A&P Central Nervous System

Will probably add slides about how differing parts of the brain do similar functions.

Cerebrum

Cerebellum

Cerebral hemisphere

Think of the hemispheres like paired bones

Brainstem

Subdural space

Subarachnoid space

Periosteal layer of the dura mater

Miningeal layer of the dura mater

Dura mater

Makes up the fissure between the cerebral hemispheres

Merges at the corpus collosum

Thick enough to project inwards towards the brain and provide support

Arachnoid mater

Follows entire surface of the brain like cling wrap

Pia mater

Follows entire surface of the brain like a coat of paint

Periosteum

Connective tissue layer between the skin of the scalp and the skull

Falx cerebri

Portion of meningeal dura mater that supports the great longitudinal fissure between the two brain hemispheres

Extends from the cranial roof to the corpus collosum

Tentorium cerebri

Portion of the meningeal dura mater that separates the occipital lobe and cerebellum

Supportive structure located at the posterior cerebrum (Where the cerebellum is located)

The cerebrum

largest portion of the brain

Contains five lobes

Consists of L and R hemispheres

Corpus callosum

Connects the two cerebral hemispheres

Transmits messages from one side to the other

Each hemisphere controls the opposite side of the body

Frontal lobe

Motor and executive functions

Front motor of a car

Temporal lobe

Hearing

Tempo (Like in music)

Occipital lobe

Vision

Binoculars

Parietal lobe

Somatosensory information

Pressure, Pain, Position, Proprioception

Limbic lobe of the cerebrum

Name given due to its close proximity to the limbic system, but not a part of it

Emotions & Memory

Love and Learning

How to assess function of the frontal lobe

Spelling backwards and digit span

Cerebral cortex (Neocortex)

The cerebrums surface

Convoluted into hundreds of folds

Where all the higher brain functions take place

Contains ~20% of all neurons

Gray vs. white matter

The outer portion (Gray matter) contains the neuron’s body

The inner portion (White matter) contains axons which are sheathed in myelin, which is white

The cerebellum

10% of total brain weight, but 80% of all neurons in the brain

-Maintains balance

-Coordinating movement

-Vision

-Motor learning

Diencephalon

Contains the thalamus, hypothalamus, epithalamus, subthamalus

Thalamus

Brains “relay station”

Sends sensory signals (Vision, touch, hearing, taste) to the cerebral cortex

Epithalamus

AKA pineal gland

Helps regulate biological rhythms (Like sleep) and produces melatonin

Hypothalamus

The “control center” for homeostasis

Regulates: Temperature, hunger, thirst, sleep, and hormones

Subthalamus

Involved in movement control

Limbic Lobe

Located deep in the brain

Center of our emotions, learning, and memory

Contains cingulate gyri, amygdala, hypothalamus, hippocampus

Amygdyla

Emotional reactions

Hippocampus

Memory

Hypothalamus

Homeostasis

Cingulate gyri

Emotional and behavior

Ventricles

Hollow fluid-filled cavities

The ventricles contain the choroid plexus which creates CSF

Choroid plexus

Produces cerebrospinal fluid (CSF)

Maintains pressure in the brain

Cushions brain to prevent injury

Ventricular system

Two lateral ventricles

Foramen of Monro

Third ventricle

Aqueduct of Sylvius

Lateral Horns

End in subarachnoid space

Central horn (connects inside spinal cord)

Fourth ventricle

Cycle of CSF

Lateral ventricles → Foramen of monro →Third ventricle → Aqueduct of sylvius → Fourth ventricle → Lateral horns + Central horn → Subarachnoid space (Brain and spine) → Arachnoid granulations (Absorb and recycle CSF) → Superior sagitall sinus → Jugular veins

Places where CSF flow can become obstructed

Foramen of monro

Aqueduct of sylvius

Obex

Lateral ventricles

Foramen of monro

Third ventricle

Aqueduct of sylvius

Fourth ventricle

Cisterna magna

Subarachnoid space

Central canal

CSF recycling

Absorbed by arachnoid villi (granulations) into the superior sagittal sinus

Works it way through the transverse sinus → sigmoid sinus → Jugular veins

Balance is maintained by the CSF absorbed and the amount produced

Superior sagital sinus

Choroid plexus

Arachnoid granulation

Subarachnoid space

Meningeal dura mater

Hydrocephelus

Enlargement of the ventricles due to blockage of CSF cycling

Syringomyelia

Collection of CSF in the spinal cord

Midbrain

Produces dopamine

Pons

Stimulation of breathing and controlling sleep cycles

Medulla oblongata

Controls respiration, the cardiovascular system, consciousness

_{Really, all of the unimportant things}

The brain stem

Connects narrow spinal cord with the forebrain

Spinal cord

Connects brain and peripheral nervous system

Suspended in vertebral canal, protected by vertebrae

Surrounded by meninges and CSF

45cm long in adults

Transmission of neural signals between the brain and body

Vertebral body

Neuroforamen

Hard to tell from other picture, but its a foramen where the neurons come out of 

The vertebrae (arch)

Bones of complex anatomy

Intervertebral disks

Provide shock absorption

Conus medullaris

The tapered, inferior end of the the spinal cord

From here the spinal cord turns into strings called caude equina

Filum terminale

Non-neural cord

Connects the spinal cord to the coccyx

“End” of the spinal cord

Order of spinal nerves superior to inferior

Cervical, thoracic, lumbar, sacral, coccygeal

Number of cervical spinal nerves

8

Number of thoracic spinal nerves

12

Number of lumbar spinal nerves

5

Number of sacral spinal nerves

5

Number of coccygeal spinal nerves

1

Cervical enlargement

Where spinal cord enlarges to supply the upper limbs

Between the C4 to T2 vertebrae

Lumbar enlargement

Where spinal cord enlarges to supply the lower limbs

Between the L2 to S3 vertebrae

White and grey matter of the spine

Cell bodies are located in the middle of the spinal cord (Gray matter)

Myelinated axons protrude out of the spinal cord (White matter)

Dorsal median sulcus

White matter

Dorsal horn of gray matter

Lateral horn of gray matter

Ventral horn of gray matter

Ventral median fissure

The central canal

Center of the spinal cord

Lined with ependymal cells

Contains CSF, protects the spine

Helps transport nutrients and waste

4th ventricle → Conus medullaris

Ganglion

A group of neurons (Cell bodies) outside the CNS

Nucleus

A group of neurons (Cell bodies) within the CNS

Nerve

A group of nerve fibers (axons) outside the CNS

Tract

A group of nerve fibers (axons) within the CNS