neuroanatomy - unit 1

parts of nervous system

brain, spinal cord, ganglia, nerves

central nervous system structures

brain and spinal cord

peripheral nervous system structures

peripheral ganglia and nerves (cranial and spinal)

afferent division of nervous system

somatic sensory (body), visceral sensory (organs, stomach), special sensory (senses outside of touch)

efferent division of nervous system

somatic motor (voluntary movements), autonomic motor (involuntary movement)

neurons

info processing and signaling within and between cellsn

neuroglia/glia

supportive functions to neurons

parts of a neuron

soma/cell body, dendrites, axon, axon terminals, synapse

soma/cell body function

receives and integrates info, initiates response, site of protein synthesis

dendrites function

branches extending from soma, receive incoming info from neighboring neurons and initiate an action potential to travel down length of axon

axon function

transmit electrical and chemical signals away from neuron’s cell body to other neurons, muscles, or glands. MYELIN COATING FOR FASTER TRANSMISSION

synapse

gap between neurons

synapse that occurs between axons and dendrites

axodendritic

synapse that occurs between axons and axons

axo-axonic

synapse that occurs between axons and somata

axosomatic

sensory afferent neurons

detect internal and external sensory stimuli

interneurons

integrates info and decides how to respond, between sensory and motor, communicate with motor efferent nerves

motor efferent neurons

sends motor commands to respond to stimuli

multipolar neuron (motor) types

pyramidal cells, interneurons

bipolar neuron (sensory) types

peripheral ganglia, retina

pseudounipolar neuron (sensory) types

dorsal root ganglia

action potentials

electrical signaling within cells

neurotransmission

chemical signaling between cells

grey matter

cell bodies and dendrites

white matter

myelinated bundles of axons

astrocytes

maintain integrity of blood brain barrier and protect brain tissue, modulate neuronal microenvironment (take away waste and provide nutrients)

microglia

become active during immune response and try to correct threat to brain tissue

ependymal cells

line ventricles and are ciliated, help move CSF through ventricular system

oligodendrocytes

provide myelination for neurons, extend multiple processes and wrap large regions of multiple neurons

types of glial cells in CNS

astrocytes, microglia, ependymal cells, oligodendrocytes

types of glial cells in PNS

schwann cells, satellite cellss

schwann cells

promotes regeneration

satellite cells

provide support and modulate neuronal microenvironment

major regions of CNS

cerebrum, diencephalon, brainstem, cerebellum, spinal cord

cerebrum structures

2 hemispheres, cerebral cortex

diencephalon structures (broad)

thalamus and hypothalamus

brainstem structures

midbrain, pons, medulla oblongata

cerebellum structures

2 hemispheres

cerebral cortex cortical lobes

frontal, parietal, temporal, occipital, brainstem, cerebellum

cerebral cortex landmarks

longitudinal fissure, central sulcus, lateral (sylvian) fissure, parieto-occipital sulcus, cingulate sulcus

longitudinal fissure location

between 2 hemispheres

central sulcus location

frontal from parietal

lateral (sylvian) fissure location

temporal from parietal and occipital

parieto-occipital sulcus location

between parietal and occipital

cingulate sulcus location

above singulate gyrus

brainstem function

maintain homeostatis

midbrain function

eye movements, auditory and visual reflexes

pons function

tracts, axon highway

medulla function

vital autonomic functions (breathing, heart rate, blood pressure)

cerebellum function

coordination, balance, motor learning

gray matter shape in spinal cord

H-shape

spinal segments

cervical, thoracic, lumbar, sacral

number of cranial nerve pairs

12

number of spinal nerve pairs

31

cervical spinal nerves

c1-c8

thoracic spinal nerves

t1-t12

lumbar spinal nerves

l1-l5

sacral spinal nerves

s1-s5

coccygeal spinal nerve

coc 1

neuraxis

axis of CNS

meninges

connective tissue found in brain and spinal cord

layers of meninges (outermost to inner)

dura mater, arachnoid mater, pia mater

direction of csf flow in spinal cord

down spinal cord

direction of white matter and gray matter flow in spinal cord

flows up spinal cord

spinal nerves with most gray matter

cervical (c1-c8) and lumbar (l1-l5)

where spinal cord ends

around l1-l2

cauda equina location

bundle of spinal nerves from L2-coccygeal nerve

gray matter structures in spinal cord

dorsal horn, ventral horn, lateral horn

white matter structures in spinal cord

dorsal column, lateral column, ventral column, anterior white commissure

dorsal horn

sensory received from periphery

ventral horn

voluntary and reflexive motor

lateral horn

local interneurons connect sensory and motor

dorsal column

posterior axon bundle (sensory)

lateral column

lateral axon bundle (voluntary and reflexive motor)

ventral column

axons connecting right and left sides

anterior white commissure

small axon body connecting two homolagous regions

dorsal roots

axons of sensory (afferent) nerves

dorsal root ganglion

cell bodies

ventral roots

contains axons of motor (efferent) nerves

roots that convey signals toward spinal cord

dorsal root ganglion

roots that convey signals away from spinal cord

ventral roots

mixed spinal nerve

created by ventral and dorsal roots, carries motor and sensory info

coronal cut

anterior and posterior

saggital cut

left and right

horizontal cut

dorsal and ventral

central sulcus

separates frontal and parietal lobes

lateral fissure

separates frontal, temporal, and parietal lobes

longitudinal fissure

separates two hemispheres

parieto-occipital sulcus

separates parietal and occipital lobes

prefrontal cortex

personality and behavioral regulation, executive function, movement, language production, behavior and personality, memory, beginning of motor pathway for voluntary movement

frontal lobe motor areas

primary motor cortex: precentral gyrus, execution of voluntary movements for entire body

lobe where Broca’s area resides

frontal lobe

parietal lobe

spatial relationships for physical world and imagination, cross-modal integration, phonological and articulatory processing of words

regions of parietal lobe

primary somatosensory cortex: postcentral gyrus, somatosensory association cortex, inferior parietal lobule (supramarginal and angular gyri), superior parietal lobule, primary vestibular cortices

injuries in parietal lobe

alexia, agraphia, acalculia, apraxia, agnosia

temporal lobe

auditory processing, language comprehension, speech production, learning and memory, emotion, behavior

temporal lobe structures

primary auditory cortex: heschl’s gyrus on superior temporal gyrus, language association area, wernicke’s area, primary olfactory cortex, hippocampus and amygdala

injuries in temporal lobe

wernicke’s aphasia, memory disturbances, epilepsy, inability to recognize patterns

occipital lobe

vision and color perception

occipital lobe structures

primary visual cortex (along calcarine sulcus), visual association areas (secondary and associative visual cortices)