Exam 1 neurosci flashcards

skull

boney framework of head, protect brain, 14 face bones, 28 adult teeth, 8 crainal bones

Cranium

portion of skull that encloses brain, fused bones (frontal, occiptial, ethmoid, sphenoid, 2 temporal, & 2 paretal bones)

How many bones make up the Crainum

8

name the bones that make up the cranium

frontal bone, occipital bone, sphenoid bone, ethmoid bone, 2 temporal bones, and 2 parietal bones

Sutures lines

Bone have fused- begin @ 2 months & complete @ 18 months

When do you palpate sutures in head

at 8 months

Which of the above is Not one of the three suture lines

lanbdoidal

what are fontanels

soft spots located between the cranial bones of fetus and newborn

what do fontanels do

allows skull to expand to accommodate the growing brain

When do the Fontelles harden

when the brain stops growing in size

where is the fossa

undersurface of brain

what are the three fossas

anterior cranial, middle cranial, posterior cranial

what is under the anterior cranial fossa

frontal lobe

what is under the middle cranial fossa

anterior inferior temporal

what is under the posterior cranial fossa

cerebellum

Which fossa has the most sharp edges

middle cranial fossa

Where is the meninges

Located between the skull & brain, cover the spinal cord

what do the meninges do

form a seal over CNS

list the order of meninges

dura mater, arachnoid mater, pia mater

What’s the dura mater

outermost meningeal layer, tough thick membrane, dural sinuses

whats the dural sinuses

veins located above the frontal & parietal lobes – act like a circulatory system & allow cerebral veins to empty into them

where does the cerebra veins recive CSF from

sub arachnoid space

what’s the blood supply to the dural mater

middle meningeal artery

How do we feel headaches?

through the dura matter as it has nerves

is the brain innervated by nervous sysyem

nope

Arachnoid mater is below what

subdural space

What does the subachnoid space hold

CSF

Pia mater

deepest layer, on gyri & sulci of the brain/spinal cord

cranial pia mater

ancord to brain via spinal cord

spinal pa mater

encloses spinal cord, attaches to dura mater

blood brain barrier

acts as wall for what comes from blood stream into CNS

ventricles

hollow spaces in the brain that has CSF

how many ventricles in brain

4

Each ventricle has _ horns

3

where does the anterior horn ventricle project too

frontal lobe

where does the inferior horn ventricle project too

temporal lobe

where does the posterior horn ventricle project too

occipital lobe

What does CSF do?

keeps toxin out, nourishes brain

When is hydrocephalus fatal

adulthood

how is hydrocephalus seen in infants

big head, neuro injury symptoms

how is hydrocephalus seen in adults

increased intercranial pressure, headache, vomiting, cognitive deteration

treatment for how hydrocephalus

shunt or craniotomy

How does normal pressure hydrocephalus present?

develops in adulthood (50-70yrs old), arachnoid villi cannot absorb CSF, unsteady gait, progressive dementia, urinary intontinence

neuron

electrically excitable nerve cells & fibers

cell body

Contains the nucleus – stores genetic codes of the organism

Dendrites

tree like processes attaching to cell body, receive messages from presynaptic neurons

Axon Hillock

Region where the cell body & axon attach, function as tight junctions between 2 cells

Axon

Fiber emerging from the hillock, transmits actional potentials (nerve signals) to terminal boutons

Myelin

covers axon, made of lipids, conducts nerve signals down the axon

Schwann cells

located in the peripheral nerves, able to be regenerated if damaged

Oligodendrocytes

located in brain & spinal cord, no regenerate

Nodes of Ranvier

Spaces between the myelin where nerve signals jump from one node to the next, able to generate the electrical activity needed for nerve conduction

synaptic cleft

Space between a presynaptic neuron’s terminal boutons & a postsynaptic neuron’s dendrites

Neurotransmitter

Chemical stored IN terminal boutons, released into the synaptic cleft to transmit messages

Presynaptic Neuron

First order neuron that releases its neurotransmitter in the synaptic cleft

Postsynaptic Neuron

Second order neuron, receives the presynaptic neuron’s neurotransmitter but only if the neurotransmitter possesses the specific binding molecules

gray matter

nucleus or groups of nuclei, processing and choice making, cell bodies, dendrites

white matter

Bundle of neuronal axons that travel together, myelin are glial cells that form fatty layers that appear white, communication highway

Glial cells

Provide nutrition & physical support that maintains the structure integrity of neurons

Support neuronal functions & have a role in synaptic communication

Facilitates cell migration in development of the nervous system

Astrocytes

Essential role in regulation of chem in the extracellular space, removes transmitter from synaptic cleft, control extracellular ion concentration to ensure proper neuronal function

what are the non-neuronal cells?

Microglia & Ependymal cells

Microglia

eliminates debris from dead & degenerating neurons & glial cells – plays a role in remodeling of synaptic connections

Ependymal Cells

line the ventricles of the brain & direct cell migration

Neuronal communication involves both electrical and chemical signaling, what does it do

which regulate synaptic activity and enable nervous system inhibition

what does neuronal communication involve?

electrical & chemical signaling

What is inhibition essential for?

motor control & behavior

Repetitive practice ____inhibitory processes, supporting accurate sensory and motor function, which can be impaired in neurological disorders.

strengthens

What is the neuromuscular junction?

is the synapse between a motor neuron and a skeletal muscle fiber

When an action potential reaches the axon terminal of the motor neuron, it triggers the release of the ___

neurotransmitter acetylcholine (ACh)

Where is ACh released?

synaptic cleft

What are action potentials

A brief electrical impulse provides the basis for the conduction of nerve signals along the axon

Due to changes in sodium & potassium ions

What does a membrane protein do?

helps maintain a cells resting potential

Astrocytes

Essential role in regulation of chemical reactions in the extracellular environment

remove neurotransmitters from the synaptic cleft

Control extracellular ion concentration to ensure proper neuronal function

Microglia

eliminates debris from dead & degenerative neurons & glial cells, plays a role in remodeling of synaptic connections

Ependymal Cells

line the ventricles of the brain & direct cell migration

Neuronal Communication

involves both electrical and chemical signaling, which regulate synaptic activity & enable nervous system inhibition

Inhibition

essentially for precise motor control & behavior, preventing errors like overshooting or incoordination

Neurotransmitters

released into the synaptic cleft trigger postsynaptic potentials either excitatory or inhibitory

Repetitive practice strengthens what

inhibitory processes, supporting accurate sensory & motor function which can be impaired in neurological

Neuromuscular junction

synapse between a motor neuron and a motor neuron & a skeletal muscle fiber

What happens when an action potential reaches the axon terminal of the motor neuron?

It triggers the release of acetycholine (ACh)

What does acetycholine (ACh) binding to the neuromuscular junction initiates?

a muscle contraction

CNS

Brain & spinal cord

PNS

Nerves branching from the brain & spinal cord to the body

PNS to CNS

Sensory input is sent to the CNS

CNS to PNS

The CNS processes the input & sends motor out (move hand) back through the PNS

Afferent Axons

Carry information from peripheral receptors towards CNS

Efferent Axons

Carry information away from the CNS

Endoneurium

separates individual axon

Perineurium

surrounds bundles of axons (fascicles)

Epineurium

encloses the entire nerve

Schwann cells

makes up myelin sheath

unmyelinated

smaller diameter axons

Myelinated

larger diameter axons

Cutaneous Branches

Supply skin & subcutaneous tissues (not purely sensory)

Muscular Branches

Supply muscles, tendons & joints

Cervical Plexus

Cutaneous sensory info from posterior scalp to clavicle, innervates the anterior neck muscles & diaphragm

-phrenic nerve

Brachial Plexus

Entire upper limb is innervated by branches

-Radial N. Axillary N., Ulnar N., Median., Musculocutaneous N.,N.

Lumbar Plexus

Innervate skin & muscles of the anterior & medial thigh

Saphenous N innervates medial leg & foot

Sacral Plexus

Innervates posterior thigh & most of the leg & foot

contains parasympathetic axons in addition to the somatic axons