Question

3. Describe the combined roles of vision and the vestibular apparatus in a coordinated behavior. Some examples could include performing a dance, playing a musical instrument (especially with others), playing a video game, walking on a balance beam, climbing a tree, performing a pole vault, or a turnaround jump shot. What are the differences and similarities in the roles of the two senses?

Answer 1

Vision is the ability to see. Vestibular apparatus consists of Semicircular canals, utricle, and saccule (macula), ampullae (crista), vestibular ganglion. The vestibular receptor is located in the inner ear next to the auditory cochlea, it is the balance mechanism that works in coordination with the visual system muscles and joints.

Cerebellum acts as the body’s movement and balance control center; it joins the spinal cord at the back of the head, which connects the lower part of the body to the brain. The vestibular receptors detect the rotational motion, linear motion and tilt of the head in relation to the gravitational force. It sends signals to the brain. Cerebellum receives the message of body positioning through the visual system, vestibular system, joints, and muscles.  

The position feedback to the cerebellum through the inner ear.

There are three semicircular in the inner ear each has a different orientation to detect. The movement of the head makes the fluid present in the semicircular to move that stimulates the tiny hair present in the ampullae (space where the semicircular canal ends) it sends the message to the cerebellum through the vestibular nerve.

At the same time, saccule and utricle (these are otolith organs that sense gravity and linear acceleration) that contain small crystals get displaced by the head movement and stimulate the tiny hair that transmits the message through a vestibular nerve to the cerebellum.

The position feedback to the cerebellum through vision

The vestibular system works with the vision system, consist of eyes, muscles and the parts of the brain that together help us to see. It helps in bringing awareness of body movements like walking, running, and riding.

Together with this, the sensors in the skin, joints, and muscles send the information to the brain about body positioning in relation to each other and in relation to the environment.

With these inputs, the brain signals back the body muscles and joints to adjust to keep the balance of the body and maintain coordination with the other parts of the body.

That means the brain receives the message from the eyes (visual input), inner ears (vestibular system), and muscles and joints (proprioceptive input), these three systems give the brains the awareness of the body position and in return, the brain instructs the vision, ears, and joints and muscles to act in coordination to keep the body balance and movement in relation to the gravitational force.

For example, walking on the balance beam: we have seen the child who does walking on the balance bean either keep a stick in his hand or spread his hand in order to adjust the body to the gravitational force. It is important to have the coordination between the vision, body movement and balance. The spreading of hand or a stick helps the child to maintain the center of gravity to the center of the body so that while walking on the beam he can maintain his balance. The child does not move his head frequently, he keeps it straight, because by moving his head the child can lose his balance and fall down. To maintain the balance coordination between vision, muscle and joints is important.