chapter 11, sections 11.1-11.4

makeup of brain

2 cerebral hemispheres, diencephalon, brainstem, cerebellum

meinges

membranes that protect brain and spinal cord, lie between bone and soft tissue of nervous system

3 layers of the meninges

dura mater, arachnoid mater, pia mater

dura mater

outer layer, dural sinuses, epidural space

what tissue is dura mater

dense connective tissue

arachnoid mater

middle layer, web-like, subarachnoid space contains cerebrospinal fluid (CSF)

pia mater

inner layer, attached to surface of brain and spinal cord, contains blood vessels and nerves, nourishes cns

what ventricles are csf produced in

2 lateral ventricles (first and second), third ventricle, fourth ventricle

what are ventricles continuous with

central canal of spinal cord

interventricular foramina

connect third to lateral ventricles

cerebral aqueduct

connects third and fourth ventricles

what secretes csf

choroid plexuses, special capillaries of pia mater covered by ependymal cells

how is csf formed

selective transfer of substances from the blood

cerebrospinal fluid

nutritive and protective of cns neurons, helps maintain stable ionic concentrations in cns

what is csf absorbed by after exchanging substances

arachnoid granulations

volume of csf

about 140mL at any time

what gives rise to cns

neural tube

3 cativies (vesicles) of brain

forebrain, midbrain, hindbrain

what does the forebrain divide into

telencephalon and diencephalon

what does the hindbrain divide into

metencephalon and myelencephalon

forebrain in mature brain

cerebrum, basal nuclei, and diencephalon

hindbrain in mature brain

cerebellum, pons, medulla oblongata

where is the telencephalon produced

lateral ventricles

where is diencephalon produced

third ventricle

where is mesencephalon produced

cerebral aqueduct

where is metencephalon produced

fourth ventricle

where is myelencephalon produced

fourth ventricle

what is the largest part of the brain

cerebrum

cerebral hemispheres

2 halves, separated by flax cerebri

corpus callosum

connects cerebral hemispheres

gyri

ridges or convolutions

sulci

shallow grooves in surfaces, like central sulcus

fissures

deep grooves in surface

longitudinal fissures

separate the cerebral hemispheres

transverse fissures

separate cerebrum from cerebellum

5 lobes of the cerebral hemispheres

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

insula (island of reil)

deep within lateral sulcus

cerebral cortex

thin layer of gray matter, which makes up outermost layer of all outer lobes of the cerebrum

how much neuron cell bodies does cerebral cortex contain

almost 75% of neuron cell bodies

white matter of cerebrum

lies under cerebral cortex, makes up most of cerebrum, contains bundles of myelinated axons

what do bundles of myelinated axons do in white matter

connect neuron cell bodies in cerebral cortex to other portions of nervous system

what can the cerebral cortex be divided into

sensory, association, and motor area, some overlap exists

cutaneous sensory area

parietal lobe, interprets sensations on skin

where is sensory speech area (wernicke’s area)

temporal/parietal lobe, usually left hemisphere

sensory speech area (wernicke’s area)

understanding and formulating speech

visual area

occipital lobe, interpets 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

association areas

regions that are not motor or sensory, connect to each other and to other brain structures

what do association areas provide

memory, reasoning, verbalization, judgement, emotions

frontal lobe association areas

concentrating, planning, complex problem solving, emotional behavior, judging consequences of behavior

parietal lobe association areas

understanding speech, choosing words to express thoughts and feelings

temporal lobe association areas

interpret complex sensory experiences (understanding speech, reading), store memories of visual scenes, music, and complex patterns

occipital lobe association areas

analyze and combine visual images with other sensory experiences

insula (association)

translating sensory information into proper emotional responses

primary motor areas (motor cortex)

control voluntary muscles, ost nerve fibers cross over in brainstem

where is motor cortex

frontal lobes

broca’s area location

anterior to primary motor cortex, usually in left hemi

frontal eye field

controls voluntary movements of eyes and eyelids

frontal eye field location

above broca’s area

which hemisphere is dominant in most people

left

dominant hemisphere controls

language skills of speech, writing, reading; verbal, analytical, and comutational skills

nondominant hemisphere controls

nonverbal tasks, motor orientation in space, understanding and interpreting musical and visual patterns, emotional and intuitive though processes

short term (working memory)

neurons connected in a circuit, circuit is stimulated over and over

memory consolidation

short term memory into long term

what happens when impulse flow ceases in working memory

memory ceases also

long term memory

changes structure or function on neurons, makes new synaptic connections by increasing branching of processes

long term potentiation

increase in neurotransmitter release and effectiveness of synaptic transmission upon repeated stimulation

basal nuclei (basal ganglia)

product dopamine, control voluntary movement

contents of basal nuclei

consist of caudate nucleus , putamen, and globus pallidus

diencephalon

composed of gray matter

diencephalon location

between cerebral hemispheres and above the brainstem, surrounds the third ventricle

portions of the diencephalon

thalamus, hypothalamus, optic tracts, optic chiasma, infundibulum, posterior pituitary, mammillary bodies, pineal gland

what does thalamus not receive senses of

smell

hypothalamus

maintains homeostasis, links nervous and endocrine

limbic system

controls emotional responses, feelings, behavior oriented toward survival, reacts to life-threatening upsets (physical or psychological)

parts of brainstem

midbrain, pons, medulla oblongata

brainstem

contains nerve fiber tracts and gray matter masses

midbrain

short section of brainstem, contains bundles of fibers that join lower parts of brainstem and spinal cord with higher brain

midbrain location

between diencephalon and pons

parts of midbrain

cerebral aqueduct, cerebral peduncles, corpora quadrigemina, red nucleus

cerebral peduncles

main motor pathways that connect cerebrum to lower portions of nervous system

corpora quadrigemina

centers for visual and auditory reflexes

red nucleus

role in postural reflexes

pons

relays nerve impulses between medulla and cerebrum, relays impulses from cerebrum to cerebellum, regulate breathing

medulla oblongata

conducts impulses between brain and spinal cord, contains various non vital reflex control centers (coughing, sneezing, swallowing,vomiting)

what control centers does medulla have

cardiac, vasomotor, respiratory

reticular formation (reticular activating system)

complex network of nerve fibers scattered throughout brainstem, connects to control centers, filters incoming sensory info, passing some to cerebral cortex and discarding unimportant info, wakefulness

where is reticular formation

in brainstem and extends into the diencephalon

non-REM sleep

slow wave, restful, reduced blood pressure and respiratory rate, 3 stages, alternates with REM sleep

REM sleep

paradoxical sleep (some areas of brain are active), heart and respiratory rates irregular, dreaming

cerebellum location

inferior to occipital lobes, dorsal to pons and medulla

what connects hemispheres of the cerebellum

vermis

what matter in cerebellar cortex

gray matter

arbor vitae

white matter

parts of cerebellum

cerebellar peduncles, dentate nuscleus (largest nucleus)

cerebellum

integrates sensory info concerning position of body parts, coordinates skeletal muscle activity, maintains posture

what do recent studies suggest about the cerebellum

that it can interact with other parts of the cerebral cortex, such as the limbic system and the auditory areas

brain waves

recordings of fluctuating electrical changes in the brain