19.1 NS: General structure of the NS Flashcards
What does a diffusion weighted MRI of the brain show?
White matter tracts
Where does the brain have a major kink?
Between the midbrain and diencephalon
What are the ridges and grooves of the cerebrum called?
Gyri and sulci
Name the 4 lobes of the cerebral cortex
Frontal, parietal, occipital, temporal
What does the cerebellum do? How many neurons does it contain?
Refines execution of motor function
Half of all neurons in brain
What part of the brain are the basal ganglia in?
What is it important for?
Telencephalon
Selection and initiation of voluntary movement
What are the components of the basal ganglia?
Caudate
Putamen
Globus pallidus
(Subthalamic nucleus, substantia nigra, caudate + putamen=striatum)
What part of the brain is the thalamus in?
What does it do?
Part of dencephalon
Major sensory relay to the cortex
What are the 3 ways the thalamic nuclei project in?
Relay sensory info to specific cortical areas
Relay non sensory info from cortex/BG to specific cortical areas
Global projection to cortex for arousal/sleep
What 2 major roles does the hypothalamus have?
Regulation of homeostasis and control of pituitary
What does the brainstem control? (4)
Facial muscles
Face/head sensation
Cardioresp
Arousal/sleep-wake cycle
Where in the brain does the spinal cord connect to?
The medulla
What is the composition of the spinal cord?
Core of grey matter surrounded by white matter
Where is the spinal cord enlarged?
Where does it end?
At lower cervical and lumbar region (for limbs)
L1/L2
What types of axons are dorsal and ventral roots for?
Dorsal:sensory
Ventral: ventral horn motor axons
What does the dorsal root contain and what does this form?
Contains neuronal somata forming a dorsal root ganglion
Where do the branches of the DRG neurons go?
One in peripheral nerve (stimuli detection)
One enters dorsal horn via dorsal root
What is the definition of a dermatome?
The region of the body innervated by a bilateral pair of DRG
What makes CSF? Where does it flow out? What space does it fill? Where does it get reabsorbed?
Choroid plexus makes CSF, flows out at fourth ventricle
Fills subarachnoid space, reabsorbed by veins at arachnoid granulations
What divides the cerebral hemispheres? What separates the cerebellum from the occipital lobe?
Falx divides
Tentorium separates C from OL
What is the BBB formed by?
What type of transport is needed to get through BBB?
Tight junctions of endothelial cells (of capillaries)
Active transport
