human brain has appoximately 100 billion neurons.
composition of cerebral spinal fluid (CSF)
- (99% water)
- *function-protects-oxygenated and cushions
- recieves information from the sensory receptors.
- send appropriate impulses, instrutions to the muscles and glands of the body.
- (muscle activity, movement)
peripheral nervous system
- portion of the nervous system that is outside the brain and spinal cord.
- peripheral nerves include the 12 cranial nerves, the spinal nerves are termed the autonomic nerves.
- nerves in PNS connectthe CNS to the sensory organs (eye and ear) other organs of the body, blood vessels and glands.
- 12 pairs cranial nerves
- 31 spinal nerves
system that accelerates the heart rate,constricts blood vessels,and raises blood pressure. tachy! (speed up)
system that slows the heart rate, increases intestinal and gland activity, and relaxes sphincter muscles. brady! (slow down)
- greek for dendron,whitch means tree.
- primarily recieve and integrate (mix and translate) incoming signals. taking notes! (recieve signals)
- *the first neurotransmitters ever identified was acetylcholine.
- *possible for messages to cross from the synapse of a neuron to target receptor.
- *keeps nerves communicating, fresh and stimulated.
- *influence muscle action.
- manufactured in the brian, where it performs its primary functions, 90% of our serotonin supply is found in the digestive tract and in blood platelets.
- relay messages to one part of brain to another.
white matter v. gray matter
- *white matter 60% of brain.
- has nerve fibers and has a myelin sheath which gives the fibers their white appearance.
- consumes 6% of brain oxygen.
- *gray matter 40% of brian.
- composed of neurons and a dense network of dendrites.
- portion of nerves does not have a myelin sheath and is gray.
- consumes 94% brain oxygen.
(csf) cerebrospinal fluid
- celebrospinal fluid acts as a cushion, protecting the brain and spinal cord from injury.
- 99% H2O (protiens,glucose,electrolytes)
- production is approximately 500ml's per day,turnover of total csf volumn is 3-4 times per day.
largest portion of the brain
- cerebrum or cerebral cortex
- the cerebrum consists of the cortex, large fiber tracts (corpus callosum) and deeper structures (basal ganglia (brake pedal), amygdala (emotions), hippocampus (memory).
adult brain weight
- approximately 1,300 to 1,400 grams (453 grams in a pound)
- 3 pounds
quanity of neurons
are the primary output apparatus (activate muscle activity)
a connection between the axon terminal and the dendrite of a neuron.
- thick, tough, outer most membrane of the meninges (covering, protecting).
- most important
daily production of CSF
production is approximately 500ml's per day,turnover of total csf volumn is 3-4 times per day.
cerebellum (latin for lil brain)
- 2nd largest part of brain.
- provides excitatory inputs (gas pedal) that are involved in coordinating movement, balance and motor learning.(stop dont go)
- (keeps the body in check)
- located deep w/i brain under the thalamus.
- factors such as blood pressure, body temp,hunger thirst, fluid/electrolyte balance, body weight, emotion and circadian rythms (sleep wake cycle) are held to a precise value called set point.
limbic system of the brain
- connect center
- a complex connection of brain regions deep w/i the brain underneath the temporal lobes.
- includes olfactory cortex
- helps file away new memories as they occur in to long term memory.
- significance of the hippocampus is driven hm by a famous patient named Henry Gustav Molaison (feb. 26,1926-dec. 2, 2008) AKA Patient H.M.
basal ganglia (stop texting in class)
overall function-is considered inhibitory as though it were putting on the brakes for the body. (jugment, decisions)
- midbrain, pons, and medulla oblongata.
- connect left/right hemesphere.
3rd cause of death in the US, behind diseases of the heart and cancer. 2011
ischemic (87%) or hemorrhagic (13%)
- ischemic (lack of oxygen) stroke occurs as a result of a obstruction w/i a blood vessel supplyig blood to the brain.
- hemorrhagic a bleed result from a weekend vessel that ruptures and bleeds into the surrounding brain.
CNA and Stroke symptoms
- right hemisphere
- paralysis on the left side of the body.
- vision problems.
- memory loss.
- left hemisphere
- paralysis on the left side of body.
- speech language problems.
- slow, cautious behavioral style.
- memory loss.
- inability to express lamguage Broca"s Aphasia, most ppl the Broca"s area is the lower part of the left frontal lobe.
- Dr. Paul Broca 1824-1880
occipital lobe (seeing)
located in the rear of the head and is a important region controlling sight, reading and visual images.
- 1in. long structure has long been linked with a person's mental and emotional state.
thalamus relay station
- *signals from all sensory system, with exception of smell, pass thru here on their way to the cerebral cortex, and the cortex itself uses it to relay signals to other parts of itself and down into spinalcord.
- *multi sensory inputs are processed by the thalamus, including those related to vision, touch, and hearing.
- *detecting the focus of are attention and screening out distracting stimuli.
cranial nerves 2
- lacrimal gland and nasal septum
short term memory
- left temporal lobe- (reading)
- verbal memory and specific language such as comprehension of word.
- right temporal lobe- (playing)
- visual memory, musical abilities and identify visual objects.
- A lobe of the brain which is located laterally and below the cerebrum. Contains auditory and receptive areas.
spinal cord length
- 45cm. xy male
- 43cm xx female
- Any of numerous olfactory filaments in the olfactory portion of the nasal mucosa that enter the olfactory bulb, where they terminate in synaptic contact with mitral cells, tufted cells, and granule cells.
- Also called first cranial nerve.