the equipment. A view of the circuitry inside the brain stimulator

  • The system's interface on a laptop screen

    The system's interface on a laptop screen

Dr Grossman, a Fellow of the Dementia Research Institute, is investigating a non-invasive technique called temporal interference (or TI) – first described in the journal Cell last year – which he hopes could offer an alternative for huge number of patients in need, without the need for surgery and the associated complications, or interfering with higher functions.

“Deep brain stimulation has proven highly effective in treating Parkinson’s disease and obsessive-compulsive disorder, and it shows great potential for other conditions as well, such as depression,” explains Dr Grossman. “However, the process requires surgery to insert the electrodes to where they are needed, which can carry complications”. 

Temporal Interference: a different approach

Dr Grossman’s method takes a different approach. Rather than directly targeting a brain region with an implanted electrode, TI uses electric fields of different frequencies to subtly ‘nudge’ brain activity.

The process involves using electrodes attached to the scalp, with small amounts of electrical current applied, generating two high frequency electric fields of slightly different frequencies.

By themselves, the electrical fields are too rapid to change the activity of the brain cells, he explains. But at the point where the two fields cross, the amplitude (or wave height) of their combined currents changes at a low frequency, and this can stimulate brain cells and subtly alter their activity.

  • Dr Grossman and the equipment

    Dr Grossman explains: “This type of non-invasive stimulation could offer huge benefit to the large number of patients in need of neural therapy.”

  • Dr Grossman points at a screen showing altered wavelengths

    Multiple high frequency electric fields can stimulate the brain

  • Applying electrodes to the scalp

    The process involves using electrodes attached to the scalp, to apply small amounts of electrical current

  • The interface

    The interface: Electrical currents can be used to target specific regions of the brain, changing their activity

  • Testing TI in healthy volunteer

    The next steps will see trials in more healthy controls and patients with brain disorders

  • The resting electrical output

    By themselves the electrical fields are too rapid to change the activity of brain cells

  • Waveforms change from flat to modulated pitch

    Where the two fields cross the amplitude (or wave height) of their combined currents changes


What makes the technique so enticing is the ability to alter the point at which the fields cross, so changing the focus of the stimulation and potentially stimulating regions deep in the brain without affecting the surrounding brain areas.Early trials in mice have shown that TI can target and stimulate cells in the hippocampus, a region deep in the brain which plays important roles in memory and cognition, without affecting the cortex.

The next steps will be to test TI in healthy human volunteers, before seeing if it can work for patients with neurological conditions, and if it can match the effectiveness of DBS, but without the need for surgery. 

“As TI uses well-known electrical fields and doesn’t require us to change the brain – chemically or genetically – like other methods, we hope this will speed up its clinical deployment,” explains Dr Grossman.

“This type of non-invasive stimulation could offer huge benefit to the large number of patients in need of neural therapy.”

-

The full essay ‘Modulation without surgical intervention’ is published in the journal Science.

Article images: Thomas Angus / Imperial College London 

Reporters

Thomas Angus [Photographer]

Thomas Angus [Photographer]
Communications and Public Affairs

Click to expand or contract

Contact details

Tel: +44 (0)7714 051 684
Email: t.angus@imperial.ac.uk

Show all stories by this author

Ryan O'Hare

Ryan O'Hare
Communications and Public Affairs

Click to expand or contract

Contact details

Tel: +44 (0)20 7594 2410
Email: r.ohare@imperial.ac.uk

Show all stories by this author

Tags:

Strategy-share-the-wonder, Brain, Strategy-multidisciplinary-research, Dementia
See more tags

Comments

Comments are loading...

Leave a comment

Your comment may be published, displaying your name as you provide it, unless you request otherwise. Your contact details will never be published.