Neuro - Nervous System Flashcards
What system has involuntary activity
Autonomic Nervous System
What system is voluntary
Somatic Nervous System
What protects the brain
The skull
Meninges
Cerebrospinal Fluid (CSF)
What are the 3 connective tissue membranes in the Meninges
Dura Mater
Arachnoid Mater
Pia Mater
Dura Mater
Outer Layer og meninges
Tough, fibrous, double layered membrane
Forms dural sinuses
What does the dural sinuses do
collect venous blood and CSF for return to the general circulation
Subdural Space
lies beneath the dura
normally empty, can fill with blood after an injury
Arachnoic space
Middler Layer
Losose web like covering
Sub Arachnoid space
contains CSF, cerebral arteries and veins
lies below arachniod
Pia Mater
Inner Layer
delicate connective tissue
contains many small blood vessels
CSF
cerebral spinal fluid
priced cushion for the brain and spinal cord
circulates around the brain and eventually returns to the venue sblood
maintain normal pressures (ICP)
What is a Blood Brain Barrier
Protective mechanism
limits the passage of potentially damaging materials
Cerebral Hemispheres
make up largest portion of brain
2 hemispheres separated by a fissure
what are the 4 major lobes in the hemisphere
Frontal
Parietal
Occipital
Temporal
What does the dominant hemisphere control?
Language
2 special areas involved in language?
Broca’s area - motor/ability to talk (base of the left frontal lobe)
Wernicke’s Area - comprehends language (posterior temporal lobe)
Limbis System
In the cerebral hemispheres
Collection of structures
Responsible for emotional reactions and feelings
Diencephalon
contains the thalamus and hypothalamus
Thalamus
its a sorting and relay station for incoming sensory impulses
Hypothalamus
maintains homeostasis (body temp, intake of food & fluid and regulation of sleep cycles)
regulate libido
What’s in the brain stem
Pons
Medulla Oblongata
Reticular Activating System (RAS)
Pons
contains afferent (incoming) and efferent (outgoing) fibers
Medulla Oblongata
regulate resp and cardio function
RAS
decides which of the incoming sensory impulses the brain ignores or notices
Cerebellum
coordinate movement and maintain posture and equilibrium
How does blood get to the brain
By the internal carotid and vertebral arteries
- Once blood is oxygenated, venous blood from the brain collects in the dural sinuses and then drains into the jugular veins to be returned to the heart
Circle of Willis
Supplies blood to the brain
ensures blood flow remains unimpeded in case of any of the principal supplies are damaged
What’s part of the Circle of Willis
Middle cerebral
Ophthalmic
Internal Carotid
Basilar
Vertebral
Anterior communicating
Anterior Cerebral
Posterior Communication
Posterior cerebral
What are the 12 Cranial Nerves
Olfactory
Optic
Oculomotor
Trochlear
Trigeminal
Abducens
Facial
Vestibulocochlear
Glossopharyngeal
Vagus
Spinal Accessory
Hypoglossal
Olfactory
Smell
Sensory nerve
Optic
Vision
Sensory nerve
Oculomotor
Eye movement (including eyelids)
Motor nerve
Tochlear
Eye movement
Motor nerve
Trigeminal
General Sensory (eye, nose, face or oral cavity, teeth)
Speech muscles
Both (sensory and motor)
Abducens
Eye movement
Motor nerve
Facial
Taste, muscles of facial expression, scalp muscles
Both (sensory and motor)
Vestibulocochlear
Hearing and balance
Sensory nerve
Glossopharyngeal
Taste, gag reflex
Both (sensory and motor)
Vagus
external ear, parts of taste, heart and lungs smooth muscles, glands of GI system, Diaphragm
Both (sensory and motor)
Spinal Accessory
voluntary muscles of pharynx
head movement
Motor nerves
Hypoglossal
muscles of the tongue
Motor nerve
Spinal Cord
Starts at the medulla oblongata and ends at the 1st lumbar vertebra
nerves that innervate the skeletal muscles
Cauda equina
bundle of nerve root past 1st lumbar
what does the ascending tracts do?
relay information from the skeletal to the brain
what does the descending tracts do?
movement
goes from brain to the muscles
(Look at photo on slide 36 of week 11)
Spine breakdown
Cervical - C1-7
Thoracic T1-12
Lumbar L1-5
Sacral - S1-5
Coccyx - 4
Dermatones
innervate at the skin level
can be mapped on body to determine where damage occurred to the spinal cord
(Look at slide 39 to week 11 for map)
how may pairs of spinal nerves are there?
What do they do?
31 located in the spinal column
they carry motor and sensory fibres to and from the organs and tissues
Reflexes
automatic, rapid, involuntary responses to a stimulus
Neurons
cells that conduct impulses throughout the CNS and PNS
requires glucose and O2 for metabolism
What are the part of a neuron
Dendrite
Cell body
Axon
Myelin Sheath
Nodes of Ranvier
Dendrites
conducts the impulse towards the body
Axon
impulses away from the cell body towards the effector sit or connecting neuron
myelin sheath
insulates fibers
speeds up the rate of condition
Impulse Transmission *
Impulses are transmitted from cell to cell via chemical neurotransmitters
Involves presynaptic and postsynaptic synapses
For impulses to travel along, the released chemical flows across the cleft to the receiving receptor
Different chemicals do different things
(look at slide 44 week 11)
Types of chemical neurotransmitters *
Acetylcholine
Norepi/Epinephrine
Dopamine
Serotonin
Acetylcholine
chief neruotransmitter in PNS
Norepi/Epinephrine
neurotransmitter in SNS
Causes vasoconstriction and increases HR
Dopamine
cycle of motivation, reward and reinforcement
releases when body is expecting reward
Serotonin
mood, sexual desire and function, appetite, sleep, memory and learning, temp regulation and social behavior
SNS
fight or flight
stress
increases level of activity (cardio, resp and neurologic functions)
release of Ach , Epi and norepi
PNS
slows RR, HR
constricts pupils
dominates digestive system
Aids in recovery after sympathetic stimulation
innervated by vagus nerve
active chemical neurotransmitters is Ach
