Focus Area
Nervous System Health
Our Focus
Nervous System Health
The nervous system, including the brain, spinal cord, and peripheral nerves, facilitates all body parts to communicate and react to internal and external changes.
Nervous System Health
The nervous system’s health improves mental and physical well-being and creates positive social and economic impacts. However, neurological conditions are the leading cause of disability-adjusted life years and the second leading cause of death globally, according to WHO1.
Neurological Disorders
Neurological disorders include a wide range of conditions. Hundreds of millions of people worldwide are affected by these diseases. Major neurological disorder types include
Degenerative Diseases
Neurodegenerative disorders are a group of conditions that result from progressive damage to cells and neural connections that are essential for mobility, coordination, strength, sensation, and cognition.
Parkinson’s disease (PD) is a progressive brain disorder with a particular group of brain cells gradually breaking down that causes unintended or uncontrollable movements. Symptoms include shaking, stiffness, and difficulty with balance and coordination. Propelled by an increasingly aging population, PD is the fastest growing neurological disorder, with more than 8.5 million people affected worldwide in 20192. Treatment options such as medications and deep brain stimulations can help control the symptoms.
Alzheimer’s disease (AD) is a progressive brain disorder that slowly destroys memory and thinking skills. The most common cause of dementia is loss of cognitive functioning and behavioral abilities. Nearly 50 million people suffer from AD or AD-related dementia worldwide in 20193. There is no clear understanding of the disease mechanism, so treatment options are limited. Several medications are available to help maintain mental function and slow or delay the symptoms.
Other neurodegenerative diseases include Amyotrophic lateral sclerosis (ALS), Huntington’s disease, multiple system atrophy, ataxia, etc.
Epilepsy
Epilepsy is a neurological disorder in which brain cell activities become abnormal, causing seizures or periods of unusual behavior and sometimes loss of awareness. The disease can happen to people of all ages, and around 50 million people worldwide are affected4.
Epilepsy can be caused by conditions such as stroke, brain tumor, head injury, and infection, but the cause is often unknown. The primary treatments for epilepsy include medications, neurostimulations, and surgery.
Neuropathic Pain
Neuropathic pain is caused by a lesion or disease of the nervous system, which leads to the altered and disordered transmission of sensory signals into the spinal cord and brain. The traditional approach to managing neuropathic pain is medications.
However, the limited efficacy of drugs and the recent push for opioid-free therapies have inspired the development of novel device approaches to managing chronic pain, such as spinal cord stimulation, transcranial magnetic stimulation, and transcutaneous electrical nerve stimulation.
Migraine
A migraine is a recurring headache that can cause moderate to severe throbbing pain or pulsing sensation. The disease is associated with a substantial personal and societal burden and can also affect mental health and well-being. Migraine is the second among the world’s causes of disability and first among young women5.
The estimated global prevalence of migraine is about 14%6. Drugs are mainly used to relieve symptoms and prevent additional attacks. Device options (e.g., neurostimulations) are also available for patients concerned about drug side effects.
Other neurological disorders include spinal cord or brain injuries, genetic diseases (e.g., Huntington’s disease, muscular dystrophy), developmental conditions (e.g., ADHD, autism, cerebral palsy), vascular conditions (e.g., stroke, aneurysm), cancer and infections.
Treatments and Therapies
Neurostimulation is a major therapy tool for treating neurological disorders, which uses electrical or magnetic stimulations to modulate neural functions. The global neurostimulation devices market size was valued at US$6 billion in 2021 and will be valued at US$14 billion by 20307. Neurostimulation therapies include invasive and noninvasive approaches.
Invasive Neurostimulation Therapies
DBS is a neurosurgical procedure that uses implanted electrodes to send electrical stimulations to specific targets in the brain and regulate the activities of certain brain cells. DBS has been used to treat a number of conditions, such as Parkinson’s disease, essential tremor, epilepsy, dystonia, and obsessive-compulsive disorder. DBS is also being studied as a potential treatment for depression, pain/headache, Alzheimer’s disease, and addiction.
SCS therapy surgically places a stimulator under the skin and sends a mild electric current to the spinal cord to modify and mask the pain signal from reaching the brain. SCS can treat or manage chronic pains due to various conditions, including failed back surgery, neuropathic pain, and complex regional pain syndrome.
VNS is a type of neuromodulation that uses an implantable device to send electrical impulses to stimulate the vagus nerve in the neck. The electrical impulses travel to the brain, where it is dispersed to different areas to change the way brain cells work. VNS has been used for epilepsy therapy, depression treatment, and stroke rehabilitation.
RNS is an epilepsy treatment that helps prevent seizures before they begin. RNS is a “closed loop” system that continuously monitors the brain’s electrical activity and sends a brief electrical stimulation pulse to control abnormal brain activity when a seizure is detected.
TMS is a noninvasive form of brain stimulation involving magnetic fields to influence brain activity. An electromagnetic coil is placed on the scalp, and a magnetic field is generated to activate or inhibit cells in a specific part of the brain. TMS has been used to treat depression, obsessive-compulsive disorder, migraine, and smoking addiction. Research is ongoing to study TMS treatment for Alzheimer’s, chronic pain, Parkinson’s, etc.
TENS is a non-invasive, portable, and inexpensive peripheral technique stimulating nerves for therapeutic purposes. During TENS, pulsed electrical currents are delivered through attached electrodes across the skin’s surface to activate underlying nerves. TENS is a commonly used treatment approach to alleviate acute and chronic pain.
In addition, neurostimulations also involve cochlear implants, retinal implants, sacral nerve stimulation, gastric electric stimulation, etc. Besides neurostimulations, other treatments for neurological disorders include medications, vascular interventions, and cognitive behavior therapy.
Unmet Needs
The global burden of neurological disorders is expected to increase dramatically within the following decades, resulting from extended life expectancy and the aging of populations. So far, most neurological disorders cannot be cured, and current treatments only focus on maintaining the nervous system functions or delaying the symptoms.
The biggest challenge for reducing the global health burden of neurological conditions is a paradigm shift from symptomatic to disease-modifying treatments. Additionally, many disease mechanisms are still not fully understood, making it challenging to develop effective therapies. For example, the biological mechanisms underlying Alzheimer’s disease are poorly understood; as a result, there are very few effective treatments and no cure for the disease.
Moreover, the exact therapeutic mechanisms of many neurostimulation treatments are still unknown. Therefore, a better understanding of disease and therapy mechanisms becomes necessary to develop novel disease-modifying treatments.
Neurotech Advancements
There are enormous opportunities to improve technology and explore new approaches. Neuroscience discovery into disease mechanisms, combined with advancements in computational capabilities, miniaturization, and material sciences, enable the development of new device therapies.
For example, most current neurostimulation systems have an “open-loop” design with static stimulation settings; however, the recent development of “closed-loop” neurostimulation systems makes it possible to dynamically adjust and customize stimulation based on a patient’s real-time status. This optimization approach is being explored for the improvement of deep brain stimulation and spinal cord stimulation.
References
- WHO and the World Federation of Neurology. ATLAS Country Resources for Neurological Disorders. Sep 2017.
- WHO. Parkinson Disease a Public Health Approach: Technical Brief. Jun 2022.
- Mayo Clinic. Alzheimer’s Disease Symptoms and Causes. Feb 2022.
- WHO. Epilepsy Fact Sheets. Feb 2022.
- Steiner TJ et al. Lifting the Burden: the Global Campaign Against Headache, GBD2019. J Headache Pain. 2020 Dec 2;21(1):137.
- tovner LJ et al. The Global Prevalence of Headache. J Headache Pain. 2022 Apr 12;23(1):34.
- Straits Research. Neurostimulation Devices Market. Aug 2020.
