Neuroanatomy

grey matter

isolated centers of grey matter and neuronal soma within the white matter of the cerebrum

diencephalon

interthalamic adhesion

relay center, primarily for afferent signals en route to the cortex

• cuadate nucleus
• lentiform nucleus

grey matter

• it is a C-shaped structure that starts anterior to the lentiform nucleus
• stretches superiorly and posteriorly over the thalamus
• descends and runs anteriorly, inferior to the lentiform nucleus
• tail never touches thalamus

oval or "lens" shaped...

• Putamen
• Glubus palladius (palladium)

putamen

globus palladius

inferior portion of the caudate nucleus head

grey neuronal soma and axons

caudate nucleus

internal capsule

strands that connect the two nuclei cause a striped appearance

• grey matter, but a lighter grey than putamen
• has some myelinated fibers

a thin strip of white matter

grey matter and neuronal cell bodies

lateral to the lentiform nucleus

UNKNOWN

the external capsule (made of white matter)

the extreme capsule

insular cerebral cortex

white matter fibers

• grey matter
• it is a nucleus

emerges from the anterior end of the tail of the caudate nucleus

• limbic system
• visceral changes to emotions, pain, and fear respone

cerebral cortex of the medial temporal lobe

• neuronal soma
• grey matter axons

to the fornix

• deep temporal lobe
• starts anteriorly and extends posteriorly

the fornix takes information from the hippocampus to other parts of the brain, specifically to the mammillary bodies

involved in transfroming short-term memories into long-term

limbic system of brain

the crura (singular is crus)

commissural attachments

the corpus callosum

diencephalon

columns

white matter

the septal nuclei of the frontal lobe

mammillary bodies of the diencephalon

processing memories

• white matter axons that enter the cerebrum from the thalamus
• white matter axons leaving the cerebrum for the diencephalon, brainstem, and spinal cord

it runs between the superior portions of the putamen and caudate nuclei

runs between the putamen and the thalamus

the most posterior portion of the posterior limb of the internal capsule

LGN of the thalamus

the most posterior portion of the internal capsule, posterior to the lentiform nucleus

the two cerebral peduncles of the midbrain

• collection of white matter fibers that project from the internal capsule to the cerebral cortex, or vice versa
• basically an extension of the internal capsule

• white matter fibers that connect different parts of the cerebrum within the same himispheres
• two types: long and short

white matter fibers that connect areas of cerebral cortex from different gyri within the same cerebral lobe

white matter fibers that connect areas of the cerebral cortex from different lobes within the same cerebral hemisphere

• white matter fibers that connect portions of the cerebral cortex in one hemisphere with its partner in the other hemisphere
• there are only four cerebral commissures: corpus callosum, anterior commissure, posterior commissure, and habenular commissure

corpus callosum

• rostrum (most anterior)
• genu (knee or bend)
• trunk or body
• spenium (most posterior)

perpendicular, so they are not the same thing, but they do pass through it.

• olfactory tracts to each other
• limbic system to both halves

decussate axons from the pretectal nuceli travelling ton the Edinger-Westphal nucelus

• between the temporal lobe and the thalamus edges
• superior to the posterior midbrain

the edge between the frontal lobe and the thalamus

superior to the posterior commissure

axons from the habenular nucleus to go to the contralateral thalamus

corona radiata and internal capsule

• coordination, grading, learning, planning, and regulating of fine motor activity
• maybe some emotional movements

excitatory afferent

• primary motor cortex (excitatory)
• somatosensory cortex (excitatory)
• thalamus (excitatory)
• nigrosstriatal fibers from the substantia nigra of the brainstem (inhibitory)
• all over the cerebral cortex

glutame

glutame

inhibitory

• substantia nigra
• globus palladius

• inhibitory
• connection pathway called "striatonigral" fibers

• thalamus
• subthalamus
• midbrain

• excitatory
• this completes a loop...

GABA

• fibers traveling from the substantia nigra to the corpus striatum that release dopamine
• this causes an inhibitory effect on the corpus striatum

• fibers that travel from the corpus striatum to the substantia nigra and release GABA
• this causes an inhibitory effect on the substantia nigra

movement problems

filters information from the cortex, returns it to the cortex which then sends it to spinal cord or cranial nerves

striatonigral axons degenerate, causing the substantia nigra to be oeveractive and inhibit the corpus striatum too much

hereditary, autosomal dominant

• involuntary twitching (when staying still)
• immobility
• death

• it is a residual effect from Rheumatic fever that causes an autoimmune disease
• overactive immune system attacks basal nuclei neurons

• twitching
• jerky movements
• usually not too serious and can recover

• nigrostriatal neurons die
• corpus striatum is no longer inhibted and is overactive

• jerky movements
• hunched over due to flexor muscles being activated
• difficulty in stopping or starting movement
• tremors occur when they move

60%

• L-dopa (dopamine that crosses blood-brain barrier)
• MAOI (monoaminoxidase inhibitors)
• implant neurons that release dopamine
• remove globus palladius (last resort)

• hippocampus
• fornix
• mammillary bodies
• anterior thalamic nuclei
• amygdalae
• olfaction system
• cingulated gyrus
• parahippocampal gyrus

• transforming short-term memory into long-term memory
• controlls interaction between the autonomic nervous system, endocrine system, and emotions

• Cingulate cortex
• Parahippocampal gyrus
• Hippocampus
• Mammillary bodies
• Anterior nucleus of the thalamus

• motor decision making
• sentence structure in speech
• emotions
• autonomic reaction to emotions
• bladder control

pain perception

• parahippocampal gyrus
• this then becomes the hippocampus

• memory transmission
• little computation

anterior nucleu of the thalamus

the anterior cingulate gyrus

amygdala

• olfactory tracts
• septal nuclei
• diencephalon
• midbrain

it is not part of the papez circuit

• early, fearful amygdaloid reactions to stimuli before the hippocampus was fully developed
• basically, you feel fear for something but don't remember why you first felt it

• strong inputs to te amygdala from cerebral cortex after intense sensation
• can affect hippocampus and long-term memory
• flashbacks are triggered by certain stimuli

yes, because the visual cortex is connected to the amygdala

• nucleus of cholinergic fibers that release acetylcholine to all areas of the cerbral cotex when person is awake
• makes brain more sensitive to excitation
• this aids in learning

Alzheimer's disease

• loss of pyramidal neurons
• Amyloid plaques
• neurofibrillary tangels
• loss of cholinergic neurons from basal nuclei of Meynert

take motor information from the precentral gyrus to the striated muscles

• located in the hippocampus and amygdala
• they are abnormal clumps of microtubules

• starts in medial temporal lobe and moves superiorly
• then moves occipitotemporally
• finaly, frontal lobe functions dwindle by 3 years of onset
• personality degrades about 5-6 years before death

• forgetfulness, attention deficit
• inability to read, write, or recognize family
• vacant state
• personality degradation

cell phone usage correlates with lower amyloid plaques

• membranes that surroind the CNS, support it, and protect it
• Dura mater
• Arachnoid mater
• Pia mater

dura mater

• outer endocranial layer
• inner meningeal layer

bone (skull)

middle meningeal branch of the maxillary artery

dural sinuses

falx cerebri of inner meningeal layer of dura mater

• it runs in the midsaggital line of the cranium from frontal bone to occipital bone above the corpus callosum
• ends on the tentorium cerebella

tentorium cerebelli

• starts on occipital protuberance above the confluence of sinuses
• runs parallel with the transverse sinus along the petreous temporal bone
• ends on the posterior clinoid processes of sella turcica
• pretty much a 300 degree structure with a big whole in the middle

on the lateral sides of the posterior rim (dorsum sellae) of the sella turcica

the tentorial notch of the tentorium cerebelli

the tentorial notch is sharp and can cause damage to structures when there is extra pressure

diaphragma sellae

the infundibulum that connects the pituitary gland to the hypothalamus

anterior junction of the tentorium cerebelli and the falx cerebri

endosteum

inner meningeal layer

the inner meningeal layer of the dura

• pools between the dura and arachnoid maters
• called a subdural hematoma

• a space that only exists if conditions are right, such as a blow to the pterion
• the actual formation of it is usually a bad thing

arachnoid villi (also called granulations) penetrate the inner meningeal layer of the dura into the dural sinuses and CSF leeks through this penetration

subarachnoid space

webby-looking processes that stretch between arachnoid mater and pia mater

to act as a shock absorber through the stretchy processes of the arachnoid mater and the CSF contained in it

cisterna; arachnoid mater does not follow sulci of cerebrum

• Cisterna cerebellomedullaris (between the cerebellum and medulla)
• Cisterna interpeduncularis (between the cerebral peduncles)
• Cisterna pontis (between the medulla and the pons)
• Cistern of great cerebral vein

pia mater

the CNS; it follows sulci and gyri of the brain and spinal cord intimately

invaginations of the pia mater

ventricles of the brain

• Left and right lateral ventricles
• Third ventricle
• Fourth ventricle

• anterior
• occipital
• inferior (temporal)

interventricular foramena (right and left)

• between the right and left diencephalon
• the interthalamic adhesion passes through center of it

the cerebral aquaduct

• pons and medulla of brainstem make up anterior border
• cerebellum is posterior border

• right and left lateral apertures
• median aperture

• active, pressure independent
• constantly occuring in the choroid plexi of all four ventricles

zonula occludens of the endothelial cells of capillaries

• water
• gasses
• glucose

• Pineal Gland
• posterior lobe of the pituitary gland
• wall ofthe optic recess
• vascular area postrema

• releases hormones into the bloodstream based upon blood chemistry
• releases hormones into the third ventricle that diffuse to the optic recess area

• in the medulla oblongata, on the floor of the fourth ventricle
• vomiting

clear and colorless

• meningitis
• blood-barrier breaks down
• proteins and macromolecules enter CSF causing cloudy appearance

• protection
• supportive
• hormone carrying
• remove neuronal biproducts

• zonula occludens between the ependymal cells of the choroid plexi capillaries that line the ventricles
• water can be actively transported into CSF using ATP

60-150 mm H₂O

UNKNOWN

• increased cranial pressure
• swollen optic disc
• no tumor in imaging

fat, fertile females

heavy duty diuretics

• ventricles
• subarachnoid space
• dural venous sinuses
• venous blood supply

• passive, pressure dependant
• only happens of CSF pressure is greater than blood pressure

superior sagittal sinus

• purely afferent
• hearing and balance

internal acoustic meatus

• spiral organ of Corti
• spiral ganglion (no synapses)
• cochlear nerve
• travels through internal acoustic meatus
• travels in cranial fossa (joins vestibular nerve here)
• enters brain at pontine-medullary junction
• anterior or posterior cochlear nuclei
• end on synapses going to thalamus

• some go directly to thalamus
• Others: inferior colliculus then thalamus
• from thalamus to auditory cortex of temporal lobe

• ampullae of the semi-circular canals
• maculae of the utricle and saccule by hair cells

• hair cell neurons of the vestibule
• vestibular ganglion (no synapses)
• vestibular nerve
• enters at internal acoustic meatus
• enter brain at pontine-medullary junction
• vestibular nuclei of pons and medulla (lateral, medial, superior, and infereior)

• the cerebellum
• spinal cord
• medial longitudinal fasciculus (MLF) (CN III, IV, & VI)
• thalamus
• post-central gyrus

efferent and afferent

• parasympathetic to parotid gland
• somatic to stylo-pharyngeus

• somatosensory and taste from posterior 1/3 of tongue
• sensory from middle ear cavity and pharynx
• visceral sensory from carotid body and sinus

jugular foramen

soma of the nucleus ambiguous of medulla

• CN IX (glossopharyngeal)
• active in swallowing

• arise from inferior salivatory nucleus of medulla
• join with glossopharyngeal nerve
• exit jugular formen then branch off
• travel through tympanic nerve to reenter skull
• form lesser petrosal nerve
• otic ganglion (synapses)
• post-otic-ganglions innervate parotid gland

solitary tract nucleus

the three trigeminal nuclei of brainstem

• principal sensory nucleus
• mesenchephalic nucleus
• spinal nucleus

• to the trigeminal nuclei
• via tympanic plexus, tympanic nerve, then CN IX (glossopharyngeal)

• through CN IX (glossopharyngeal) to solitary tract nucleus of medulla
• some continue on to dorsal nucleus of the vagus nerve

baroreceptive

chemoreceptive

sensory and motor

jugular foramen

• pharynx
• palate
• larynx
• upper esophagus

nucleus ambiguus of hte medulla

dorsal nucleus of the vagus nerve in the infero-posterior medulla

• heart
• bronchi
• esophagus
• liver
• kidneys
• pancreas
• digestive tract

the organ walls

esophageal opening

• general and visceral sensation from all innervated structures
• external ear (via auricular branch)

• superior sensory ganglia
• inferior sensory (nodose) ganglia
• sensory neuronal somae are found here

trigeminal nuclei

• very little from epiglottis taste buds
• these project to the solitary tract nucleus

purely somatic efferent!

• Cranial root
• Spinal root

• muscles of pharynx
• larynx
• palate

• sternocleidomastoid
• trapezius

• spinal root enters skull via foramen magnum
• both spinal and cranial roots exit skull via jugular foramen

nucleus ambiguus

cervical spinal cord in form of rootlets

purely motor (somatic) efferent

• intrinsic muscles of the tongue
• extrinsic musles of the tongue

hypoglossal foramen

• somae of hypoglossal nucleus of the medulla
• exit from anterior medulla

fibers from cervical plexus

sulcus

gyrus (plural gyri)

longitudinal cerebral fissure

vision decussates in optic chiasm and never travels in the corpus callosum

• Central sulcus
• Lateral sulcus/ Sylvian Fissure
• temporal/ parietal division
• temporal/ parietal/ occipital division

• frontal from parietal lobe
• sits between precentral and postcentral gyri

frontal lobe from temporal lobe

insula lobe

• the lateral sulcus/ Sylvian Fissure
• draw a line from where this ends till the occipital lobe
• everything beneath is temporal lobe
• everything above it and behind central sulcus is parietal lobe

vertical line going from pareitaloccipital sulcus (on superior posterior part of cerebrum) to preoccipital notch (located on inferior border of cerebrum)

• it is a medial sulcus of the cerebrum only visible from a midsaggital view
• it divides the frontal and parietal lobes from the Limbic lobe

• an imaginary line from the edge of the central sulcus to the cingulated sulcus
• everything behind line is parietal lobe
• everything anterior is frontal lobe

parietaloccipital sulcus

smell, because it feeds directly into limbic area

• precentral gyrus
• superior gyrus
• middle gyrus
• inferior gyrus
• orbital gyri
• cranial nerve 1/ olfactory bulb

• superior frontal sulcus (divides superior and middle gyri)
• inferior frontal sulcus (divides middle and inferior gyri)

• primary motor cortex
• secondary motor cortex
• premotor cortex
• prefrontal cortex

precentral gyrus

anterior to the precentral gyrus

• anterior to secondary motor cortex
• parts in the superior, middle, and inferior gyri

premotor cortex

most anterior part of frontal lobe

inhibitory control of behavior

• removal of prefrontal cortex
• pituitary adenoma

• detecting sensory information
• integration of information through association areas

• postcentral gyrus
• inferior parietal lobule
• superior parietal lobule

• supramarginal gyrus (lies on margin of lateral fissure)
• angular gyrus (most posterior area)

• precuneus
• located directly anterior to cuneus
• separated by parietaloccipital sulcus

calcarine sulcus of the occipital lobe

• cuneus
• calcarine sulcus
• lingual gyrus
• 2 occipitotemporal gyri (mostly in temporal lobe)

• superior temporal
• middle temporal
• inferior temporal
• lateral occipitotemporal
• medial occipitotemporal
• lingual
• uncas

• superior temporal
• inferior temporal
• occipitotemporal

uncus drops down into tentorial notch from a spinal tap

• higher order visual processes
• auditory and olfactory cortices located here
• anterior tip has part of prefrontal cortex (behavior control)

cingulate gyrus

• emotions
• memory function
• autonomic nervous system

surface of grey matter of the brain

• bottom of sulcus
• top of gyrus

• afferent neurons
• efferent neurons
• interneuron neurons

• they can exist both ways
• linked by horizontal granular cells

Golgi type I

pyramidal cells

• the largest of any type of pyramidal cell
• found in the motor cortex

• receive a single dendrite from superficial molecular layer of cortex
• receive many dendrites from neighboring neurons
• dendrites are highly spined

• terminate deep in cortex
• leave cortex in white matter of cerebrum

deeper in the cortex

Golgi type II

short axons and many dendrites

• act as interneurons
• excitatory or inhibitory

they refine or focus actions

in superficial cortex

interneurons running parallel to cortex surface

superficial cortex

interneurons

inhibitory

• not in the cortex unless coming from association axon of pyramidal cell
• come from cell bodies located elsewhere

• perpendicular to cortex
• they enter and exit cortex
• they are from pyramidal cell axons

• parallel to the cerebral cortex
• examples are bands of Baillarger in IV and V

• very thick centers of striated cortex fibers in the visual cortex
• they form the stria of Gennari (striate cortex)

bands IV and V because of larger amount of sensory fibers

area of cortex with six distinct layers

• Molecular layer
• External granular layer
• External pyramidal layer
• Internal granular layer
• Ganglionic layer
• Multiform layer

• tangential fibers
• (pyramidal dendrites, stellate and Martinotti axons, horizontal cells)

Molecular layer

• many
• a lot
• don't bother counting...

• stellate cell bodies
• pyramidal cell bodies

they are the primary interneurons of the cerebral cortex

pyramidal cell bodies

• more stellate cell bodies
• band of Baillarger

tangentially oriented (mainly efferent)

• larger pyramidal cell bodies
• stellate cells
• cells of Martinotti
• Betz cells
• inner band of Baillarger

• pyramid cells projecting downward
• cells of MArtinotti
• many axons leaving and entering the cortex

• parts of cortex without obvious 6 layers of organization
• makes up 10% of cortex

• Granular
• Agranular

• layers II (external granular) and IV (internal granular) are well developed
• pyramidal layers are not well developed

receiving information (i.e. vision, hearing, taste, etc.)

• postcentral gyrus
• superior temporal gyrus
• parahippocampal gyrus

Thalamocortical fibers

• well developed pyramidal layers (Ganglionic layer and external pyramidal layer)
• poor developed granular layers

• precentral gyrus
• all other motor function areas of frontal lobe

• no, there are only three layers in typical cerebellar cortex, and they are different from the heterotypical layers of cerebral cortex
• they are likely heterotypical
• they are likely motor

neither, they are identical at birth

age 5-7

90%

they are contralateral (right handed = left brain dominant)

pyramidal neurons

medulla oblongata

• dominant hemisphere
• damage to same parts of non-dominant side would not cause speech problems

non-dominant

non-dominant

non-dominant

granular heterotypical cortex

inverted except for the face (i.e. feet are superior to hands, but eyes are superior to mouth

oral region

most parts with a few exceptions (know the exceptions)

• pharynx
• larynx
• perineum (chode, taint, or whatever)

thalamus, specifically from posterior area

• primary motor cortex
• commissural inputs for cross-talk between hemispheres

higher order sensory cortices (i.e. spinal cord)

on the medial surface of the insula lobe

• pain
• tactile discrimination

• integrates all manner of sensory information
• stereognosis
• reaching of contralateral arm under visual guidance

• discrimination without vision
• recognition of something without seeing it by its shape, texture, touch, etc.

along the walls of the calcarine sulcus of the occipital lobe

granular heterotypical

17!!

Lateral geniculate nucleus (LGN) of the Thalamus via optic radiations

parietal lobe and temporal lobe

• temporal visual field is ipsilateral
• nasal visual field is contralateral

• superior calcarine sulcus wall
• inferior calcarine sulcus wall

• 1/3
• we see very little, but we need more detail

18 and 19

• primary visual area
• pulvinar of the thalamus

discerning what is visually important through movement or object recognition

relating visual information to visual memory, in other words, recognition

• it is a higher level cortical area
• involved with spatial/ visual areas
• helps with overall visual experience

• involved with shape/ color perception
• object recognition (especially face recognition)

superior temporal gyrus

granular heterotypical cortex

• isofrequency stripes
• posterior stripes are for higher frequencies

medial geniculate nucleus of the thalamus

• organ of Corti
• cochlear nucleus
• brainstem
• inferior colliculus of midbrain
• medial geniculate nucleus (MGN)
• primary auditory cortex

bilateral

superior temporal gyrus and lateral sulcus

• afferent fibers from primary auditory area
• thalamus

• interpret sounds
• associate sounds with other senses
• especially correlates sound and eye movement

• precentral gyrus
• paracentral lobule (on medial side of cerebrum)

agranular heterotypical cortex

neural fibers that travel from cortex to the spine

neural fibers that travel from cortex to nuclei of brainstem

• corticospinal (to spine)
• corticobulbar (to nuclei of midbrain)

• sensory cortex
• commissural fibers (from other primary motor cortex)
• cerebellum
• premotor cortex
• thalamus
• basal nuclei

• mostly contralateral muscles
• some bilateral muscles

• extraocular
• tongue
• mandible
• upper face
• larynx
• pharynx

• anterior precentral gyrus
• posterior portions of:
• superior frontal gyrus
• middle ""
• inferior ""

six times

controls motor activity patterns

medial surface of the middle frontal gyrus

• motor planning from internal cues and preprogrammed motor movements
• "General of motor cortices if primary motor cortex is foot soldier"

• Prefrontal cortex
• Anterior temporal cortex
• Posterior parietal cortex

• determines personality
• feelings
• initiative
• judgement

• covers most of superior, middle, and inferior frontal gyri
• orbital gyri
• anterior cingulat gyrus

• cerebral cortex
• thalamus
• hypothalamus
• corpus striatum

• stores sensory experiences
• recall of objects seen and music heard

• proprioception
• stereognosis

• Frontal eye field
• Occipital ""
• Dorsolateral prefrontal cortex (DLPC)
• Cingulate cortex
• Supplementary eye field
• Broadman's area 22

• precentral gyrus
• middle frontal gyrus

• occipital
• superior colliculus

voluntary scanning eye movements

relexative eye movements when following a moving stimulus

• contralateral occiptal eye field
• superior colliculus
• frontal eye fields

• voluntary suppression of reflex eye movements
• planning voluntary eye movements

• assess valence of visual targets
• decision making of what is important or noticeable

planning of saccades, especially multiple ones

reflex saccades in response to sounds

superior temporal gyrus

understanding of language and ability to express language

superior temporal gyrus of dominant hemisphere

understanding of written and spoken language

• primary visual cortex
• primary auditory cortex

Broca's area

receptive aphasia (inability to understand spoken word)

• alexia (inability to read)
• agraphia (inability to write)

inferior frontal gyrus of dominant hemisphere

control of muscular movements involved in speech

expressive aphasia (inability to produce speech)

global aphasia (inability to do anything with language)

inferior portion of the postcentral gyrus, along wall of lateral sulcus, and adjoining the insula

facial area of postcentral gyrus

a gray-matter protuberance on the inferior diencephalon that becomes the infundibulum

internal capsule

relay for all sensory systems except olfaction

• internal medullary lamina
• it also carries white matter fibers that connect the different thalamic nuclei

• contains thalamic nuclei
• receive mammilothalamic tract
• project to the cingulate gyrus
• this is the Papez circuit part

• integration of somatic, olfactory, and visceral information
• relates emotions of these senses

houses a number of nuclei (ventral and dorsal)

receive information dealing with motor activity

• the ventral posterior lateral nucleus receives information from the spinal cord, and projects info to the superior part of primary somatosensory cortex
• the ventral posterior medial nucleus receives sensory info from head, and projects info to inferior part of primary somatosensory cortex

• part of the posterior dorsal thalamus
• involved in visual attention (because it is so close to the LGN...)

• optic trac fibers enter here to synapse
• optic radiations leave here to travel to occipital lobe
• it is made up of 6 concentrically arranged layers of cortex

• receives auditory information from both ears (mainly contralateral)
• projects to auditory cortex via auditory radiations

• it is very complicated
• connected to red nucleus, substantia nigra, and corpus striatum

• habenular nucleus
• hagenular commissure
• pineal gland

center for olfactory, visceral, and somatic afferent integration

decussate fibers from thalamus to go to contralateral habenular nucleus

endocrine gland that influences the entire endocrine system

• pineal stalk
• this contains habenular and posterior commissures

• endocrine cells of the pineal gland that secrete inhibitory substances
• melatonin is good example hormone

• they are connected through the LGN of the thalamus
• dark and light cycles affect amount of substances secreted

gray matter

• nerves
• bloodstream
• CSF

pretty much everywhere in order to maintain homeostasis

efferent, but not classified as pre- or postganglionic because they stay within the CNS

• nervous connections (infundibulum)
• blood connections (hypothalamic-hypophyseal portal system)

• caused by a lesion in the hypothalamus
• causes a hormonal imbalance which leads to increased urniation = increased water intake
• has NOTHING to do with blood sugar!

superior colliculi

inferior colliculi

• part of the lateral surface of the midbrain
• connects superior colliculi with lateral geniculate nucleus (LGN) and optic tract

connects inferior colliculi with medial geniculate nucleus (MGN)

anterior portion of midbrain

• internal, most posterior portion of midbrain
• contains corpora quadrigemina and pretectal nuclei
• located poserior to cerebral aquaduct

periaqueductal gray matter of the midbrain

substantia nigra

• controlling movement
• receives afferents from cerebral cortex, cerebellum, lentiform nucleus, substantia nigra, and spinal cord
• rubrospinal tract connects red nucleus to the spinal cord

connects cerebral cortex with the spinal cord, pons, cerebellum, and cranial nerve nuclei