2. OUTLINE
• Reflex
• Reflex arc
– Components of reflex arc
– Monosynaptic reflex arc
– Polysynaptic reflex arc
• Effector
• Conclusion
• Experimental Set Up
• Procedure
3. Reflexes
• A reflex is a rapid, involuntary response to a stimulus.
• A reflex arc is the pathway traveled by the nerve impulses
during a reflex.
4. • A reflex arc involves the following components, shown below;
5. • The receptor is the part of the neuron (usually a dendrite)
that detects a stimulus.
• The sensory neuron transmits the impulse to the spinal cord.
• The integration center involves one synapse (monosynaptic
reflex arc) or two or more synapses (polysynaptic reflex arc) in
the gray matter of the spinal cord.
6. Monosynaptic reflex
• A monosynaptic reflex is, typically, a reflex that does not
involve the brain.
• There is no association neuron in the spinal cord;
therefore, information does not go to the brain.
• An example of a monosynaptic reflex is the patellar
reflex, sometimes called the knee-jerk reflex.
7.
8. Polysynaptic reflex
• A flexor (withdrawal) reflex is a polysynaptic reflex that causes
a limb to be withdrawn when it encounters pain.
9. Polysynaptic reflex
• In polysynaptic reflex arcs, one or more interneurons in the
gray matter constitute the integration center.
• A motor neuron transmits a nerve impulse from the spinal
cord to a peripheral region.
10. Effector
• An effector is a muscle or gland that receives the impulse
from the motor neuron.
• In somatic reflexes, the effector is skeletal muscle.
• In autonomic (visceral) reflexes, the effector is smooth or
cardiac muscle, or a gland.
11. Conclusion
• The human reflexes, are the basic mechanisms of the
organism defense.
• They represents the capacity of the body fast reaction to the
environment stimulus.
• A good reflex is a measure of the organism functionality.
• The reflexes state is one of the organism performance
parameters.
12. Conclusion
• The fast reaction capacity to an external stimulus gives us an
essential information concern to the nervous system
functionality.
• The reflexes and the causes which affect them are studied by
the Physiology Discipline from Medical Science.
• There are the physicians and the scientists in the field of
medicine who need a new procedure to improve the reflex
test.
15. Procedure
1. Follow the uppermost rectangular curve with a felt tip pen
through the slit for one complete rotation ( jumps).
2. Increase the drum speed stepwise (5cm/s, 10cm/s and
20cm/s) and a fresh rectangular curve is followed through
one rotation at each step.
3. Repeat the experiment with the same test subject under
different environmental condititons (noise or drinking
alcohol)
16. Calculations
1. Calculate the Dead Time 3. Calculate the Mean Dead Time
(gives the Reaction Time)
2. Calculate the Follow-throug Time 4. Calculate the Threshold frequency
(Sum of the Reaction Time and
Mean Follow-throug Time)
