CNS IA and IB Flashcards
gives rise to the skin and the
nervous system
ectoderm
Brain and spinal cord arise from here
neural tube
develops into the brain
rostral
develops into spinal cord
caudal
becomes the central canal of the spinal cord and
the ventricles of the brain
central cavity
closure by day 27
Superior Neuropore
closure after 3 days
Inferior Neuropore
form the sensory ganglia of
spinal and cranial nerves and also the autonomic ganglia
NEURAL CRESTS
Concentric Layers what day
day 26
composing of cell bodies
to gray matter
Mantle Layer
comprising of axons >
white matter
Marginal Layer
Motor Function
Anterior Basal Plate
Sensory Function
Posterior Alar Plate
As development continues, a longitudinal groove appears on the inners surface of the lateral walls of the embryonic spinal cord and caudal part of the
brain
sulcus limitans
By about the the ____ week, three primary brain
vesicles can be identified the
fifth week
○ prosencephalon (forebrain)
○ mesencephalon (midbrain)
○ rhombencephalon (hindbrain)
By the _____ week, further differentiation
distinguishes five secondary brain vesicles
produced by
7th week
○ division of the prosencephalon into the telencephalon and diencephalon
○ division of the rhombencephalon into the metencephalon and myenchephalon
undergoes the greatest further development and
gives rise to the two cerebral hemispheres
telencephalon
contains numerous cell
groupings and is intimately connected with the
cerebral cortex
diencephalon
The brain and
skull are minute
and the infant
does not usually
survive
ANENCEPHALY
The lower spinal cord and
nerve roots are underdeveloped and may
lie uncovered by skin or
the bony spine on the
infant’s back
SPINA BIFIDA
Fluid in the spinal cord
SYRINGOMYELIA
outermost layer of dense fibrous
connective tissue
DURA MATER
Avascular Membrane between the dura
and pia mater
ARACHNOID MATER
Oldest lobe
INSULA (ISLAND OF REIL)
contain
neurotransmitter
substances to excite or inhibit
postsynaptic neuron
presynaptic vesicles
provide energy to synthesize
neurotransmitter
mitochondria
either opens an ion
channel or activates a second messenger
system
ionophore component
cation channels most often allow
Na
anion channels allow
Cl
About 75% of the SMAs are transduced with
G-protein coupled receptors
Neurotransmitter of PRESYNAPTIC INHIBITION
GABA
when multiple presynaptic neurons are excited simultaneously and their excitatory postsynaptic potentials (EPSPs) together exceed the threshold
SPATIAL SUMMATION
a single presynaptic neuron is stimulated repeatedly in quick succession
TEMPORAL SUMMATION
Effect of Acidosis
Decreases neuronal activity ; coma
Effect of Alkalosis
Increases neuronal excitability; seizures
Effect of Hypoxia (low oxygen)
can lead to unconsciousness
The muscle-type can be selectively
blocked by curare, the neuronal-type by
hexamethonium
Nicotinic (Ionotropic)
Excitatory or inhibitory Ach
Muscarinic (metabotropic)
most common form of
dementia; acetylcholine loss
Alzheimer’s Disease
Major excitatory neurotransmitter of the brain
and spinal cord
Glutamate
Disorder of Glutamate
epileptic seizures
main inhibitory neurotransmitter
GAMMA AMINOBUTYRIC ACID (GABA)
Disorder of GABA
Seizures
It is released from sympathetic nerves, the
adrenal medulla and brain stem neurons
NOREPINEPHRINE
Disorders of NE
● Depression
● Withdrawal from some drugs of abuse
● Anxiety and other stress-related disorders such
as panic disorder
Has a very wide-spread projection system
NORADRENERGIC SYSTEM
Dopamine disorder
schizophrenia
Third pathway, known as the tubero- infundibular
system
DOPAMINERGIC SYSTEM
Functions
○ Improved mood
○ Decreased appetite
○ Sleep
SEROTONIN
Disorders of Serotonin
○ Depression
○ Anxiety
Acetylcholine
Dopamine
Serotonin
Norepinephrine
Nucleus of Meynert
Substantia Nigra
Caudal Raphe
Locus Coeruleus
