New Device Stimulates Recovery From TBI Through The Tongue

The tongue is connected to the brain by thousands of cranial nerve fibers. There are motor fibers running from the brain to the tonue that activate the muscles of the tongue and there are sensory fibers (in the facial and glossopharyngeal nerves) that bring sensations from the tongue to the brain. Very recently researchers at the U.S. Army Medical Research and Materiel Command have collaborated with researchers at the University of Wisconsin-Madison and NeuroHabilitation Corporation to use the sensory nerves of the tongue as a pathway to stimulate the brain and regenerate damaged brain tissue following TBI, stroke or MS.

They have created an experimental device they call the PoNS (a battery operated appliance covered with electrodes) that gets placed upon the tongue and sends specially-patterned nerve impulses to a patient’s brain. The electro-stimulation of the tongue is done in tandem with a custom set of physical, occupational, and cognitive exercises, based on the patient’s deficits.

The idea is to improve the brain’s organizational ability and allow the patient to regain neural control. The PoNS prototype and associated therapy were developed by University of Wisconsin-Madison scientists Yuri Danilov, Ph.D., Mitchell Tyler, M.S., P.E., and Kurt Kaczmarek, Ph.D. Their research is driven by the principle that brain function is not hardwired or fixed, but can be reorganized in response to new experiences, sensory input and functional demands. If the ongoing research shows the PoNS device to be safe and effective, the collaborators will apply for FDA approval.

Modern Definition of Traumatic Brain Injury

According to the National Institutes of Healh a traumatic brain injury (TBI) is “an injury from a blow, jolt, or penetrating object that disrupts normal functioning of the brain. Causes of TBI include falls, car accidents, sports-related impacts, and penetrating injuries. A TBI can be mild, some​times called a concussion; serious, causing long-term problems; or any level in between.”

How the Brain Adapts to TBI

For the first time, scientists at Carnegie Mellon University’s Center for Cognitive Brain Imaging have used a combination of neural imaging methods to discover exactly how the human brain adapts to injury. The research, published in January 2013 issue of Cerebral Cortex, shows that when one brain area loses functionality, a “back-up” team of secondary brain areas immediately activates, replacing not only the unavailable area but also its confederates. The researchers used 16 healthy adult volunteers. They had each one engage in comprehending a sentence inside a machine using fMRI to scan their brain activity. The scanning continued before, during, and after the researchers used a TMS machine to send a pulse of magnetic energy into the precise area of the volunteers’ brains (the Wernicke’s area in the left temporal lobe) which is directly involved in language comprehension. What they found was that although Wernicke’s area was temporarily immobilized, three other back-up areas of the brain immediately activated and coordinated to assist the volunteer in comprehending the sentence. These areas were the frontal lobes (the area of executive function), the contra-lateral area on the right side of the brain that mirrors the Wernicke’s area but has different functions, and the brain areas next to Wernicke’s area.

This experiment served as a very rapid snapshot of what may take place over a much longer time in the brain of a person who suffered a TBI or stroke. In the case of a TBI or stroke victim there is usually a period of global brain impairment with gradual resumption of normal functioning except those functions related to the specific area(s) where the greatest damage occurred. The study shows that brain activities occur not in single areas but in groups and that back-up groups of unharmed cells can be recruited to take over for damaged cells.

Doctor examining a brain CT scan

MRI is better at detecting lesions from Mild TBI than CT Scans

A clinical trial at 3 large, urban hospitals with Level I trauma services showed that MRIs are better at predicting long-term outcomes for people with mild traumatic brain injuries than CT scans. The hospitals which participated in this study were the University of Pittsburg Medical Center, UCSF and the San Francisco General Hospital and Trauma Center. The lead author of the study was UCSF neuroradiologist Esther Yuh, MD, PhD .

The study was published in the December 2012 issue of the Annals of Neurology. The central finding on 135 patients followed for mild TBI was that 99 of the patients showed no brain abnormality on the CT scan adminsitered in the Emergency Department but just one week later 27 of these 99 patients showed focal lesions on MRI demonstrating pockets of microscopic bleeding in the brain. About 15 percent of people who have mild traumatic brain injuries do suffer persistent, long-term neurological consequences. MRI done one week post-trauma should help doctors better predict which patients will fall into the 15% group.

White Matter Damage Persists After Pediatric MTBI

Is the brain of a child more vulnerable to mild traumatic brain injury (MTBI) than an adult? In the December 12, 2012 issue of the Journal of Neuroscience researchers published a study showing that damage to the white matter of the brain first detected 2 weeks after MTBI in children (ages 10-17) was still visible 3 months post-injury on DTI brain scanning. The damage was present even though the children had stopped reporting symptoms. This study contradicts the assumption that the brains of children heal rapidly and completely from MTBI. The white matter of the brain consists of long nerve fibers (axons) that carry messages from one part of the brain to another. Thus the persistence of visible white matter damage 3 months after MTBI is a concern that warrants further investigation.

APOE-e4 allele predicts worse outcome after TBI

The APOE-e4 allele is a gene mutation associated with incresed risk of Alzheimer’s disease. Does possession of this gene mutation contribute to worse outcome following TBI? In the Journal of Neurotrauma 25:279–290 (April 2008) Zhou and colleges carried out a comprehensive survey and meta-analysis of cohort studies of sufficient rigor to determine whether the presence of the APOE4 allele contributes to poor outcome following traumatic brain injury (TBI). They 100 identified studies between 1993 and 2007 they selected 14 cohort studies for analysis based on comprehensive quality assessment. These studies included a total of 2527 participants, 736 with and 1791 without the APOE4 allele. The studies showed that possession of the APOE-e4 allele was not associated with initial injury severity of TBI.

However, the APOE4 allele was significantly associated with a poor outcome of TBI at 6 months after injury. While knowing that a victim of TBI has the gene mutation does not create any new or improved treatment options, it can explain in litigation why a mild or moderate TBI has more severe consequences than ordinarily anticipated.

Preventing Epilepsy from Contusive Brain Injury

The most common cause of acquired epilepsy in teens and young adults is traumatic brain injury resulting from head contact. This year Associate Prof. of Neurosurgery Raimondo D’Ambrosia at the University of Washington performed an experment to test the cooling hypothesis. He gave a contusive brain injury to a group of rats. Half the rats received mock cooling for 5 weeks while the other half received head cooling within (but not exceeding) 2 degrees Celsius for 5 weeks. The sham-cooled rats showed a high degree of post-traumatic epilepsy, while the rats who had their heads cooled showed almost none. Dr. D’Ambrosia will seek permission to try the cooling treatment on humans to see if he gets the same highly protective effect.

TBI Patients Should Not Drink Grapefruit Juice While Taking Zoloft

Depression is a common consequence of traumatic brain injury. Zoloft is one of the most commonly prescribed anti-depressants for mild depression. If you have suffered depression or an aggravation of pre-existing depression from a TBI and your doctor has prescribed Zoloft, make sure you do not drink any grapefruit juice. Compounds within the juice not only interfere with this drug but can cause serious adverse effects when the juice in consumed by a person using the drug. The same problem has been found with the anti-anxiety drug BuSpar. In general the adverse effects involve difficulty breathing on a spectrum from mild to severe.

TBI Influences Dementia Symptoms Later in Life

Some studies have indicated that TBI sustained early in life raises the risk of dementia during one’s elderly years. Researchers at the Icahn School of Medicine at Mt. Sinai wanted to know if patients with dementia who had a TBI earlier in life had a distinct clinical profile from dementia patients with no prior history of TBI. After carrying out a study they found certain significant differences.

The results of the study indicate that compared to older adults with dementia with no history of TBI, those with a history of TBI had higher fluency and verbal memory scores and later onset of decline. However, their general health was worse, they were more likely to have received medical attention for depression, and were more likely to have a gait disorder, falls, and motor slowness. Lead study author Kristen Dams-O’Connor, Ph.D. said that in light of these differences it is important for a doctor diagnosing dementia to find out if the patient had a TBI earlier in life.

Voice Changes Help Diagnose TBI

The Notre Dame team Athletic Dept. has developed a tablet-based testing system that captures the voice of an individual and analyzes the speech for signs of a potential concussion anytime, anywhere, in real time. The benefit of this technology is that nearly 90 percent of concussions go unrecognized when they occur. The way it works is that an athelete speaks into a tablet equipped with the Notre Dame program before and after an event.

The two samples are then compared for TBI indicators, which include distorted vowels, hyper nasality and imprecise consonants. The systems has been validated independently by physicians in football and boxing matches. The testing was done in cooperation with James Moriarity, the University’s chief sports medicine physician, who has developed a series of innovative concussion testing studies.