JOAN BANKS-SMITH: 00:08
I'm Joan Banks-Smith for Kessler Foundation's Fast Takes. Research that changes lives. In this episode, Dr. Vikram Shenoy Handiru, associate research scientist in our Center for Mobility and Rehabilitation Engineering Research, talks about his peer-reviewed article Graph-Theoretical Analysis of EEG Functional Connectivity During Balanced Perturbation in Traumatic Brain Injury, a pilot study. This was epublished on July 26, 2021, in the journal Human Brain Mapping. Funding Source was the New Jersey Commission on Brain Injury Research. Dr. Handiru, can you share with us the main takeaways of this study?

VIKRAM SHENOY HANDIRU: 00:53
A little background. So the postural instability or the inability to maintain proper balance while standing or walking is a major complication of traumatic brain injury. This inability limits the independence of TBI survivor and compromises the safety. Unfortunately, we still don't know much about what are the underlying mechanisms in the brain responsible for this loss of balance. Therefore, in this paper, we present the study trying to investigate the changes in the brain connectivity in response to balanced perturbation. So when I say balance perturbation, it means a random push or pull effect that one can feel when they're standing on a platform. To be more specific, the goal is to study the brain connectivity patterns in terms of what we call functional integration and functional segregation. The idea is that when there is an external sensory cue in terms of balance perturbation, different parts of the brain must communicate and coordinate with each other to maintain balance. The past research shows that when a healthy person is at rest or not doing any task, different brain regions are working in isolation. We call this as functional segregation. And when there is an external stimulus like balance perturbation, we believe all these different brain regions will come out of their isolated roles and start coordinating with each other for a proper response to an external stimulus, which we call functional integration. However, this type of behavior may not be found in a person with traumatic brain injury or TBI, as the damage to the brain might have impacted the connections between different brain regions. In our paper, we compare this brain functional connectivity changes during the task by recording the brain activity using EEG or electroencephalography in 17 TBI and 15 healthy controls.

SHENOY HANDIRU: 02:52
We also collected the neuroimaging data using an advanced MRI technique called diffusion tensor imaging, or DTI, which allows us to study the structure of the brain fiber connections. When there is, say, traumatic brain injury, there is a severe damage to a lot of brain fibers, which connect different parts of the brain. Specifically in the context of maintaining balance, let's say if the fiber track in the brain region called corpus callosum gets damaged, it significantly affects the balance. Therefore, we wanted to know whether the abnormal brain response shown by EEG activity patterns is related to the structural anomalies in the brain or the damage in the brain. So in our study, we noticed the EEG connectivity trend in TBI is correlated with the ability to maintain balance, meaning higher functional connectivity, betterment balance performance. And also, this is reflected in terms of the structural integrity of white matter fiber tracts in the brain.

JOAN BANKS-SMITH:: 03:57
What is the impact and next implications of this publication to the field?

SHENOY HANDIRU: 04:01
Using EEG based graph measures, in our study, we looked at the brain regions as a network of different regions or a graph composed of different brain regions. With this study, we were able to explore the differences in underlying structural and functional mechanisms in individuals with and without traumatic brain injury, which may lead to the identification of a neural biomarker for balance and betterment. Based on the preliminary findings we now know that the TBI affects the brain connectivity patterns. Also, we know how the healthy brain connectivity patterns look like. Going forward, we must try to find new ways of treatment where some of the damaged brain networks can be rewired. For instance, in another ongoing study, we are currently looking at the effect of balance training or a balance platform training on the brain connectivity patterns in TBI and to see whether after undergoing such training will help the TBI patients to regain some of the lost functional connections. Another potential intervention, or the implication, would be to improve the balance in TBI by stimulating the brain region responsible for balance control now that we know there are certain specific brain regions which are responsible for maintaining the balance.

JOAN BANKS-SMITH:: 05:32
To learn more about Dr. Handiru and his peer-reviewed article, links are in the program notes. Tuned into our podcast series lately, join our listeners in 90 countries who enjoy learning about the work of Kessler Foundation. Be sure and subscribe to our SoundCloud channel, Kessler Foundation, for more research updates. Follow us on Facebook, Twitter, and Instagram. Listen to us on Apple Podcasts, Spotify, SoundCloud, or wherever you get your podcasts. This podcast was recorded on October 20th, 2021 remotely and was edited and produced by Joan Banks-Smith, creative producer for Kessler Foundation.