Central Nervous System:

(CNS)

Contains: Brain & Spinal Cord

Peripheral Nervous System:

(PNS)

Contains: Nerves -- Cranial (12 pair), Spinal Cord (31 pair)

Sensory Nerves

Afferent, start from all over the body, end up in CNS.

Motor Neurons:

Efferent, start from CNS, end up in muscles & glands.

Somatic Nervous System

Voluntary function, skeletal muscles.

Autonomic Nervous System

Involuntary function, cardiac/smooth muscles, and glands.

Sympathetic NS / Emergencies:

fight/flight, digestive & urinary system shuts down.

Parasympathetic NS / Emergencies:

Calms down the body, stimulates digestive & urinary system.

Neurons:

Main cells, makes/conducts nerve impulses.

Neuroglial / glial cells:

Support, connect, protect and provide nutritional support.

What are the 6 types of Neuroglial/ glial cells?

-Astrocytes

-Oligodendrocytes

-Schwann Cells

-Ependymal Cells

-Microglial cells

-Satellite Cells

Astrocytes:

star shaped, blood brain barrier

Oligodendrocytes:

make myelin around nerves in CNS

Schwann Cells:

make myelin around nerves in PNS.

Ependymal Cells:

have cilia, line fluid filled cavities in CNS.

Microglial Cells:

phagocytosis

satellite cell:

protect the body of the neurons.

Neurons:

Basic structural/ functional units of the nervous system.

What are the different components in Neurons?

Dendrites to body to axon.

Dendrites: short, branched, multiple

Body: Soma, contains nucleus (DNA)

Axon: Long, always one.

Synapses:

Communication, two neurons get close to communicate.

What is the gap between two neurons?

Synaptic cleft

How do two neurons communicate?

1. Nerve impulse goes from A-->B

2. End of nerve, chemical (neurotransmitter)

3. Neurotransmitter: sticks to neuron & stimulates nerve impulse.

4. After communication, NT gets sent back to nerve.

Presematic Neuron: beginning

Postsematic Neuron: aftermath

Neurotransmitter:

Chemicals which make communication between two neurons possible.

Excitatory / Stimulatory:

"green traffic light", let's nerve impulses pass.

Inhibitory:

"red traffic light", stops nerve impulses.

-enkephalines & endorphins = natural painkillers

-gaba : inhibitory neurotransmitter which brings down the mood (depression).

Meninges:

Membrane covering the brain / spinal cord for protection.

Layers of the meninges:

-Skin

-Bone

-Epidural Space

-Dura Mater: has blood vessels, outermost layer.

-Subdural Space

-Arachnoid Mater: Thin, branched, No blood vessels

-Subarachnoid space (contains CSF)

-Pia Mater: Innermost layer, attached to brain and spinal cord.

Different components in the brain:

-Cerebrum

-Cerebellum

-Diencephalon

-Brain Stem

Cerebrum:

largest highest part of brain, only part of brain that has voluntary function

-gyri: bulging areas

-sulci: depressed areas

-fissures: deep crack

Longitudinal Fissure (In cerebrum)

separates brain into L & R hemispheres.

L hemisphere:

dominant one, verbal communications & analysis

R hemisphere:

non-dominant, non verbal communications, emotions, artistic abilities (painting & music)

Cerebrum works _____, L controls R, R controls L

Contralateral

Each hemisphere has _____ lobes, ____ all together>

2 lobes, 8 all together

Frontal Lobe:

largest lobe, personality, behavior, controlling movement, problem solving,

(left frontal lobe: broca's area (speech))

Parietal Lobes:

Skin Senses

Temporal Lobes:

Hearing, memory, some emotions, sensory speech

(left temporal lobe: language comprehension)) -- Wernike's Area

Occipital Lobe:

Vision, Visual perception

Corpus Callosum:

Nerves going left/right, people who have wider ones can multitask.

Cerebellum:

2nd largest part of brain, located in the back of the brain, below occipital lobe.

helps w balance, posture, and coordination.

Cerebellum works _____. L controls L. R controls R.

*L and R lobe connected by the vermis

Ipsilateral.

Diencephalon:

contains thalamus, hypothalamus, and epithalamus.

Thalamus:

Relaying center of the brain, conscious awareness of some senses. (Pain and Temperature)

Hypothalamus:

Makes hormones, helps homeostasis: temperature, thirst, electrolytes, hunger, blood glucose, heart rate, sleep and wakefulness.

Epithalamus:

Pineal gland: melatonin, sleep hormone... melatonin goes up at night, down during the day.

Pituitary Gland

Brain Stem:

contains CN III TO XII , lowest part of brain, vital center of brain , has 3 parts: midbrain, pons, medulla oblongata

midbrain:

reflex movement of head/neck in response to sound.

Pons:

Respiration

-Respiratory rate

-Depth of respiration

Medulla Oblongata:

Heart control center

-Heart rate

Heart rhythm

-Respiratory control center: inspiration center & expiration center

-vasomotor: controls blood pressure

CN I

Olfactory Nerve: Smell

CN II

Optic Nerve: Vision

CN III

Oculomotor Nerve: moves eyeball, up, down, medial

CN IV

Trochlea: rolling eyes

CN V

Trigeminal: largest CN, sensory of face, 3 branches

CN VI

Abducens: lateral movement of the eyeball

CN VII

Facial Nerve: face movement, taste

CN VIII

Vestibulocochlear: hearing and balance

CN IX

glossopharyngeal nerve: swallowing food

CN X

vagus nerve: longest nerve, all visceral organs (chest, abdomen, and pelvic), parasympathetic

CN XI

accessory: shoulder

CN XII

hypoglossal nerve: moving tongue, speech