Neuro Physiology Flashcards
Divisions of PNS
Somatic and autonomic
4 divisions of spinal cord superior to inferior
Cervical
Thoracic
Lumbar
Sacral
Dorsal root stimulation
Sensory
Ventral root stimulation
Motor
What is the forebrain divided into
Telecephalon
Decephalon
Term for midbrain
Mesencephalon
Hindbrain division and what they include
Myelencephalon - medulla and pond
Purpose of thalamus
Relay structure
Specific nuclei
Purpose of hypothalamus
Homeostatis
Pleasure and sexual behavior
Hormonal control
Advantgea of ct over mri
Ct scan is quicker
Better to demonstrate bone calcification
Advantages of mri
No ionising radiation
Multiple planes possible
Excellent anatomical detail
Disadvantages of mri
Longer scan times
Noisy and claustrophobic
Strong magnwtic field
what do the extra ocular muscles do and where are they
muscles that control the movement of the eye
inside the orbit
4 elements of the blood brain barrier
Endothelial cell tight junctions
Lack of bm fenestrations
Astrocytic end feet
Pericytes
Purpose of lack of basement membrane fenestratiosn
Acts as a barrier
Purpose of astrocytic end feet
They regulate the permeability of the blood brain barrier
difference between CNS and PNS
CNA- Brain and spinal cord , collection of cell bodies in the CNS
PNS- nervous system outside the CNS
which nerves have parasympathetic fibers
oculomotor
faciAL
VAGUS
GLOSSOPHARANYGEAL
what is a nuclei
a collection of cell bodies within a nerve cell
role of olfactory nerve
sensory- smell
receptors in nasal cavity
axon bundles travel through cribriform plate
role of optic nerve
sensory nerve
fibres travel from the retina
nerve passes through optic canal
primary visual cortex
where do the LMN and UMN start
umn- higher centres and project down to meet Lmn
LMN- begin in brainstem or spinal cord and projects to the muscle
define motor unit
single alpha motor neuron and all the muscle fibers it innervates
define motor pool
all lmn that innervate single muscle
What is bottom up processing
Involved with sensation
What is a motor neuron
Carries information from brain or spinal cord and is involved in the regulation of activity in muscles
Function , modality and foramens of olfactory nerve cn1
Sensory and smell
Leaves via cribriform plate in the ethmoid bone
Function, modailty and foramen of optic and occulomotor nerve
Optic - sensory and vision, optic canal
Occulomotor - motor and 4 extrinsic eye muscles, levator palpebrae and pupillary sphincter, superior orbital fissure
Function , modality and foramen of trochlear nerve cn4
Superior oblique and motor
Superior orbital fissure
Function , modality and branches of trigeminal nerve
Opthalmic - scalp forehead and nose
Maxillary - cheeks., lower eyelid, upperlip
Mandible - anterior 2/3 of tongue
Sensory and motor
Function modality of cn 6-8
6- abducens, lateral rectus , motor
7- facial , muscles of facial expression BOTH
8- vestibulocochlear hearing and balance SENSORY
Function and modality of cn 9 and foramen
9- glossopharyngeal ,
Sensory , tonsils , carotid sinus , middle ear
Motor , stylopharangeus
Parasympathetic parotid gland
originates in medulla and LEAVES VIA THE JUGULAR FORAMEN
Is thr cortico brainstem spinal tract indirect or direct
Indirect
Compare dorsolateral and ventromerial tract
Both havw direct corticospinal and indirect via brainstem nuclei
Dorsal innervate contrlaterally
Dorsal projects to distal muscles
Ventro to proximal muscles
What is the basal ganglia
Group of nuclei that are deep within cerebral hemispheres
compare autonomic and somatic system
Somatic is volountary
Autonomic is conscious
S- fibres do not synapse after they leave the cns
A- fibres synapse at a ganglion after they leave the cns
S - innervates skeletal muscle
A- innervates smooth muscle cardiac cycle muscle
function of ANS
Thermoregulation, exercise, digestion, competition, sexual function
sympathetic functions of ANS
increase heart rate and force of contraction
vasoconstriction
bronchodilation
decrease motility
parasympathetic functions of ANS
decrease heart rate and force of contraction
no effect on blood vessels
bronchoconstriction
what innervates the upper thorax
greater splanchic nerve
cranial nerves that are parasympathetic
oculomotor
facial
glossopharyngeal
vagus
neurotransmitter in the enteric system
5HT
noradrenaline receptor types?
alpha 1 and 2
beta 1 2 3
two subgroups of basal ganglia
striatum and globus pallidus
basics of parkinsions
increased muscle tone
reduced movement
not enough dopamine
basics of huntingtons
decreased muscle tone
overshooting movements
too much dopamine
synthesis of dopamine
synthesised by l- tyrosine with the enyzme tyrosine hydroloxase
l - DOPA with DOPA decarboxylase to dopamine
dopamine receptors and how many
d1 d2 d3 d4 d5
5
function of basal ganglia
fine tuning of movements
features of UMN damage
Spasticity
spastic weakness
brisk reflexes
positive babinski reflex
common causes of UMN damage
brain stem - strokes, tumours , demyelination
spinal cord- MS, cord compression, spinal cord , vit b12 deficiency
features of lower motor neurone damage
weakness- flaccid
reduced tone
muscle wasting
absent deep tendon reflexes
Pathway of right vagus nerve
Anterior (infront) of subclavian artery and posterior to the sternoclavicular joint
Pathway of left vagus
Inferiorly between left common corotid and left subclavian arteries , posterior to the sternoclavicular joint
Function of trigeminal nucleus
Receives sensory info from the face
Function of nucleus ambigus
Motor nucleus for muscles of pharynx and larynx
Where is the ethmoid bone located
Roof to the nasal cavity
Helps to separate nasal cavity from cranial cavity
What makes up the ethmoid bone
Cribriform plate
Perpendicular plate
Ethmoidal Labyrinth
Foramen of branches of trigeminal
Ophthalmic , superior orbital fissure
Maxillary foramen rotundum
Mandible - Foramen ovale
What does the mandibular nerve innervate
Tensor tympani
Tensor veli palatini
Anterior 2/3 of tongue
Facial nerve functions
Motor , facial expression in face
Sensory. Mouth and external ear
Special sensory , taste , anterior 2/3 on tongue
Parasympathetic , mucous glands , lacrimal glands , salivary glands excluding parotid .
Foramen of facial nerve
Leaves cranial vault via internal acoustic meatus and into face through stylo mastoid foramen
Foramen of vestibulocochclear nerve
Exits inner skull via internal acoustic meatus in the temporal bone
Function modality and foramen on cn X
Vagus Both
Sensory , lungs , trachea and digestive tract
Motor, laryngeal , pharanygeal neck muscles
Parasympathetic , every organ above level of the colon except adrenal gland
Leaves via the jugular foramen
Function modality and Forman of cn xi
Accessory
Motor
Innervates trapezius and STM
jugular foramen
Function modality and foramen of cn12
Hypoglossal
Motor
Innervates intrinsic and extrinsic muscles Of the tongue
Foramen magnum
6 bones of cranium
Frontal Ethmoidal Sphenoid Parietal Occipital Temporal
Structures that pass through superior orbital fissure
Cn3,4,6 and ophthalmic
Structures that pass through internal acoustic meatus
Facial n
Vestibulochcochlear n
Structures that pass through jugular foramen
Cn 9,10,11
What is a ganglion
A collection of cell bodies
Primary function of blood brain barrier
Providing selective nutrient passage
Controlling fluid movement
Protecting from toxins
How can permeability of blood brain barrier change
Inflammation
Permeant molecules
Impermeable molecules
Difference between alpha and gamma motor unit
Alpha , muscle contraction in voluntary movement
Gamma muscle contraction in response to external forces acting on the muscle
What muscle fibres attaches to tendons
Extrafusal fibres
What innervates Golgi tendon organ
Type 1 b fibres
Sensory fibres
What do tendons connect To
Bone
What are Golgi tendon organs a type of
Proprioceptors
What does GTO detect
Tension from muscle contraction
Type 1a stretch response
Synapse with and excite alpha motor neurone from the same muscle and cause contraction to help shorten it
Inverse stretch reflex
Inhibition of contracting muscle
Stimulation of agonist muscle
Type 2 stretch reflex
Synapse with and inhibit alpha motor neurones of the antagonistic muscle causing relaxation
Patellar reflex
Patella knocked Activates stretch receptors in knee 1a fibres from intrafusal fibres Synapse with motor neurone Cause immediate contraction of quadriceps
3 examples of fast neurotransmitters
Ach both excite and inhibit
GABA inhibitory
GLUT mainly excite
How is neuron resting potential maintained
3na+ are pumped out the cell for every. 2k+ in
Use of atp and na/k transport pumps
What provides insulation to axons in CNS
Oligodendrocytes
What produces a myelin sheath around neuronal axons in the PNS
Schwann cell
What does Saltatory conduction allow for
Myelin sheath insulated membrane
Conduction between nodes of ranvier
Faster conduction
Function of myelin
Made from glial cells
Insulates the axon
Stop it from decaying due to electrical current leaking through axonal membrane
5 steps in synaptic transmission
Manufacture Storage Release Interact with post synaptic receptors Inactivation
What can damage to myelin sheath cause
MS-scar tissue on myelin
Guillian barre syndrome -damage to pns myelin
Is a neuromuscular junction excitatory or inhibitory
Excitatory
What is spatial summation
Several presynaptic neurones release neurotransmitter to 1 post synaptic cleft
What is temporal summation
High frequency of action potentials in pre synaptic neuron
Slow neurotransmitter examples
Serotonin
Noradrenaline
What is a modulators neurotransmitter
Capable of affecting a larger number of neurons at the same time
Difference between somatic efferent and autonomic efferent
Somatic , single myelinated axon
Only excitatory with ach
Autonomic, preganglionic and post ganglionic
Pre- ach
Post - ach or nad
Main difference in terms of axons between sympathetic and parasympathetic ns
Symp- short preganglionc axon
Para- long preganglionic axon
