Sierra Carangio
Neuromuscular Lab Report
Anatomy and Physiology
Spring 2011
D.Moore
Neuromuscular Reflexes
Introduction:
A reflex is your muscles response to a stimulus. In this lab you are going to test
the reflex of your patellar tendon, what you will be doing is using a reflex hammer to tap the
patellar tendon which will cause the quadriceps muscle to contract and your leg to extend. The
nerve impulses travel from your muscle to your spinal cord and back. A reflex can be reinforced
by small voluntary of other muscles than just your patellar tendon. Below you will find a
diagram to give you a better idea of what is going to happen.
Materials:
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A Computer
Vernier Computer Interface
Vernier Logger Pro
Vernier EKG sensors
Electrode Tabs
A Reflex Hammer
A Pen to Mark The Patellar Tendon
And a Pencil (Optional) for charting data
Procedure:
1. Connect EKG sensors to the computer interface.
2. Open “14B reflexes without ACC” in the human physiology with Vernier
folder.
3. Have the participant sit in a high chair or on a table so that his/her legs can
dangle freely f the edge.
4. Attach two electrode tabs above the knee along the line of the quadriceps
muscle. The tabs should be 5 and 13 cm from the center of the patella. The
third electrode should be placed on the lower leg.
5. Locate the patellar tendon by feeling for a narrow band of tissue that
connects the lower part of the patella to the tibia. Put a mark in the center
of your tendon with a pen.
6. Attach the red and green leads to the electrodes above the knee. Attach the
black lead to the electrode tab on the lower part of the leg.
7. Click collect to begin collecting your data. Record a baseline for 5 seconds
and continue to step 8
8. Collect patellar reflex data with and without reinforcements. Read entire
step before collecting the data:
a. Have the participant avert their eyes from the computer
b. Beginning collecting the Data
c. After recording a baseline for 5 seconds tap the mark on your
classmate’s tendon. If there is no visible reflex aim to other areas
around the mark.
d. After you have received 5-6 good reflexes have you classmate then
hook his/her hands together with the elbows facing out and pull
your arms away from one another at chest level.
e. Continue taking the reflexes until data collection is completed. 1015 reflexes should appear on the graph.
9. Determine the average amplitude of the reinforced and unreinforced
reflexes.
a. Click the statistics button
b. Move the bracket from the increased area in the run
c. Record the minimum and maximum value along with the change
between the two. Place this data in the table
d. Close the statistics button and repeat for 5 unreinforced and 5
reinforced arches
e. Next determine the average amplitude of the reinforced and
unreinforced events.
DATA:
Table 1
Reflexes without Reinforcements
Reflexes with Reinforcements
Reflexes
Response
1
2
3
4
5
Average
Values
MAX
(mV)
1.14
1.16
2.03
1.27
1.55
Halfamm
lllllllllllll
MIN
(mV)
.94
.9
.8
.7
.83
Halfamm
lllllllllllll
Change in
mV
.2
.26
1.23
.57
.72
.596
MAX
(mV)
1.11
1.86
1.09
1.93
1.41
Halfamm
lllllllllllll
MIN
(mV)
.96
.79
.9
.78
.75
Halfamm
lllllllllllll
Change in
mV
.15
1.07
.19
1.15
.66
.644
Analysis and Conclusion:
Throughout this experiment you are able to see how reinforced and unreinforced reflexes
differ. With reinforcements more signals travel to your brain but without the reinforcements they
only travel to your spinal cord and come back. Without reflex reinforcements there are less nerve
fibers are stimulated. This experiment show how reflex arches work while making it fun for you
and your classmates.