Chapter 15 (I did not make this)

major subdivisions of the brain

cerebrum, cerebellum, brainstem

cerebrum

two cerebral hemispheres which contain gyri (folds), sulci (grooves), and longitudinal cerebral fissure (big sulcus between hemispheres) connected by corpus callosum

gray matter of brain

- cortex (outer part) of cerebrum and cerebellum

- neurosomas

- dendrites

- unmyelinated axons

- synapses

white matter of brain

- deep in brain

- contain tracts made up of bundles of myelinated axons

Meninges of the brain

dura mater, arachnoid mater, pia mater

dura mater

tough, outer layer

dura layers within cranium

periosteal layer

meningeal layer

dural sinuses

superior sagittal sinus

transverse sinus

dural sheets that occupy spaces separating major parts of the brain

falx cerebi - between hemispheres

tentorium cerebelli - between cerebrum and cerebellum

arachnoid mater

transparent, middle layer, CSF, arachnoid granulations

pia mater

delicate, inner layer

lateral ventricles (2)

interventricular foramen

third ventricle (1)

cerebral aqueduct

fourth ventricle (1)

central canal of spinal cord

cerebrospinal fluid in ventricles

clear, colorless liquid

CSF production

choroid plexus (ependymal cells) within ventricles

CSF flow

within ventricles, down canals, and within subarachnoid space of the brain and spinal cord

CSF absorption

by arachnoid granulations back into blood at superior sagittal sinus

CSF provides

buoyancy, protection, & chemical stability

5 lobes of the cerebrum

frontal, parietal, occipital, temporal, insula

frontal lobe

(frontal bone to central sulcus) cognition, speech, and motor control

parietal lobe

(central sulcus to parieto-occipital sulcus) interprets signals of general senses and taste

occipital lobe

(parieto-occipital sulcus to occiptal bone) principal visual center

temporal lobe

(temporal bone to lateral sulcus) hearing, smell, learning, and memory

insula

(deep to lateral sulcus) taste, visceral sensation, and language

cerebral cortex

surface of hemispheres (40% of mass of the brain)

cerebral cortex cells

pyramidal cells (triangle shaped with apex pointing to brain surface) output neurons of cerebrum

vision

occipital lobe, primary visual cortex

hearing

temporal lobe and insula, primary auditory cortex

equilibrium

cerebellum, several brainstem nuclei

taste

parietal lobe, primary gustatory cortex

smell

temporal and frontal lobes, orbitofrontal cortex

precentral gyrus

primary motor cortex - exhibits somatotopy (a body map called motor homunculus)

postcentral gyrus

primary somatosensory cortex - exhibits somatotopy (a body map called sensory homunculus)

primary sensory cortex

first cortical region to receive input for that sense

primary motor cortex

issues projection fibers to distribute motor commands

association cortex

- Any cortical area that is not primary

- interpretation of sensations, thought, memory, and motor planning

- Prefrontal cortex

Language: Wernicke's area

posterior to lateral sulcus of left brain, recognition of written and spoken language

Language: Broca's area

inferior prefrontal cortex of left brain, speech

emotion

(several areas involved) amygdala outputs to hypothalamus and prefrontal cortex

cognition

(association areas of cortex) acquire and use knowledge

2 types of memory

procedural and declarative

memory

(limbic areas involved) amygdala creates emotional memories, hippocampus consolidates declarative long term memories

projection tracts

travel vertically to carry info between cerebrum and rest of body

commissural tracts

-Commissures cross between two hemispheres

-Corpus callosum is largest

association tracts

connect regions within same hemisphere

limbic system function

emotion and learning, contains gratification and aversion centers

prominent parts of limbic system

cingulate gyrus, hippocampus, amygdala

basal nuclei

deep masses of cerebral gray matter, involved in motor control

basal nuclei consists of

caudate nucleus, putamen, globus pallidus

Diencephalon

thalamus, hypothalamus, epithalamus

thalamus makes up...

4/5 of diencephalon

interthalamic adhesion

connects left and right thalami

Thalamus function

sensory gateway to the cerebral cortex - involved in sensation, memory, emotion, and some movement

Hypothalamus location

extends from optic chiasm to mammillary bodies

hypothalamus function

major control center of the autonomic nervous system and endocrine system

Epithalamus (pineal gland)

an endocrine gland

epithalamus (habenula)

relay from limbic system to midbrain

Epithalamus

forms the thin roof over the third ventricle

Brainstem

midbrain, pons, medulla oblongata

Midbrain posterior aspect

(tectum) tectal plate - 4 bulges consisting of superior and inferior colliculi

midbrain anterior aspect

- cerebral peduncles

- tegmentum w/ red nucleus

- substantia nigra (degenerates into parkinson's)

- cerebral crura anchor cerebrum to brainstem

cerebral aqueduct

passes through midbrain

- contains central gray matter

The midbrain gives rise to cranial nerves...

III and IV

pons anterior aspect

creates a large bulge

pons posterior aspect

contains peduncles that attach to cerebellum

pons

contain various tracts between spinal cord and the brain/cerebellum

The pons gives rise to cranial nerves...

V-VIII

medulla oblongata

extends from the pons to the foramen magnum of the skull (where it becomes the spinal cord)

important nuclei in medulla oblongata

cardiac center

vasomotor center

respiratory center

anterior surface bulges of medulla oblongata

Pyramids (medial) and Olives (lateral)

medulla oblongata gives rise to cranial nerves...

VIII, IX, X, XI

reticular formation

web of gray matter that runs through all levels of brainstem

reticular formation functions

somatic motor control

cardiovascular control

pain modulation

sleep and consciousness

habituation

cerebellum

cerebellar hemispheres (2)

- vermis in the center connecting them

arbor vitae of cerebellum

white matter

Deep nuclei of the cerebellum

gray matter

special neurons in cerebellum

purkinje cells

Alzheimer's disease (AD)

- Recent event memory loss

- Reduced attention span, disorientation

- Atrophy of gyri of cerebral cortex and hippocampus

- Neurofibillary tangles and senile plaques

Parkinson's disease (PD)

- Paralysis agitans

- Loss of motor function (tremors, shuffling gait, difficulty with movement sequences)

- Degeneration of dopamine-releasing cells from substantia nigra