unit 1 week 4

nervous system function

sensory input, integration, motor output

nervous system cells

neuron, neuroglia

irritability

ability to respond to a stimulus

conductivity

ability to transmit an impulse

schwann cell

forms myelin in PNS

oligodendrocyte

forms myelin in CNS

nodes of ranvier

gaps in myelin, enables fast jumping conduction

endoneurium

warps around one axon

perineurium

wraps a fascicle

fascicle

bundle of nerves

epineurium

wraps around whole nerve

multipolar neuron

many dendrites, most common

bipolar neuron

one dendrite, one axon, special senses

unipolar neuron

single process that splits, sensory neuron

astrocyte

supports neurons, repair, transfer nutrients

microglia

phagocyte of CNS

oligodendrocyte

produce cns myelin

CNS

brain + spinal cord

PNS

nerves outside of CNS

Motor pathway

efferent, carries impulse from CNS

sensory pathway

afferent, carries impulses to CNS

autonomic nervous system

not conscious control

parasympathetic

rest and digest, Craniosacral

sympathetic

fight or flight, thoracolumbar

cerical enlargement/lumbar enlargement

enlarged region in spinal cord for limbs

dorsal root

sensory fibers enter spinal cord

dorsal root ganglion

sensory neuron cell bodies

ventral horn

motor neuron cell bodies

ventral root

motor fibers exit spinal cord

gray matter

cell bodies

white fibers

axons

ascending tracts

sensory pathway to brain

descending tracts

motor pathways from brain

meninges

protective coverings of CNS

dura mater

tough outer layer

periosteal layer

outer dura layer attaches to skull

meningeal layer

inner dura layer covering brain

falx cerebri

dura fold between cerebral hemisphere attaches to crista gali

subdural space

between dura and arachnoid

subdural hematoma

bleeding into subdural space

arachnoid mater

web like middle layer

subarachnoid space

filled with CSF and major vessels

cerebrospinal fluid

cushioning fluid for CNS, makes brain lighter

pia mater

delicate layer tightly on brain surface

forebrain

Cerebrum

Hypothalamus

Mammillary Bodies

Pituitary Gland

Thalamus

Epithalamus

cerebrum

conscious thought, sensation, voluntary movement

basal ganglia

movement regulation, intensity

thalamus

relay station to cerebral cortex

hypothalamus

ANS, temp, hunger

mammillary bodies

memory, olfactory related

pituitary gland

endocrine master gland

epithalamus

basically the pineal gland

pineal gland

secretes melatonin

midbrain

cerebral peduncles, superior colliculi, inferior colliculi

cerebral peduncles

motor tract connecting cerebrum to spinal cord

superior colliculi

visual reflex centers

inferior colliculi

auditory relay

hindbrain

cerebellum, pons, medulla oblongata

brainstem

midbrain + pons + medulla

brainstem function

automatic survival behaviors

reticular formation

maintains alertness

medulla olives

sensory relay

longitudinal fissure

separates left/right hemispheres

transverse fissure

separates cerebrum from cerebellum

sulcus

shallow groove

fissure

deep groove

gyri

bumps

central sulcus

divides frontal and parietal lobes

lateral sulcus

separates temporal from frontal/parietal

parietal occipital sulcus

separates parietal occipital

precentral gyrus

primary motor cortex

postcentral gyrus

primary sensory cortex

frontal lobe

executive control, personality

parietal lobe

sensory processing, spatial awareness

occipital lobe

vision

temporal lobe

hearing, memory, language

cerebral cortex

conscious processing

prefrontal cortex

reasoning, memory, emotions

primary motor cortex

controls skeletal muscle

broca’s area

motor speech production

homunculus

body map representation in cortex

internal capsule

Communication between cerebral areas and lower CNS centers

corpus callosum

connects left and right hemispheres

ventricle

CSF filled brain cavity

ventricle order

lateral ventricle, interventricular foramen, third ventricle, cerebral aqueduct, fourth ventricle, central canal

septum pellucidum

thin membrane between lateral ventricles

circle of willis

arterial ring supplying brain

anterior cerebral artery

medial frontal/parietal supply

middle cerebral artery

lateral frontal parietal temporal supply

posterior cerebral artery

Occipital + inferior temporal supply.

CVA

cerebral vascular accident, blockage or hemorrhage affecting blood flow

dural sinuses

venous channels draining to internal jugular veins

alzheimer’s disease

degeneration of gray matter, memory loss

parkinson’s disease

movement initiation/termination difficulty

huntington’s disease

excessive movement, chorea