EOM: NEURO Flashcards
What is responsible for venous drainage of the brain?
Sinuses formed between meningeal and periosteal dural layer
Note: cavernous sinus receives blood from the orbit
What is responsible for arterial supply of the brain?
- Left anterior cerebral artery –> motor cortex of right left
- Basal ganglia is supplied by lenticulo-striate arteries - branches of ACA/MCA
What is the middle cerebral artery a continuation of?
Internal carotid artery (directly)
Describe stroke syndromes and functional unites of the brain.
- Temporal stroke = memory
- Occipital stroke - contralateral homonymous hemianopia
- Stroke affecting internal capsule is usually haemorrhagic of lenticulostriate artery (from MCA - supply basal ganglia and posterior limb of internal capsule)
Where are muscles of the lower limbs and face represented?
- Lower limbs = medially
- Facial = laterally
Describe the course of the corticospinal tracts.
Pass between the basal ganglia and thalamus to enter the cerebral peduncle.
How do upper motor neurons innervate muscles?
Directly
What does the lateral corticospinal tract do?
Carries fibres controlling muscles involved in balance and posture
Where does the reticulospinal tract originate from?
Cells found in the pons and medulla - may act to facilitate or inhibit the activity of various ascending tracts.
What do gamma motor neurons innervate?
Extrafusal muscle fibres
What do muscle spindles detect?
Changes in muscle tension
Where are Golgi tendon organs located?
Smooth and cardiac muscle
What is the function of the Golgi tendon organs?
Activity results in the inhibition of the antagonist muscles in which they are found.
What is the relevance of receptive field sizes and behavioural specialisations of humans?
No relevance
What is the dorsal column-medial lemniscal system?
A tract which carries information regarding pain sensation from the skin to higher centres