Surgery-Free Brain Stimulation Uses Implanted Electrodes As New Treatment Method for Dementia

Dementia is a neurological condition that affects millions of people worldwide. It is characterized by memory loss, decline in cognitive abilities, and difficulties in performing daily activities. There is currently no cure for dementia, but experts constantly explore new treatment options to improve the quality of life of those affected by this disease.

Current Treatment Options for Dementia

Most types of dementia cannot be cured, but some medications, such as cholinesterase inhibitors and memantine, help manage the symptoms. Palliative care is also provided to improve the patient's quality of life.

Most patients with brain disorders are not amenable to pharmacological treatment, so other treatment approaches, such as brain stimulation, are preferred. Brain stimulation directly controls the aberrant neural activity that underpins the diseases.

For severe disorders such as Parkinson's disease, invasive electrical deep brain stimulations (DBS) have been used worldwide. However, there are risks associated with brain surgery that limit its potential therapeutic impact.

Non-Invasive Brain Stimulation

Experts at the Imperial College London have been developing and testing a new method of stimulating the brain. They focus on providing an alternative treatment for neurological brain diseases such as Alzheimer's and associated memory loss.

The new method, known as temporal interface (TI), delivers differing electrical field frequencies through electrodes placed on the scalp and various parts of the head. The overlapping electrical fields enable the deep region of the brain called the hippocampus to be targeted by electrical stimulation without affecting the nearby areas.

This approach was first described in 2017, where it was shown to work in principle in mice. In a new study, it has been successfully tested for the first time on 20 healthy volunteers by a group of researchers from the UK Dementia Research Institute (UK DRI) at Imperial College and the University of Surrey.

The TI stimulation was applied to healthy volunteers while memorizing pairs of faces and names. Using functional magnetic resonance imaging (fMRI), the scientists confirmed that TI selectively affected the hippocampal activity evoked by the memory task. The researchers first used post-mortem brain measurements to validate the ability of TI electric fields to be remotely focused in the hippocampus.

The initial findings suggest that when healthy adults perform a memory task while receiving TI stimulation, their memory function is improved. When the procedure was repeated for a more extended period of 30 minutes, it was revealed that TI stimulation during the task improved memory accuracy.

According to study first author Dr. Ines Violante, the ability to selectively target deep brain regions using a non-invasive approach provides a tool for investigating how the human brain operates and can open possibilities for clinical applications. She further describes that combining non-invasive imaging and brain stimulation can help unveil the processes that support human cognitive functions.

This research is published simultaneously with a second study led by experts from école Polytechnique fédérale de Lausanne (EPFL), Switzerland. In this study, the researchers used the TI technology to stimulate a deep brain area known as the striatum for improved motor memory functions in healthy volunteers.