Physical Therapy questions and answers
2024
Reticular Formation - - Extends vertically -> brain stem
- Level of arousal (sleep/wake cycles)
- Motor responses to maintain homeostasis
- Modulation of muscle tone
Spinal Cord - - Provides communication b/w brain and peripheral nerves
- From medulla -> L1-L2
- Enlargements = cervical + lumbar
- Conus medullaris = L1
- Cauda equina = nerve roots from L2-S5
Dorsal vs. Ventral Horn - DA = dorsal afferent
VE = ventral efferent
Muscle Spindle - Sensory organ that senses stretch in muscle
Deep tendon reflex - Rapid stretch stimulates muscle spindle causing reflex contraction
of that muscle (muscle contraction does not require cortical input)
Reciprocal Inhibition - Activation of muscle spindle inhibits opposing muscle
Golgi Tendon Organ - Senses tension within a muscle whether it is being stretched or
contracted
Automatic Inhibition - - Activation of GTO during muscle contraction causes automatic
reflex relaxation AKA automatic inhibition
- Activation of the GTO during stretch by performing a low force stretch for >7 seconds
causes inhibition of muscle spindle allowing deeper stretch
- Autogenic inhibition can be induced by contracting a muscle right before it is passively
stretched
Upper Motor Neurons - Motor neurons that synapse above the anterior horn (spasticity,
hyperreflexia, Babinski reflex, clonus)
, Lower Motor Neurons - Motor neurons that synapse at or below the anterior horn
(Flaccidity, marked atrophy, fasciculations, hyporeflexia)
PNS - - Autonomic: Involuntary (sympathetic, parasympathetic)
- Somatic (Body): Voluntary (cranial nerves - brain stem) (spinal nerves - sensory:
dermatomes, motor: myotomes, plexuses)
Cervical Plexus - Anterior Rami of C1-C4 (innervates levator scap. trapezius, and SCM.
Phrenic nerve: innervates the diaphragm)
Brachial Plexus - Anterior Rami of C5-T1 (5 primary nerves, provides sensory and
motor innervation of UE - innervates pec maj. subscap. and lat. dorsi)
Lumbosacral Plexus - Anterior Rami L1-S3 (6 primary nerves, innervates thigh, lower
leg, & foot)
Common Carotid Arteries - (Anterior cerebral circulation) split into the external supplies
of the face and internal carotids
Internal Carotids - Supply frontal/parietal lobes, p/o temporal and occipital lobes, optic
nerves and retinas. Split into left and right anterior and middle.
Middle Cerebral Artery - Largest and most efficient occluded. Supplies lateral surface of
brain. Deep parts of frontal and parietal lobes.
Anterior Cerebral Artery - Supplies superior border of frontal and parietal lobes.
Major components if the nervous system? - - CNS
- PNS
- Nerve cell types (neurons, neuroglia)
- Structures of neurons (axon, dendrite, cell body)
- Neurotransmitters and synapses
- Axons (myelinated/unmyelinated) and tracts
- Gray matter
- White matter
- Supportive and protective structures
- Vascular supply to the brain
What does the nervous system do? - - Organized communication system
- CNS and PNS
- Nerve cells -> receive, transmit, analyze, communicate information
- Electrochemical impulses travel -> nerve fibers and tracts
- FNS -> perceive sensation, initiate movement, process information
Types of Neurons - - SA - sensory, afferent = receive sensory input from periphery and
transmit to CNS