Neurophysiology Flashcards
Where does the lateral corticospinal cross?
midline in the ventral medulla pyramids
Where does the ventral corticospinal tract cross?
It crosses at the level of the spinal cord where they will synapse onto a lower motor neuron
Where are lower motor neurons?
Spinal cord
Where are upper motor neurons located
brain
motor cortex
What does the extrapyramidal system function to do?
Control posture
control head & eye movements
Regulation of muscle tone
Alternative motor pathway
What does the basal nuclei function to do?
initiating movement
selection of motor response
eye movements motivation
What does the reticular formation function to do?
regulating alertness & consciousness
What does the vestibular nuclei function to do?
information about head position and movement/acceleration
What does the cerebellum function to do?
motor coordination
What does red nucleus function to do?
Control gait
Where are the basal nuclei located?
telencephalon and mesencephalon
Where are reticular formation located?
Medulla, pons, midbrain
What happens if there is damage to an upper motor neuron?
Muscle weakness/partial paralysis
paralysis
increased muscle tone
What happens if there is damage to an lower motor neuron?
Paralysis
decreased muscle tone
What happens if there is damage to the pyramidal tract section?
Muscle weakness or partial paralysis
decreased muscle tone
What are the characteristics of a motor unit?
one alpha motor neuron + all the innervated muscle fibers
Fine control
each muscle fiber is innervated by just one motor neuron
What are the characteristics of a motor pool?
All the alpha motor neurona & all other motor neurons
What cranial nerves are located in the telencephalon?
CN 1: olfactory
What cranial nerves are located in the diencephalon?
CN 2: optic
What cranial nerves are located in the Mesencephalon?
CN 3: Oculomotor
CN 4: Trochlear
What cranial nerves are located in the metencephalon?
CN 5: Trigeminal
What cranial nerves are located in the Myelencephalon?
CN 6-12
Abducent
Facial
Vestibulocochlear
Glossopharyngeal
Vagus
Spinal Accessory
Hypoglossal
What is cranial nerve 5 and what is its function?
Trigeminal
Sensory to the face
Muscles of mastication
What is cranial nerve 7 and what is its function?
Facial
Sensory to ear
motor to muscles of facial expression
What is cranial nerve 9 and what is its function?
Glossopharyngeal
Sensory & motor to mouth and throat
What is cranial nerve 10 and what is its function?
Vagus
Sensory and motor to the viscera
What is cranial nerve 11 and what is its function?
Spinal accessory
motor to neck muscles
What is cranial nerve 12 and what is its function?
Hypoglossal
Motor to muscles of tongue
What are the function of the somatic nervous system?
Conscious sensation & voluntary movement
What are the effector organs of the somatic nervous system?
skeletal muscle
What are the motor pathways of the somatic nervous system?
one neuron, cell body in the CNS
What are the functions of the autonomic nervous system?
visceral sensation
cardiac & smooth muscle contraction
gland secretion
What are the effector organs of the autonomic nervous system?
smooth muscle
glands
cardiac muscle
What are the motor pathways of the autonomic nervous system?
two neurons that synapse outside the CNS
What are the functions of the parasympathetic nervous system?
Rest and digest functions
Where are the ganglion of the parasympathetic nervous system located?
near target organ
What are the two pathways in the parasympathetic nervous system?
Preganglionic and postganglionic neuron
Where are the
cell bodies in the preganglionic neuron located?
Synapses?
neurotransmitter?
receptor?
cell bodies in the brain & sacral spinal cord
synapses in ganglia near target organ
neurotransmitter acetylcholine
Receptor + nicotinic
Where are the
cell bodies in the postganglionic neuron located?
Synapses?
neurotransmitter?
receptor?
cell bodies in parasympathetic ganglia
Synapses on effector organ
neurotransmitter: acetylcholine
Receptor: muscarinic
What are the functions of the sympathetic nervous system?
fight, flight, fright
Where are the ganglion of the sympathetic nervous system located?
sympathetic chain next to the spinal cord but outside of the vertebra
What are the two pathways in the sympathetic nervous system?
Preganglionic and postganglionic neuron
Sympathetic nervous system
Where are the
cell bodies in the preganglionic neuron located in the?
Synapses?
neurotransmitter?
receptor
cell bodies in intermediolateral cell column
synapses in sympathetic ganglion
Neurotransmitter: acetylcholine
Receptor: nicotinic
Sympathetic nervous system
Where are the
cell bodies in the postganglionic neuron located in the?
Synapses?
neurotransmitter?
receptor?
cell bodies in sympathetic ganglion
synapses on effector organ
Neurotransmitter: norepinephrine
Receptor: alpha or beta adrenergic
What is the role of the adrenal gland in the nervous system response?
releases epinephrine and norepinephrine in to the blood
What are the length of the motor neurons in the sympathetic nervous system?
Short preganglionic
long postganglionic
What are the length of the motor neurons in the parasympathetic nervous system?
long preganglionic
short postganglionic
What is the location of the enteric nervous system?
located in the wall of the intestine
What is the function of the enteric nervous system?
regulates peristaltic contractions
How does the sympathetic and parasympathetic nervous systems effect heart rate?
Sympathetic: increases rate of depolarization and increases calcium influx in smooth muscle to increase contraction force
Parasympathetic: decreases rate of depolarization
How does the sympathetic and parasympathetic nervous systems effect blood pressure?
Sympathetic: contraction of smooth muscle in vessels to the GI tract and relaxation of smooth muscle in vessels to skeletal muscle
Parasympathetic: contraction of smooth muscle in vessels to skeletal muscle and relaxation of smooth muscle in vessels to GI tract
How does the sympathetic and parasympathetic nervous systems effect respiration?
Sympathetic: increases rate of respiration & relaxes smooth muscle in bronchioles
Parasympathetic: decreases rate of respiration & contracts bronchiolar smooth muscle
