1

back side

front side

inner layer

outer layer


### Matters

= brain regions

brain is made up predomenatly form gray coloured matter

gets its colour form capillaries and neuronal cell bodies

= the pathways, connections between brain areas

consistts of axons and connections between them

axons are myelinated ( insulated ) by oligocides and Schuwann cells

made out of fatty lipid → white milky appereance

crucial for signal transmission from one area to another brain area

most myelin is situated subcortical

white matter and gray matter have distinct aspects in cortical vs subcortical regions

tracts and pathways are white matter but not all of them

these are also unmyelinated pathways

(for example those that are transmitting painful stimuli)

the spinal cord lies inside the bony spinal column

five anatomical regions from top to tail make up the spinal cord

31 corresponding spinal cord segments within the 5 regions

outer cord consists of white matter tracts

the interioir cord consists of gray matter ( cell bodies in shape of butterfly)

in general the **posteror** part of each spinal segment is **sensory** and **anterioir is motor**

afferent fibers enter posterioir spinal cord to brin ginformation in from the body's senosry receptors (posterir root)

efferent fibers exit the anterioir spinal cord to carry information form spinal cord out to the muscles (anterioir root)

1. sypathetic
2. parasympathetic

arouses the body for action

stimulates heart to beat faster

inhibits digestion

fight or flight

slows down the body

blows down hearbeat

stimulates digestion

associated with rest and digest

Arteries and blood supply

1. ACA
2. MCA
3. PCA

anterioir cerebral artery (ACA) : irrigates dorsal andmedial parts

middle cerebral artery (MCA) :irrigates latteral surface of coretx

posterioir cerebral artery (PCA) : irrigates ventral and posterioir surfaces

arm/hand/face are innervated by brain regions that are located within the area of the middle cerebral artery

leg area receives blood supply from the anterior cerebral artery

70 % stroke patients have it in the middle cerebral artery

this causes severe cliniacal consequnces


### Fissure , Sulci and Gyri

**neocortex** : crinckled tissure consisting of clefts and ridges

cleft it extends deeply enough into the brain to indent ventricles

if it is shalower

if its a ridge