Neurology - basics Flashcards
What is the morphological classification of the NS?
CNS - brain and spinal cord
PNS - everything else incl cranial and spinal nerves
Direction of flow classification?
Afferent/sensory system - information toward from CNS/PNS
Efferent/motor system - information away from CNS/PNS
Physiological classification?
Somatic/voluntary - coordinates voluntary control
Visceral/involuntary - involuntary activities such as digestion
What is grey and white matter?
Grey matter - cell bodies
White matter - axons
What is the blood supply to the brain?
Via the carotis arteries, which pools in cerebral arterial circle before distributed to the brian.
Brain requires rich blood supply.
What is the ventricular system of the brain?
A system of cavities through the brain, which contain ependymal cells. These secrete cerebrospinal fluid from the choroid plexus.
What is cerebrospinal fluid?
Its ultra-filtrated blood, containing glucose and minerals for nutrition and provides shock support.
What are the layers that protect the brain?
Skull bone
-Epidural space
-Dura mater
-Subdural space
-Arachnoid layer
-Subarachnoid space
-Pia mater
What is the epidural space?
Loose connective tissues, veins and lymphatics. This cusions the brain.
What is the dura mater?
Thick, dense fibrous tissue fused with bone
What is the subdural space?
Contains lubricating fluid
What is the arachnoid layer?
Has cerebrospinal fluid and blood vessels providing nutrition and cushioning
What is the subarachnoid space?
Cerebrospinal fluid leaking from the ventricular system with varying thickness
What is the pia mater?
A thin layer on the brain with many tiny blood vessels.
What are the elevations and depressions called?
Folds - gyri
Grooves - sulci
What is the peripheral NS?
links the environment with the central nervous system using efferent and afferent fibres.
All spinal nerves are a mix of sensory and motor.
What are cranial nerves?
Sensory
I - olfactory
II - optic
VIII - vestibulocochlear
Motor
III - oculomotor
IV - trochlear
VI - abducten
XI - accessory
XII - hypoglossal
Mixed
V - trigeminal
VII - facial
IX - glossopharyngeal
X - vagus
What is the anatomy of the neurones?
Cell body/soma - converts signal to membrane potential, contains nucleus
Dendrites/receptor segment - conducts impulse and recieves information
Axon/neurone fibre - relays impulses to other neurones and effector organs. Myelinated for insulation by Schwann cells in PNS and Oligodendrocytes in CNS
What are the protein molecules on the nerve membrane?
Receptor proteins - bind to neurotransmitters
Channel proteins - acts as pores for ion movements
Transport proteins - transfer ions
What are the different classifications of neurones?
Multipolar - most common. Multiple dendrites and one axon e.g. motor neurones
Bipolar - one dendrite and one axon e.g. olfactory, retina and ear. Cell body in middle.
Pseudopolar - sensory information from skin and organs to spinal cord e.g. sensory neurones
What makes up the support matrix?
Neuroglia surrounds neurones and supports it all. Capable of mitotic activity.
Fibrillary and protoplasmic astrocytes - nourishment and metabolic support
Oligodendrocytes - insulate the cells of CNS
Microglia - macrophages of the CNS and 10-15% of the brain cells