Haroon Khan is a PhD student at the PhD Programme in Engineering Science.
30th of November 2023 at 10:00
Title: “Prospects and Challenges in EEG-fNIRS Hybrid Modality"
The candidate will defend his thesis at the 30th of November 2023 at 12:00
Webinar ID: 694 6934 8618
- First opponent: Maria Angela Franceschini, Professor/PhD, Martinos Faculty, Harvard Medical School, Main, USA.
- Second opponent: Hasan Ayaz, Associate Professor/PhD, School of Biomedical Engineering, Science and Health Systems, Drexel University, Philadelphia, USA.
- Leader of the evaluation committee/Chair of the committee: Rafael Borrajo, Associate Professor/PhD, Department of Mechanical, Electronics and Chemical Engineering, Faculty of Technology, Art and Design, OsloMet, Oslo, Norway.
- Leader of the public defence: Astrid Oust Janbu, Head of Department, Dept. of Mechanical, Electrical and Chemical engineering, Faculty of Technology, Art and Design, OsloMet, Oslo.
Main supervisor: Peyman Mirtaheri, Professor, Department of Mechanical, Electrical and Chemical engineering, Faculty of Technology, Art and Design, OsloMet, Oslo.
Gait and balance challenges refer to difficulty of walking or maintaining balance, often caused by neurological, musculoskeletal, or aging conditions.
Early detection and treatment of musculoskeletal conditions can help reducing healthcare costs worldwide.
However, research often investigates these conditions separately due to limitations in portable neuroimaging and the complexity of experimental setups.
A naturalistic setting should be used to study both gait and balance to understand the effect of simple factors such as barefoot walking, footwear, walking surface, and walking pattern on postural stability and brain activation.
The neurological perspective of these factors needs to be studied more, and further understanding is needed to understand human gait and balance fully.
From a brain activation perspective, it is also important to understand simple balance tests, such as Single-Leg Stance (SLS), the Infinity walks, Y-balance tests, and hop-stabilization tests.
Balance is not only related to the body’s biomechanics, but the brain also plays a significant role in its control. Therefore, a better understanding of motor control could significantly improve the balance of the human body and biomechanics.
This research aims to understand the motor control behind human gait and balance conditions. Also, whether using Functional Near-Infrared Spectroscopy (fNIRS) can detect cortical activity changes and connectivity changes in the motor areas in response to changes in gait.
In this thesis, we first aimed to understand the cortical activation and connectivity associated with the
effect of varying footwear and anti-pronated shoes.
The second part of the thesis examined the neurology behind prominent balance tests such as SLS, Dual-Leg Stance (DLS), and the Infinity Walk.
To test our hypothesis, we first evaluated the potential of existing portable neuroimaging modalities, specifically fNIRS and Electroencephalogram (EEG), for studying human gait and balance problems.
We then conducted experiments and collected data to investigate the effect of footwear, walking surfaces, anti-pronation shoes, the Infinity walk, and the single-leg stance.
After data collection, we analysed the data using existing and newly developed approaches in fNIRS, such as the General Linear Model and connectivity analysis, to understand cortical activation patterns, effective connectivity, and lateralization of motor control.
Results and Discussion
fNIRS is a promising technology to investigate human gait and balance in most naturalistic and dynamic settings compared to other modalities.
The barefooted walk has been shown to have several benefits, such as improved balance and proprioception, better postural control, reduced risk of chronic conditions, and balance.
In addition, from an energy expenditure perspective, we found optimal brain hemodynamics and connectivity while performing barefooted walks.
The barefooted walk can mark the baseline for cortical activation and balance control for many balance tests. Walking surfaces can significantly affect brain hemodynamics, as they can impact the level of cognitive and motor control demands.
For example, walking on different surfaces, such as uneven or unstable terrain, can require greater cognitive and motor control to maintain balance and stability. A rebounding mat can be a good alternative to enhance balance, motor learning, and neuroplasticity.
We did not find any statistically significant difference between pronating and anti-pronating shoes from both cortical activation and connectivity.
The reason might be that we need a better experimental setup to investigate these changes. We believe that pronation significantly affects postural stability, and it will cause differences in brain motor control.
Still, we need an improved and more focused experimental setup to distinguish these changes. The Infinity Walking patterns require greater attentional focus and coordination, which can lead to increased activation in the cognitive control regions of the brain.
The Infinity Walk is a good alternative for balance improvement in bilateral motor coordination. It has shown promise as a form of gait training that can help improve balance, stability, and brain hemodynamics.
From our understanding, SLS is a good test to investigate stability and leg dominance, and lateralization of motor control. Increased instability on one leg enhances cortical activation, particularly on the contralateral side. It can provide valuable information about the neural correlates of postural control.