Lab 8 Nerve Flashcards
Equipment required for this lab?
- EM-220 Event marker
- IXTA, USB cable, IXTA power supply
- Computer
How to set up the event marker
Plug connector to EM-220 event marker into the EM1 Channel input on IXTA
What is ex 1 called
RXN TIME and VISUAL SIGNALS
What is the aim of ex 1
To MEASURE the RXN TIME of a SUBJECT to a VISUAL SIGNAL
Procedure for exercise 1 rxn time and visual signal
- Subject sitting on chair in front of comp
- Subject will watch right side of comp screen and press EM-220 event marker when signal (BLACK LINE) appears on comp screen
- Another student outside of subject’s sight should prepare to quietly press and release F1 key to generate the black line. Signals should not be less than 3 seconds nor more than 6 secs apart
- Perform 10 TRIALS
What is ex 2 called
RXN TIME and AUDITORY SIGNALS
Aim of ex 2
To MEASURE the RXN TIME of a SUBJECT to an AUDITORY SINGAL
Procedure for ex 2 rxn time and auditory signals?
- COVER comp screen to prevent subject from seeing any signal on screen as a visual signal OR have subject turn away from screen OR close their eyes
- Subject sit in chair near comp, but should not see screen.
- Tell subject to press EM-220 event marker when they hear signal
- Out of subject’s sight, another student prepare to LOUDLY tap (so subject can hear) and press and release F1 key on keyboard to generate black line on screen.
- Press F1 key loudly 10 times (10 auditory signals). They should not be less than 3 seconds and no more than 6 seconds apart
Equipment required for ex 3 achilles tendon reflex
- B3G ECG cable and electrode lead wires
- Disposable EMG electrodes
- PRH-200 patellar reflex hammer
- Measuring tape
What is ex 3 called
ACHILLES TENDON REFLEX
Aim of ex 3 achilles tendon reflex
To DETERMINE the CONDUCTION TIME from TENDON TAP to RESPONSE of the GASTROCNEMIUS MUSCLE in the ACHILLES TENDON REFLEX ARC
Time for ex 3
20 mins
Procedure for ex 3 achilles tendon reflex
- Clean w/alcohol 3 regions on CALF of LEFT leg for electrode attachment. One area near ANKLE, second is in the MIDDLE of CALF muscle, and third area ~8cm BELOW BACK OF KNEE.
- Apply electrodes to cleaned areas
- Attach 3 colour-coded electrode leads onto disposable electrodes so that
- RED (+1) lead to electrode near BACK of KNEE
- BLACK (-1) lead to electrode MIDDLE of CALF muscles
- GREEN (C) lead wire to electrode on ankle that fxns as GROUND - Subject SIT on lab BENCH so thighs are supported by top of bench and CALVES HANG FREELY
- Tap achilles tendon with POINTY END of reflex HAMMER a few times to locate point on tendon that produces consistent contraction of gastrocnemius muscle and downward movement of foot (plantar flexion)
- Click record. Instruct subject to move foot up and down to demonstrate the EMG that occurs w/plantar flexion and dorsiflexion.
- TAP ACHILLES TENDON to elicit stretch reflex.
- Record 5 TRIALS with same tapping force
Conduction velocity eqn?
Conduction velocity (m/s) = total path length (mm) / [mean reflex time(ms) - 0.5ms]
What is ex 4 called
Patellar tendon (knee jerk) reflex
Aim of ex 4 patellar tendon (knee jerk) reflex
To determine CONDUCTION TIME from TENDON TAP to RESPONSE of QUADRICEPS MUSCLE in PATELLAR TENDON REFLEX ARC
Time for ex 4
20 mins
Procedure for ex 4
- Subject sit on bench so thighs suspended on top of bench and calves hanging freely
- Clean w/alcohol 3 regions on THIGH of LEFT leg for electrode attachment. One area near KNEE, second is in the MIDDLE of THIGH muscles, and third area ~8 inches above the second
- Apply disposable electrodes to cleaned areas.
- Attach
- BLACK (-1) LEAD to electrode ~12cm from KNEE
- RED (+1) LEAD to electrode 8cm above black electrode, thus 20cm from knee
- GREEN (C) lead to electrode on knee and fxns as GROUND - Feel position of PATELLAR TENDON BELOW KNEECAP. Place one hand on patellar tendon and other hand to tap tendon w/reflex hammer. Find point on tendon that causes greatest response from QUAD muscles
- Record. Then ask subject to raise his lower leg to demonstrate EMG that occurs during QUAD contraction and relaxation
- Subject RELAX QUADS as exercise begins
- Subject perform JENDRASSIK MANEUVER so they don’t anticipate tap. Tension in quads = nosy EMG
- Tap subject’s patellar tendon to elicit stretch reflex
- Record 5 TRIALS using same tapping force
What is the jendrassik maneuvar
Close eyes, grasp hands together at middle of thorax, and contract isometrically as if trying to pull hands apart
- raises lvl of activation of CNS
Equipment for ex 5
- iWire-B3G cable and EMG lead wires
- 7 disposable snap electrodes
- HV stimulator lead wires
- FT-220 hand dynanometer
- Tennis ball
Set up steps for person A
- Remove all jewelry from right arm
- Clean areas where electrodes attached
- Obtain 3 disposable electrodes
- Locate areas on FOREARM; place electrodes over these locations and attach coloured recording leads
- BLACK (-1) electrode below CREASE OF ELBOW, slightly LATERAL of MIDLINE
- RED (+1) electrode on MID-FOREARM, slightly LATERAL
- GREEN (GROUND) btwn red and black electrodes - Person A should hold TENNIS BALL or squeezable object
Set up steps for person B
- Obtain 2 disposable electrodes
- Clean inside WRIST of NON-DOMINANT ARM w/alcohol
- Snap ends of H.V. Output lead wires onto electrodes so that
- RED (+1) lead snapped onto electrode on LATERAL EDGE of INSIDE of WRIST
- BLACK (-1) lead snapped onto electrode on MEDIAL EDGE of INSIDE of WRIST - Person B lightly cup FT-220 hand dynanometer in palm of their hand, trying not to hold on to it too tightly (just resting in their grip)
What is ex 5 called
Human to human muscle control
Aim of ex 5 human to human muscle control
to determine the EFFECT of a “SQUEEZE” by Person A on Person B’s response
Time for ex 5
30 mins
Procedure for ex 5
- Person A hold tennis ball in hand. Lay hand on bench with PALM UP. Not squeezing ball, their hand and forearm COMPLETELY RELAXED.
- Person B sit quietly with hand lightly cradling hand dynanometer. Use slight pressure from fingers to hold sensor.
- Person A squeeze ball or curl hand towards wrist. QUICK, FIRM RXN
- Person A squeeze ball or flex hand 5 TIMES. Person B should have a response each time person A flexes or squeezes.
