EMG- Chewing Lab
I. Title: Electromyogram Chewing Lab
II. Purpose: To associate the amount of electrical activity with the strength of muscle contraction, and to compare the masseter muscle function during different types of chewing activity.
III. Hypothesis: If different types of foods are chewed, then the foods that are harder with cause the electromyogram of the masseter muscle to increase because the masseter has to work more in order to chew harder foods.
- Foods: Chips, Pudding, Soda ( with s straw), Cookie, Banana, Peanut Butter, Ice Cream, Beef Jerky, Carrots, Celery
- Vernier Computer Interface
- Logger Pro
- Vernier EKG Sensor
- Electrode Tabs
- Set up the computer and connect all the Vernier equipment.
- Prepare all food.
- Place electrode tabs on the upper check, lower jaw, and the arm.
- Attach the red and green leads to the tabs on the face, and the black one to the tab on the arm.
- Relax the jaw for five seconds while recording the EKG.*
- Clench the jaw for five seconds while recording the EKG.
- Repeat step five, but after the five seconds chew the different foods while continuing to record the EKG.
- After all foods are recorded, analyze the data to find the Δ mV for each food, and compare among all foods.
* It will be easiest if you save every recording under a different file. This will allow you to have a separate file for each food chewed.
VI. Data: Graph shows Δ mV for each food and clenching of the jaw.
After analyzing the data, my hypothesis proved to be correct. Harder foods resulted in a greater Δ mV in the masseter muscle than softer foods. Therefore, I can conclude that there is greater amounts of electricity in the contraction of the muscle when chewing harder food because more work is required.
This lab enhanced my knowledge about the masseter muscle, and why exactly there is higher amounts of electrical activity when chewing harder foods. I learned that the masseter is one of four muscles that produce chewing movements and that it is a thick, flattened muscle that can be felt in front of the ear when clenching ones teeth. I also learned that the amount of electrical activity in a muscle directly correlates with the strength of the muscle contraction. Therefore, I was able to conclude that in order to chew harder foods the masseter had to contract harder, which results in increases in electrical activity.
NOTE: Although I didn’t follow this experiment exactly, you may look at the
“true” experiment document by clicking Introduction to EMG Lab.