Module 7 Flashcards
Axon
Projection transmit impulses Away from the cell body
Dendrites
Projections transmit toward the cell body
Terminal boutons
Tiny bulges at the end of axon that communicate with neurons, muscle fibers or glands
Myelin Sheath
Surround same axons and increase the rate of impulse transmission
Schwann Cell
Produce the Myelin sheath
Nodes of ranvier
Separate the Schwann cell
White matter
Bundles of myelinated nerves
Synapse gap
The gape between the neurons
Presynaptic terminal
Terminal bouton or similar
synaptic cleft
Space between neurons
Postsynaptic cell membrane
opposite ends of the presynaptic terminal
Afferent
Transmit impulse from sensory towards the CNS (brings info to the brain)
Efferent
Sends directions from your brain to muscles and gland
Somatic
Voluntary (skeletal muscle movement)
Autonomic
involuntary (keeps your heart beating, breathing etc.)
Sympathetic
flight or fight
Parasympathetic
Rest/digestive, relex
Electrical impulses
Neural impulses are generated by small ionic changes
Action potential
ability to create this charge
Resting potential
charge at rest
Meninges
Membranes that encase the CNS
Cerebrospinal fluid
The plasma-like liquid that fills the space between the arachnoid and the Pia mater layers provides additional cushion and support
Dura mater
is the outer and toughest layer
arachnoid layer
is the middle layer with a spider web-like vascular system
Pia mater
is the innermost layer
Neurons
Generate and transmit bioelectrical impulses
Neurons facts
- Do not divide
- Losses due to age and injury
- not all cell death results in loss of functioning
-undamaged neurons in the brain will assume functions of damaged neurons
Neurons facts 2
-severed brain and spinal cord axons can’t be repaired
-a spinal cord can result in paralysis and loss of sensation below the damaged area
-constant oxygen and glucose supply if not can be hypoxia and hypoglycemia
Electrical impulses steps
- protein gates open and sodium flows into the cell, increasing the charge called depolarization
- rapid outflow of positively charged potassium ions immediately following depolarization to return to resting potential
- impulses travel down the nerves, triggering the release of neurotransmitters from the presynaptic terminal
- the neurotransmitters cross the synaptic cleft only in one direction, to stimulate an electrical reaction in nearby neurons.
- electrical reaction passes through those neurons to the next synapse. then repeat
some neurotransmitters inhibit action potential
TRUE
At each synaptic transmission, a small burst of neurotransmitters is released and then either destroyed by enzymes or reabsorbed by the postsynaptic membrane to be recycled for the next transmission.
TRUE
How many cervical
8
How many Thoracic
12
How Many lumbar
5
How many Serum
5
How many coccyx
1
How many cranial nerves
12
Where do most nerve fibers pass through?
Most of the many nerve fiber pass through branches that terminate in the reticular formation
Reticular formation
Acts like a gatekeeper, receiving all incoming and outgoing information
How does the reticular formation sends impulses?
The reticular formation sends impulses to the cerebral cortex through specialized nerve fibers that make up the reticular activation system
What are the reticular formation and reticular activation systems responsible for?
The reticular formation and reticular activation system are responsible for alertness during the day and can prevent sleeping at.
Basal ganglia
plays a pivotal role in coordination, motor movement, and posture
Limbic system
Works with the hypothalamus to influence instinctive behavior, emotions, motivation, mood, pain, and pleasure.
Gyri
folds that increase the surface area.
Sulci
grooves between the gyro
Cerebrum facts
- Largest of the region
-controls the higher thought process
-surrounded by the cerebral cortex
-divided into R/L hemisphere
Cerebral cortex
Thin layer of gray matter
White matter?
lies beneath the gray matter and contains bundles of axons that transmit impulses from the cerebral cortex to the spinal cord. enhancing communication and coordination of activities
Frontal lobe
Voluntary motor activity and plays a role in personality traits
Parietal lobe
Receives and interprets sensory input with the exception of smell, hearing, and vision
occipital lobe
processes visual information
Temporal lobe
Hearing and memory
Motor
Stimulates muscle activity
Sensory
Receives and sensory information
Association
integrates information and initiates coordinated response
Thalamus
Receives and relays most of the sensory input, affects mood, and initiates body movements
Subthalamus
Participates in motor activities
Eithalamus
functions unclear
Hypothalamus
is the most inferior portion of the diencephalon that regulates many bodily functions
Brain Stem facts
-connects the brain to spinal cord
-crucial for many basic body functions
-injury can lead to death
-collaborates with hypothalamus to regulate vital activities
-main thoroughfare for info traveling to and from brain
-10/12 cranial never exit from the brain stem
Pons
Contains nerves that regulate sleep and breathing
Midbrain
the smallest region
-acts as a relay station for auditory and visual info and controls visual and auditory systems as well as eye movement
Where does the spinal cord exit?
exits the skull through the foramen magnum
Where does the spinal cord extends?
extends through the vertebral canal to L2
Anterior spinothalamic tract
A sensation of light, touch, pressure, tickling, itching
Lateral spinothalamic tract
allow the sensation of pain and temperature
Spinocerebellar tract
establish the body’s position relation to the cerebellum
Corticospinal tract
coordinate movements especially the hands
Vestibulospinal tract
responsible for involuntary movements
Reticulospinal tract
also responsible for involuntary movement
Spinal reflex arcs
process that creates an unconscious response to stimuli
Flexor reflex
Withdraw reflex in response to touching an unpleasant stimulus. Stimulus without conscious action
What tracts regulates impulses?
The tracts of the spinal cord and brain
Nerves
Bundles of nerve fibers each fiber is part of the neuron
How does nerves transport messages?
To and from the CNS
Ganglia
collections of nerve cell bodies outside of the CNS
Sensory nerves or afferent nerves carry impulses?
From specific part of the body to the brain
Dermatome
area of the skin innervated by a given pair of spinal sensory nerves
the motor nerves or efferent nerves carry impulses?
from the brain to the corresponding muscle receptor, resulting in muscle contraction and movement
interneurons
connect the sensory and motor neurons in the spinal cord
Plexus
several nerves intersecting to form an organized collaboration
plexuses located in the cervical
C1-C4
plexuses located in the brachial
C5-T1
plexuses located in the lumbar
L1-L4
plexuses located in the sacral
L4-S4
Autonomic
-controls smooth muscle
- unconscious response that affects activities like HR, BP, and intestinal motility
Alterations may result in
- impaired physical mobility
- chronic pain
- impaired social interaction
-incontinence
-Risk for injury - self-care deficit
Congenital neurologic disorders
- Hydrocephalus
-Spinal Bifida
_ Cerebral palsy
Infectious neurologic disorders
- meningitis
- Encephalitis
- Zika virus disease
Traumatic neurologic disorders
-Brain injury
- spinal cord injury
Vascular neurologic disorders
- Transient Ischemic attack
- Cerebral vascular accident
- Cerebral aneurysm
Chronic degenerative disorders
-Multiple sclerosis
- Parkinson disease
Amyotrophic lateral sclerosis
-Myasthenia gravis
- Huntington’s disease
Dementia
-Alzheimer disease
-Creutzfeldt-Jakob disease
-AIDS dementia complex
Cancers of the nervous system
Brain tumors
Hydrocephalus
Excess CSF accumulation within the skull
- may present at birth or develop later in life
Hydrocephalus types
-CSF flow disruption
-noncommunicating or obstructive
Hydrocephalus manifestations in infants
-unusually large head
-rapid increase in head size
- bulging fontanel
-vomiting
lethargy
- irritability
-high-pitched cry
-feeding difficulties
-seizures
-eyes that gaze downwards
-development delay
Hydrocephalus manifestations in adults/older children
-headache followed by vomiting
-nausea
-blurred vision or diplopia
-sluggish pupil response to light’
-eyes that gaze downward
-uncoordinated movements
-extreme fatigue
-slow/regression of development
-memory loss
-confusion
-urinary incontinence
-irritability
-personality changes
-impaired Performance in school/work