Neuro ch 3 exam

smooth muscle

smooth muscle

Intestines/Arteries

Cardiac Muscles

muscles found in the walls of your heart

Muscle Fibers

Bungee cord made of fibers. Activated at the Neuromuscular Junction

Neuromuscular Junction Parts

Axon, Ionotropic Receptors, Synaptic Vescicle, Synaptic Cleft, Muscle Fiber

First step to telling a muscle to move

Brain neurons fire APs

Execution(muscle movement)

Spinal cord motor neurons control muscles. One AP= one contraction

Rubrospinal tract

Red nucleus -> medulla -> spinal cord

NT released with Nocireceptors

Substance P

Spiral Ganglion cells

hand off cells from ear to brain

Dorsal cochlear nucleus auditory pathway

DCN, inferior colliculus, MGN (thalamus), auditory cortex

Vestibular system function

motion, posture, balance, head position, spacial orientation

Semicircular Canals (vestibular system) detects

spinning

Lens

transparent disk that changes shape

Layers of LGN Temporal Retina goes to

2,3,5

Skeletal Muscles

the muscles attached to bones that enable you to move

Neuromuscular Junction

Where a nerve touches a cell

Striations

stripes formed by myofilaments inside myofibrils.

What does Ca2+ do in contractions

moves troponin and tropomysin out of the way

Motor cortex structure

M1, PMA, SMA (Strategy)

Pacinian corpuscle

Largest receptive field, detects vibration on hands

A1 fibers

initial sharp pain, quick adapting

stapes

"stirrup"

Lens shape for close vision

Wide shape

Photoreceptors in Light

Opsin activates, retinal changes shape, Transducin closes Na+ channels and hyperpolarizes the cell

Direction Selectivity

Determines object direction

Second step to telling a muscle to move

travel from the brain, through the spinal cord, to the muscle

third step to telling a muscle to move

axon terminals release acetylcholine at synaptic cleft

fourth step to telling a muscle to move

acetylcholine causes Na+ ion channels to open the muscle

fifth step to telling a muscle to move

Na+ entry causes Ca2+ to enter the muscle cell

sixth step to telling a muscle to move

Ca2+ pushes away the proteins blocking muscle movement

seventh and final step to making a muscle move

Muscle fibers pull each other and shorten the muscle

Myofilaments

Myosin and Actin

Myofibrils/sarcomeres

I-band, A-band and H-band

Sliding filament model

When the troponin/tropomysin are moved and ATP pulls and shortens the sarcomeres.

Lower Motor Neurons use

Commands muscle contraction.

Lower Motor neurons types

Alpha and gamma motor neurons

Alpha motor neurons

Moves powerful fibers, higher firing rate= stronger contractions

Gamma motor neurons

moves less powerful fibers, higher firing rate= stronger contractions

Motor unit

1 alpha neuron and connected fibers

Motor pool

all of the motor neurons that innervate the fibers of a single muscle

Flexors vs extendors

flexors bend limb, extendors extend them

Myotactic Reflex

Causes contraction of a muscle being stretched
Also called stretch reflex

Strategy (muscle movement)

Basal ganglia link reward signals to activities that can obtain rewards

Tactics(muscle movement)

Cerebellum fine-tunes movement with motor cortex. Error correction

Corticospinal Tract

Motor cortex->thalamus->cerebral peduncle->medulla base->Spinal cord

ventromedial pathways control

Balance and posture

The two Lateral Pathways

corticospinal tract and rubrospinal tract

M1

Primary motor pathway

PMA

Premotor area, neurons fire here before movement

SMA

supplemental motor area

Corticostriatal loop

Basal ganglia -> thalamus -> premotor cortex (choosing an action)

Basal Ganglia loop

Cerebral cortex -> striatum -> Globus pallidus -> thalamus

Corticocerebellar loop

Cerebellum -> thalamus -> primary motor cortex

Corticocerebellar loop job

Refines movement

Epidermis

Outer, dry, protective skin layer

Dermis

inner skin layer with nerves and blood vessels

Skin Mechanoreceptors activation

Activated by stretching or cell movement of actin

Merkel's disk

Slow adapting (generate a sustained AP frequency)

Meissner's corpuscle

on fingers, small receptive field, fine tuned movement

Corpuscles

Fire rapidle, quick adapting

C fibers

lasting dull pain, slow adapting

Dermatomes

Spinal Segments

Medial Lemniscal Pathway

Dorsal column, medial lemniscus (medulla), thalamus, S1

Medial Lemnsical pathway function

Touch/vibration

Trigeminal Touch pathway

Pons, thalamus, S1

Trigeminal touch pathway function

Moving face (cranial nerves)

Nocireceptors

Pain receptors

Mast Cell function

release histamine

Prostoglandins function

indicates cell death

Spinothalamic pathway

Spinal cord, medulla, thalamus, S1

TRP Channels

Channels that register temperature

TRPV1

The TRP channel hot peppers bind to

Frequency

the number of complete wavelengths that pass a point in a given time

Intensity

Air pressure

Pinna

The visible ear

Auditory Canal

entrance to the ear

tympanic membrane

the ear drum

malleus

"hammer"

incus

"anvil"

The three ossicle bones

malleus, incus, stapes

Footplate

Bottom of stapes, moves oval window

Oval window

membrane that leads from middle ear to inner ear

cochlea

snail-shaped structure of the inner ear that is filled with fluid

Organ of corti

Center part of the cochlea, containing hair cells, canals, and membranes

Scala media

Middle chamber of the cochlea; filled with endolymph (has organ of corti in it)

three fluid filled chambers of the cochlea

Scala media, scala vestibuli, scala tympani

Auditory vestibular nerve

Cranial nerve VIII, consisting of axons projecting from the spiral ganglion to the cochlear nuclei

Eustachian Tube

nasal cavity connection to middle ear

Stereocilia

hairlike extensions on the tips of hair cells in the cochlea that initiate the release of neurotransmitters when they are flexed

Depolarization of stereocilia

Endolymph bends stereocilia, K+ goes in, Ca2+ goes in, glutamate is released activating spiral ganglion cells

ventral cochlear nucleus auditory pathway

VCN, superior olive, inferior colliculus, MGN (thalamus), auditory cortex

Phase locking

the consistent firing of an auditory neuron at the same phase of a sound wave

Tonotopy

spatial arrangement of where sounds of different frequency are processed in the brain

Interaural time delay

time taken for sound to reach from ear to ear

otolith organs function

forward, back, left, right

Otolith organs

Otoconia, Kinocillium

Otoconia

calcium carbonate crystals that move in direction with you

Kinocillium

Tallest sterocilium of the hair cell

Semicircular canals (vestibular system)

The three hollowed tubes in the inner ear filled with endolymph. Has clustered hair cells

Cornea

External surface of eye