If you have older sensors that do not auto ID manually set up the sensors 2 On

If you have older sensors that do not auto id

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If you have older sensors that do not auto-ID, manually set up the sensors. 2. On the Meter screen, tap Rate. Change the data-collection rate to 100 samples/second and the data-collection length to 30 seconds. Select OK. 3. Connect the Accelerometer to the reflex hammer using the cable tie, as shown in Figure 2. Place the Accelerometer cable toward the back of the hammer so it does not get in the way. 4. Have the subject sit comfortably in a chair that is high enough to allow his/her legs to dangle freely above the floor. 5. Attach two electrode tabs above one knee along the line of the quadriceps muscle between the knee and the hip. The tabs should be 5 cm and 13 cm from the middle of the patella (see Figure 3). Place a third electrode tab on the Figure 3 Figure 2
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Human Physiology with Vernier 14A - 3 Neuromuscular Reflexeslower leg. 6.Attach the red and green leads to the electrode tabs above the knee with the red electrode closest to the knee. Attach the black lead (ground) to the electrode tab on the lower leg. 7.Start data collection. If the graph has a stable baseline as shown in Figure 4, stop data collection continue to Step 8. If your graph has an unstable baseline, stop data collection and collect a new set of data by starting data collection again. Repeat data collection until you have obtained a stable baseline for 5 s. 8.Collect voluntary activation data. Note: Read the entire step before collecting data to becomefamiliar with the procedure. a.Have the subject close his/her eyes, or avertthem from the screen. b.Start data collection.c.After recording 5 s of stable baseline, swingthe reflex hammer briskly to contact the tableor other surface that generates a sound. d.The subject should kick his/her leg outimmediately upon hearing the sound. e.Continue obtaining reflexes (repeat parts cand d of this step) so that you record 5–10kicks during the data-collection period. 9.Determine the time elapsed between striking thetable surface with the reflex hammer and the contraction of the quadriceps muscle.a.To analyze the data, tap and drag across theEKG data to highlight the area from justbefore the table was struck to just after themuscle contraction.b.Choose Zoom In from the Graph menu.c.To examine the data pairs on the accelerationgraph, tap any data point. As you tap each datapoint, the acceleration and time values aredisplayed to the right of the graph.d.Tap the first high peak (which corresponds tothe first kick) on the acceleration graph(Figure 5). This peak indicates the time atwhich the table surface was struck. Record thistime in Table 1. e.Tap the first high peak (Kick 1) on the EMG graph. This peak indicates the time at which the quadriceps muscle contracted. Record this time in Table 1.f.Choose Autoscale Once from the Graph menu.g.Repeat this process of zooming in and determining the time of the hammer strike and reflex for a total of five stimulus-kick pairs.h.Calculate the change in time between the hammer strike and reflex for the five stimulus-kick pairs and then calculate the average change in time for all five pairs. Record the values in Table 1.Figure 5Figure 4
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  • Spring '14
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  • quadriceps muscle

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