ANATOMY LAB WEEK 9/10 NERVOUS SYSTEM

central nervous system

• brain and spinal cord

peripheral nervous system

• cranial nerves, spinal nerves, ganglia

sensory (afferent) division

• impulses sent to the brain through the nervous system

  • somatic _____

  • visceral _____

motor (efferent) division

• impulses sent from the brain to the motor muscles

  • somatic (____) nervous system

  • autonomic (visceral ____) nervous system

    • sympathetic nervous system

    • parasympathetic nervous system

somatic (motor) nervous system

• impulses sent to skeletal muscles

• voluntary

autonomic (visceral motor) nervous system

• impulses sent to smooth and cardiac muscles, glands

• involuntary

sympathetic nervous system

• activates the body in preparation for movement, response to stress

• fight or flight

parasympathetic nervous system

• relaxing the body, back to homeostasis

  • ex. digesting food and nutrients

• rest and digest

neurons

• communicates through nerve impulses/action potentials/electrical signals

synapse

• point of connection/junction between two neighboring cells

cell body (soma)

• has nucleus and organelles

dendrites

• receives messages/electrical signals

• branching from cell body

axon

• long tail of neuron

• action potential moves along it

axon terminals

• end of axon

• synaptic knobs/terminal boutons

myelin sheath

• coats axon with adipose tissue

• increases efficiency of sending message

• looks white

neuroglia (glial cells)

• helper neural tissue

gray matter

• neuron cell bodies, synapse, neuroglia

• cerebral cortex where processing occurs

  • NUCLEUS in CNS— region deeper in the brain

  • GANGLIA in PNS— bulges in nerves that house cell bodies

nucleus

• region of grey matter deeper in the brain

• grey matter in CNS

ganglia

• bulges in nerves that house cell bodies

• grey matter in PNS

white matter

• neuron myelinated axons, neuroglia

• fatty/adipose tissue

  • TRACTS in CNS— pathway, not own separate nerve structure, embedded in brain

  • NERVE in PNS— bunches together to create nerves

tracts (fiber tracts)

• pathway, not own separate nerve structure

• embedded in brain

• white matter in CNS

nerves

• neuron myelinated axons that bunch together

• white matter in PNS

  • axon+myelin sheath → fascicle+blood vessels → nerve

brainstem

• passageway (tracts) from higher brain (cerebrum) to rest of body via spinal cord

• automatic survival behaviors

  • medulla oblongata (inferior)

  • pons

  • midbrain (superior)

medulla oblongata

• pyramids

• olives

pyramids

• part of the medulla oblongata

• two longitudinal ridges

• carry voluntary motor outputs to spinal cord

• fiber tracts going up and down

olives

• part of the medulla oblongata

• large wavy fold of grey matter

• relay nucleus for sensory info from spinal cord lateral to pyramids

pons

• middle region of the brainstem

• bridge from brainstem to cerebellum

midbrain

• under thalamus

  • corpora quadrigemina

    • superior colliculli, inferior colliculli

  • cerebral peduncles

corpora quadrigemina

• midbrain

• 4 bumps on posterior brainstem, visual and auditory reflexes

cerebral peduncles

• little feet on anterior side of midbrain

cerebellum

• smooths and coordinates body movements

• helps maintain equilibrium

• “little brain”

left and right cerebellar hemispheres

• two hemispheres of cerebellum

vermis

• cerebellum

• fold down the middle

folia

• tight folds on external cerebellum

cerebellar cortex

• grey matter cortex of cerebellum

arbor vitae

• white matter of cerebellum, branching

diencephalon

• in between brain

  • thalamus

  • hypothalamus

  • epithalamus

thalamus

• 2 round lobes in the middle of the brain

• relays and processes information to the brain

  • interthalamic adhesion/intermediate mass

interthalamic adhesion (intermediate mass)

• connects left and right thalamus

hypothalamus

• control center of the body

• homeostasis and autonomic regulation

  • pituitary gland at end

pituitary gland

• master endocrine gland, synthesizes hormones to send out

• connects nervous system to endocrine system

• at the end of hypothalamus

epithalamus

• bridge between endocrine and limbic system

• behind thalamus

  • pineal gland

pineal gland

• secretes melatonin to maintain sleep wake cycle

• end of epithalamus

cerebrum

• upper part of the brain

  • lobes+insula

  • gyrus/gyri

  • sulcus/sulci

left and right cerebral hemispheres

• two halves of cerebrum

longitudinal fissure

• separates right and left cerebral hemispheres

central sulcus

• separates frontal lobe and parietal lobe

precentral gyrus

• just anterior to the central sulcus

• primary motor cortex

postcentral gyrus

• just posterior to the central sulcus

• primary somatosensory cortex

lateral sulcus

• separates the temporal lobe from the frontal and parietal lobes

transverse fissure

• separates cerebral hemispheres from cerebellum inferiorly

frontal lobe

• plan and initiate motor movement, eye movement and speech

• higher level cognition, thinking, planning, decision making, working memory

parietal lobe

• primary somatosensory cortex, processes sensory stimuli

• sensory stimuli, spatial awareness, written and spoken language

temporal lobe

• auditory and olfactory cortex

• recognition of words, faces, and objects

• language comprehension/production

• emotional response and memory

occipital lobe

• visual cortex

insula

• deep within lateral sulcus, makes up floor

cerebral cortex

• funtional areas

  • sensory areas

  • association areas

  • motor areas

sensory areas

• primary somatosensory cortex, primary visual cortex, primary auditory cortex, olfactory cortex

association areas

• prefrontal cortex

• (anterior frontal lobe)

motor areas

• primary motor cortex— movement

• broca’s area (left side of frontal lobe)— speak and make sound

corpus callosum (commissural fiber)

• white matter of the cerebrum

• crosses between left and right hemispheres

limbic system

• emotional response and memory

  • amygdala

  • hippocampus

  • thalamus

  • hypothalamus

ventricles

• continuous with the spinal cord

• produces and circulates cerebrospinal fluid

  • lateral ____

  • third ____

  • cerebral aqueduct

  • fourth ____

  • choroid plexus

lateral ventricles

• continuous with third ventricle

third ventricle

• ventricle in between two lobes of thalamus

cerebral aqueduct

• connects third and fourth ventricle

fourth ventricle

• connected to third ventricle

• between cerebellum and pons

• continuous with central canal of spinal cord

choroid plexus

• makes cerebrospinal fluid

meninges

• connective tissue coverings of the brain

  • dura mater

  • arachnoid mater

  • subarachnoid space

  • pia mater

dura mater

• outermost connective tissue of meninges

• thickest covering

arachnoid mater

• middle layer connective tissue of meninges

• looks like cobwebs

subarachnoid space

• between arachnoid mater and pia mater filled with cerebrospinal fluid

pia mater

• innermost connective tissue of meninges

• follows contours of the brain

olfactory CN I

• cranial nerve

• long widens at bulbs, above nasal cavity

• function

  • sense of smell

• fiber type

  • sensory

optic CN II

• cranial nerve

• has chiasma where nerves cross

• function

  • vision

• fiber type

  • sensory

oculomotor CN III, trochlear CN IV, abducens CN VI

• cranial nerves

• function

  • eye movements

• fiber type

  • motor

trigeminal CN V

• cranial nerve

• function

  • face sensation, mastication

• fiber type

  • mixed

facial CN VII

• cranial nerve

• function

  • face sensation, facial muscle movement, lacrimal glands, some salivary glands

• fiber type

  • mixed

vestibulocochlear CN VIII

• cranial nerve

• function

  • hearing and equilibrium

• fiber type

  • sensory

glossopharyngeal CN IX

• cranial nerve

• function

  • sense taste, move pharynx

• fiber type

  • mixed

hypoglossal CN XII

• cranial nerve

• function

  • move tongue

• fiber type

  • motor

vagus CN X

• cranial nerve

• function

  • visceral sensation from ventral cavity, pharynx and larynx muscles, parasympathetic motor innervation of viscera to regulate heart rate, breathing, and digestion

• fiber type

  • mixed

accessory CN XI

• cranial nerve

• function

  • move SCM and trapezius

• fiber type

  • motor

cervical enlargement

• where nerves in the cervical part reorganize and create a bulge in the spinal cord

lumbar part

• where nerves in the lumbar part reorganize and create a bulge in the spinal cord

conus medullaris

• where spinal cord proper ends (L2)

• nerves keep going down lumbar vertebrae and exit

• comes to a cone

cauda equina

• nerves at the end of the spinal cord

• looks like a horse tail

• continues down until exit

filum terminale

• little piece of CT that anchors cauda equina in place to bone of pelvis

functions of spinal cord

• spinal reflexes

• carry information to and from the brain

posterior segment

• vitreous chamber

• filled with vitreous liquid

• posterior portion of the eye

lens

• separates anterior cavity and posterior segment of the eye

• refracts light onto the retina

anterior cavity

• front portion of the eye

• cornea, lens, etc.

fibrous layer

• outer layer of the eye

  • cornea

  • sclera

cornea

• fibrous layer

• cone over anterior part of the eye

• transparent

• directs light to the retina

sclera

• fibrous layer

• white of the eye

• all around posterior chamber

• structural support and muscle attachment

vascular layer

• middle layer of the eye

• blood vessels to support the retina

  • choroid

  • ciliary body

  • iris

  • pupil

choroid

• vascular layer

• all around posterior chamber

• blood vessel supply

cillary body

• vascular layer

• choroid widens out above and below the lens

• muscles pull on ligaments attached to lens

• changes lens shape/incoming light reaching retina

pupil

• vascular layer

• center of iris, hole that light can pass through

retina

• inner layer of eye

  • pigmented layer

  • photoreceptor cells

  • bipolar cells

  • ganglion cells

  • optic discs

  • ora serrata