LAb 4 Human Reflexes Flashcards
Transmits the afferent impulse to cns
Sensory neuron
Either monosynaptic or polysnaptic region within cns
Integration center
Conducts efferent impulses from the integration center to an effector
Motor neuron
Muscle fiber or gland that responds to the efferent impulse
Effector
Synapses directly to motor neuron
Monosynaptic
Involve at least one interneuron in between sensory and motor neuron
Polysynaptic reflexes
Difference
Conduction time
Time consumed in peripheral nerve
Latent period
Portion of latency consumed in the cord
Nuclear delay
Reflex same side of body
Ipsilateral response
Other side of body response while the other is the stimuli
Contra lateral response
Subject sit on edge of desk with both feet off the floor. Using a hammer
Patellar reflex
Patella stretches what tendon
Quadriceps
Patellar reflex stimulates
Stretch receptors
Afferent impulse in sensory fiber of the femoral nerve leading to the
Lumbar and spinal cord
Patellar reflex is
Monosynaptic
Interneuron to relax antagonistic hamstring muscle
Inhibitory interneuron
What does patellar tendon tests
Function of femoral nerve and spinal cord segments L2-L4
Absence or decrease of reflex in patellar is called
Westphal’s sign
Set of fingers interlock into hook like form and out infront of Chest, pulling to opposite side
Jendrassik maneuver
Elicits a larger reflex
Jendrassik maneuver
Opposite of starch reflex
Contracts and activates Golgi tendon (proprioreceptor)
Golgi reflex
The activation of one muscle eight he simultaneous inhibition of firs antagonistic muscle
Reciprocal inhibition
Composed of 3-10 intrafusal muscle that lack myofilaments in central region and are non contractile
Muscle spindle
Type 1a fibers primary sensory. Type 2 fibers secondary sensory interested by
Gamma efferent fibers
Contractile Muscle fibers are innervated by
Alpha efferent fibers
Activating the motor neuron gives the muscle spindle the function to protect the skeletal muscles from over extending
Alpha efferent motor neuron
A contracted muscle may stay contracted because of
Alpha gamma interaction
Causes intrafusal fibers to contact
Alphas for neurons
Cause muscle spindle to contrac this relieving slack that the music espindle develops when the muscle is on contacting state
Gamma motor neurons
Also known as ankle jerk reflex
Achilles reflex
Occurs when Achilles’ tendon is tapped while the foot is Dorsi-reflex
Achilles reflex
What nerve root does Achilles check
S1-s2
Site of stimulation
Receptor
Jerking of the forearm occurs, tricep tendons hit with hammer.
Triceps Reflex
tricep reflex stimulates
C6-C7 reflex arcs
bicep brachii, jerking of the forearm
Biceps Reflex
bicep reflex stimulates
C5-C6
the arm is resting, jerking of forearm when the brachioradialis tendon is hit with hammer
brachioradialis reflex
brachioradialis reflex stimulates
C5-C6
Tapping on the forehead, primitive reflex
Glabellar Reflex
if blinking occurs persistently during glabellar reflex this condition is called (abnormality)
Myerson’s sign
afferent reflex is transmitted by the —- and efferent signals come back to oricularis oculi muscle via.. that causes blinking
trigeminal nerve— facial nerve
Glabellar reflex is often seen
Parkinson’s Disease
a finding elicited by a reflex test that verifies the presence and absence of prob in corticospinal tract also known as finger flexor reflex
hoffman reflex
upper limb equivalent of babinski’s sign
hoffman reflex
Babinski sign indicates a dysfunction at
upper motor neuron
hoffman is analogous to
spinal stretch reflex
test involves tapping the nail or flicking the terminal phalanx of the 3rd and 4th finger, positive sign with flexion of the phalanx
hoffman’s reflex
2 important neurological test
plantar and babinksi
stimulates which receptor
cutaneous receptors in the lateral aspect of the sole of the foot
normal sign.. causes the toes to flex and move closer together
plantar reflex
abnormal response, toes flare out and indicates damage to
pyramidal tract
babinksi sign
in bright light the circular muscles of the iris contract and the pupil constricts, controlled by parasympathetic
pupillary reflex
whether each pupil constricts when lighted up
direct pupillary reflex
whether each pupil constricts with light shone into the other eye
consensual pupillary reflex
convey information from the photoreceptors to the optic nerve which connects to the pretectal nucleus of the high midbrain
retinal ganglion
why assessing tests in both eyes important
test to check on brain stem function damage
lack of pupillary reflex can be caused by
optic nerve damage, oculomotor, brain death, depressant drugs, (barbituates)
test when eyelashes are touched
palpebral reflex
