THE “6TH SENSE”: OUR VESTIBULAR SYSTEM
Have you ever tripped on something and righted yourself mid-fall? It might be a common, everyday sort of occurrence, but how commonly an event occurs does not diminish how remarkable it is. Do you often consider how truly amazing your sense of balance is? Its speed, its precision, and its accuracy (most of the time) is worth understanding and celebrating.
For an example of how truly incredible your sense of balance is, consider this: innovators in robotics from Boston Dynamics have only just this year created a robot that can walk like a human being without requiring a support beam or without significantly slowing its gait. Among designers, bipedal (two-legged) gait is among the most challenging parts of creating a human-like robot—that’s why many contemporary robots tend to resemble spiders or have tank treads.
Our vestibular sense contributes some of the information the brain needs in order to maintain our sense of balance, alongside our vision and proprioception. Our vestibular sense is the product of the vestibular apparatus in the inner ear. This system sends information to the integration centers in the brainstem and to the cerebellum.
The vestibular apparatus of the inner ear detects all motions of the head. Rotational, side-to-side, vertical, and horizontal movement is all detectable through a finely-tuned and sensitive system. The brainstem makes sense of the head’s movements through the inner ear receptor signals, combining it with the body’s position and visual information to create a full understanding of the body’s balance—allowing it to make corrections to the motor impulses being sent from the frontal lobe.
For such a vital system, the apparatus itself depends on fairly basic physical laws. The structure of the vestibular system is shaped into 3 semicircular tunnels, or “canals.” Each canal corresponds to a different plane (side-to-side and up-and-down). Each of these canals are filled with fluid, within which are tiny hair cells—a structure known as the cupula.
Imagine holding a bowl of cereal and quickly rotating it from side to side. The way the milk within the bowl moves counters the motion of the bowl itself—in the same way, the fluid in your canals moves and responds to the movement of your head.
Here’s where the structure becomes truly remarkable: the hair cells, based on the pressure or force applied to them, transduce their mechanical position into electrical signals. These signals are then sent to the brainstem. Through a simple mechanism involving fluid and hair cells, your brain is able to detect the movement of the head within milliseconds.
This structure makes some balance issues easier to explain. For example, when you’ve been spinning in a circle, the momentum will make the fluid in your ears continue to spin even when your body has stopped moving. The disconnect between your body’s stillness and the continuing signals of rotation to your brain is the sensation we call “dizziness.”
Signals about the position of the head also affect eye position. This is known as the vestibulo-ocular reflex (VOR), and it ties your vestibular signals to your visual ones. Essentially, when your head moves, the vestibular apparatus will automatically signal the eyes to move in the exact opposite direction with corresponding distance.
This reflex allows you to rotate your head while keeping your eyes focused on the same object. The VOR is crucial because your head is often moving constantly by small measures. It equips us with stable vision, which is especially vital for activities like reading, which requires a great deal of stability and focus. In fact, one of the most commonly injured reflexes in concussions is our VOR.
In order for your vision to adapt to new head movements effectively, the signals from your inner ear to your eyes would have to travel almost immediately. As a matter of fact, your eye muscles and the canals of the inner ear are separated by only three neurons. Researchers consider your VOR the oldest and fastest reflex in the brain—it occurs 100 times faster than the blink of an eye. Interestingly, the VOR does not depend on visual input. Even in the dark or with your eyes closed, your eyes will naturally remain oriented in the same direction when your head moves.
Remember, the brain’s primary role is to receive information, process it accurately, and create a suitable response. For our patients, their issues of balance are a result of the brain’s ineffectiveness or inability to process receptor information correctly. By using targeted therapies that stimulate the receptors of the three “balance” systems—visual, vestibular, and joint position—neuroscience specialists can correct or strengthen neural pathways within different areas of the brain.
Because the vestibular sense and the ocular muscles are so tightly integrated when it comes to balance, the vestibular sense can be affected through exercises that pair eye and head motions together. In addition, rotational movement has been effective at stimulating your sense of balance, helping correct issues in the processing between the frontal cortex, brainstem, and vestibular apparatus.
Plasticity Brain Centers utilizes cutting-edge technology and diagnostic tools that utilize the well-established scientific principle of neuroplasticity. While neuroplasticity is a decades-old idea in neurological research circles, only leading-edge treatment centers have begun to apply it in a clinical setting.
One of the pieces of cutting edge technology that we utilize is the MARC, which stands for Multi-Axis Rotational Chair. The MARC is able to perform rotations in 3 axes of movement: forward and backward, left and right, and side to side. The MARC is used to help stimulate areas in a person’s brain that are not functioning to their optimum levels.
This stimulation helps create new connections and repair damaged areas to allow the individual to better understand where they are in their environment. This stimulation can be part of the therapy plan that helps individuals who have suffered an injury or a degenerative condition, but it can also help someone looking to improve their performance. The MARC can be a powerful tool to improve brain function when prescribed by our highly trained clinicians.
As the premier ReceptorBased™ clinic, Plasticity Brain Centers is employing the therapies taught by the Carrick Institute. Plasticity Brain Centers utilizes sensory integration therapies to aid in the rehabilitation of neurological injuries and promote human performance enhancement. Contact our team today for more information about how we can help.