The nervous system can change in response to new experiences or injury. This capacity for change is called neural or brain plasticity. Our continuous development of new skills and memories result from these changes.
UT Dallas researchers are at the forefront of investigations into plasticity and its role in the development of tinnitus and chronic pain, as well as stroke, traumatic brain injury, autism, schizophrenia, Alzheimer's disease and Parkinson's disease. A new method of directing plasticity by using vagus nerve stimulation of the brain is being developed. The new method could lead to highly effective therapeutic alternatives to invasive brain surgery for a wide range of disorders.
Phantom Limb Pain
Phantom limb pain occurs when a person feels pain from a body part that is amputated. Normal input to the brain is lost when the part is removed. But adjacent brain functions sometimes move into the inactive brain region and cause hyperactivity and the sensation of pain.
Targeted plasticity offers the promise of using the brain’s natural ability to reorganize to treat phantom limb pain and other neurological disorders. When the vagus nerve in the neck is stimulated, chemicals in the brain are released, strengthening connections.
By pairing vagus nerve stimulation with stimuli, researchers may be able to prompt specific forms of plasticity, or reorganization. A treatment for phantom limb pain could be developed by pairing vagus nerve stimulation with touch, reversing the effects of harmful plasticity and overcorrection after trauma.
Neural plasticity, the natural ability of the brain to reorganize, is required for learning and memory. But maladaptive plasticity occurs when the brain overcorrects when responding to the loss of normal input or trauma.
Chronic pain can result from an injury that causes greater activity in the brain’s somatosensory cortex. Scientists believe the hyperactive region can spread to surrounding brain regions over time, causing people to feel chronic pain, even after the injury has healed.
Scientists now are working on pairing vagus nerve stimulation with touch to release chemicals in the brain that strengthen active connections. Combining touch with the nerve stimulation in the neck could activate regions above and below the hyperactive region. By pairing nerve stimulation with stimuli, clinicians could drive specific forms of plasticity and reverse negative overreactions.
Chronic tinnitus is a persistent ringing in the ears that affects about 23 million Americans and one-third of active duty military veterans. Scientists from UT Dallas recently demonstrated that chronic tinnitus is not in the ears but results from pathological activity in the hearing part of the brain.
A new approach is being studied to possibly cure tinnitus by rewiring the brain to eliminate the neural activity that causes it. The new therapy is highly successful in curing rats with tinnitus. Human clinical trials, involving a vagus nerve stimulation device developed by MicroTransponder, are underway.
VIDEO: Tinnitus Therapy
VIDEO: Ch. 8 News, Tinnitus Therapy
PODCAST: National Institute for Deafness and Other Communication Disorders
Stroke is one of the most common causes of disability. But neural plasticity, the natural ability of the brain to reorganize, may offer hope to millions of patients.
Stimulation of the neck’s vagus nerve releases chemicals in the brain that strengthen active connections that may have been damaged by the loss of neural input after a stroke or trauma. By pairing vagus nerve stimulation with stimuli such as touch, researchers may be able to drive specific forms of beneficial plasticity.
This targeted plasticity could be used to restore functions lost because of stroke or brain injury. As the patient’s condition improves, a new brain region could gain the ability to generate the impaired movement. Vagus nerve stimulation delivered during physical therapy has the potential to drive plasticity to accelerate recovery.
Cochlear implants are surgically implanted devices that send sound signals to the brain. They are used by people who receive little benefit from hearing aids. Engineers at UT Dallas are programming these devices to operate more effectively in a range of listening conditions.
The team has developed an interface that enables wearers to use smartphones to adjust the device to varying levels of background noise. Users could gain more flexibility and independence in everyday life.
UT Dallas’ research and clinical centers are longtime leaders in the advancement of cochlear implants. The newly created Communications Technology Center will foster collaboration among neuroscientists, engineering researchers and faculty members from the Callier Center for Communication Disorders. Among their projects are efforts aimed at figuring out how to make cochlear implants work better, with fewer potential side effects.