Neuro Flashcards
Where does the DCML tract decussate?
Medulla
Which tract carries crude touch and pressure?
Anterior spinothalamic
Which tract carries pain and temp?
Lateral spinothalamic
Where do the spinothalamic tracts cross?
Spinal cord (climb 1/2 levels first)
What are the pyramidal tracts?
- originate in the cerebral cortex
- voluntary control
What are the extrapyramidal tracts?
- originate in the brain stem
- involuntary control
Where does the corticospinal tract receive inputs from?
- primary motor cortex
- pre motor cortex
- supplementary motor area
- somatosensory area(ascending tract)
Which tract carries fine touch, vibration and proprioception?
DCML
Where do the corticospinal tracts terminate?
Ventral horn
What are the myelin forming cells called in the brain and spinal cord?
Oligodendrocytes
What are the myelin forming cells called in the peripheral nervous system?
Schwann cells
What is the neurotransmitter for UMN?
Glutamate
Where are LMN located?
- Ventral horn and anterior nerve roots
- Cranial nerve nuclei of brainstem
What type of neurones innervate extrafusal muscle fibres?
Alpha motor neurones
What type of neurones innervate intrafusal muscle fibres?
Gamma neurones
What do LMN use at the neuromuscular junction?
ACH
Which lobe is Broca’s area in?
frontal
Which lobe is Wernicke’s area in?
Temporal
What separates the cerebellum from the occipital lobe?
Transverse fissure and tentorium cerebelli
What is the function of the cerebellum?
- voluntary motor movement
- balance
- muscle tone
What is the cerebellum lined with above and below?
Non nervous tissue called medullary velum
How does the cerebellum communicate with the subarachnoid space?
- median aperture
- 2 lateral apertures
How many layers does the cortex have? What are they?
3 layers 1) molecular-synapse with purkinje fibres 2) purkinje 3) granule (White matter beneath these 3 layers)
How many inputs does the cerebellum have?
2
- mossy fibres (middle peduncle)
- climbing fibres (inferior peduncle)
How many outputs does the cerebellum have?
1
-purkinje cell axons
Name 3 functions of CSF
Protection
Buoyancy
Chemical stability
Where is CSF produced?
Ependymal cells in the Choroid plexus
What is the ventricular system derived from?
Lumen of the neural tube
How are the lateral ventricles connected to the third ventricle?
Foremen of Monro
How does CSF flow to the 4th ventricle?
Cerebral aqueduct
How does the 4th ventricle communicate with the subarachnoid space?
Foramen of Magende and Foramina of Luschka
What are the functions of the blood brain barrier?
1) maintain constant intracerebral chemical environment
2) control entry of cells and molecules
3) protect against osmotic change
Brown sequard syndrome
- ipsilateral loss of touch and proprioception(same level)
- ipsilateral pyramidal weakness
- contra lateral loss of pain and temp (few segments below the lesion)
What forms the straight sinus?
Inferior Sagittal sinus + great cerebral vein
Where does the superior cerebral vein drain into?
Superior Sagittal sinus
Where does the inferior sagittal sinus receive blood from?
Cerebral veins from the medial surface of the cerebral hemisphere
Where does the transverse lie? And drain into?
- lies in the posterior fixed margin of the tentorium
- drains into sigmoid sinus then internaljugular vein
What is pain?
An unpleasant and emotional experience associated with actual or potential tissue damage
Where are nociceptors?
The cell body is in the dorsal root ganglion or trigeminal ganglion
What are the neurotransmitters of nociceptors?
Glutamate and substance p
How does substance p work?
-binds to neurokinin-1 receptors
What is neuropathic pain?
Pain arising as a direct consequence of a lesion or a disease of the somato-sensory system
Where does the periaqueductal grey receive input from?
Cortical and subcortical areas
Why is substantia nigra black?
Dopaminergic cell bodies are located here
