A&P- Brain Test

Meninges

membranes that protect the brain and spinal cord; lie between bone and soft tissues of nervous system; 3 layers

3 layers of meninges

dura mater, arachnoid mater, pia mater

dura mater

thick dense connective tissue, outermost layer of the meninges.

-Dural sinuses and epidural space.

arachnoid mater

middle layer; weblike

subarachnoid space contains CSF

pia mater

Innermost layer of the meninges, attached to surface of brain, spinal cord

blood vessels and nerves

nourishes CNS

What is CSF

fluid produced in 4 ventricles of the brain

aids in the selective transfer of substances from blood to CSF

-provides cushion and nutrients to the brain

-maintains stable ionic concentrations in the CNS

-circulates in ventricles, central canal of spinal cord, and subarachnoid space

- takes waste away from brain

-important in immune & metabolic function

What are ventricles?

-ventricles are interconnected cavities within cerebral hemispheres and brain stem

-ventricles are continuous with central canal of spinal cord , filled with CSF

What are the 4 ventricles of the brain?

2 lateral ventricles (1st and 2nd)

3rd ventricle

4th ventricle

What are the major portions of the brain?

cerebrum, diencephalon, cerebellum, brainstem

What is the structure of the cerebrum?

* Cerebral Hemispheres ( 2 Right/Left)

* Corpus Callosum

* Gyri ridges

separated by

* shallow grooves: sulci

*fissures:(deep grooves in surface) logitudinal, transverse

5 lobes of cerebral hemispheres

frontal, parietal, temporal, occipital, insula(island of reil)

corpus callosum

connects cerebral hemispheres, bottom crease of a wrinkle

gyri

ridges of the brain. Raised part of a wrinkle

Sulci

shallow grooves that separate gyri

fissures

deep grooves in the surface of brain

longitudinal- separates cerebral hemispheres

transverse- separates cerebrum from cerebellum

lobes of cerebral hemispheres

1. Frontal

2. Parietal

3. Temporal

4. Occipital

named after the bones that underlie them

frontal lobe

responsible for concentrating, planning, complex problem solving, and judging consequences of behavior

motor areas control movements of voluntary skeletal muscles

parietal lobe

sensory areas provide sensations of temperature. touch, pressure, and pain involving the skin

association areas function in understanding speech and in using words to express thoughts and feelings

temporal lobe

sensory areas are responsible for hearing

association areas interpret sensory experiences and remember visual scenes, music, and other complex sensory patterns

occipital lobe

sensory area responsible for vision

association areas combine visual images with other sensory experiences

cerebral cortex

thin layer of gray matter, makes up outermost layer of cerebrum

contains 75% of neuron cell bodies in nervous system

white matter of cerebrum

Lies under cerebral cortex

Makes up most of cerebrum

Contains bundles of myelinated axons, that connect neuron cell bodies in cerebral cortex to other portions of nervous system

cutaneous sensory area of cerebral cortex

-parietal lobe

-interprets sensations on skin

(Wernicke's area)

-temporal/parietal lobe

-usually left hemisphere

-understanding and formulating language

visual area

occipital lobe, interprets vision

auditory area

temporal lobe, interprets hearing

sensory area for taste

Near base of the central sulcus

Includes part of insula

Sensory area for smell

arises from centers deep within temporal lobes

Olfactory Bulb

Motor areas of the cortex

primary motor cortex; Broca's area;

frontal eye field

primary motor area

frontal lobe, controls voluntary muscles

most nerve fibers cross over brainstem

Broca's area

-anterior to primary motor cortex

-usually in left hemisphere

-controls muscles needed for speech, actually talking

frontal eye field

Above Broca's area

Controls voluntary movements of eyes and eyelids

parts of the brain stem

midbrain, pons, medulla oblongata

parts of diencephalon

thalamus, hypothalamus, (epithalamus as well)

Thalamus

structure in the center of the brain that acts as a primary relay station for sensory and motor signals traveling to the cerebral cortex.
roles in memory, emotion, and wakefulness/alertness

hypothalamus

located below the thalmus. controlling body temperature, thirst, hunger, SLEEP/WAKE cycles

medulla oblongata

lowest part of brainstem, responsible for regulating INVOLUNTARY body functions such as breathing, heartrate, blood pressure, and digestion. also reflexes and moto pathways