Neuroanatomy Flashcards
Anterior
Beak.
Towards the front.
Think of a rat. Anterior is towards the rat’s nose.
Posterior
Tail
Think of a rat. Posterior is towards the rat’s tail.
Dorsal
Back
Ventral
Belly/Front
Medial
Middle
Closer to the midline.
Lateral
Structures farther from the midline
Ipsilateral
On the same side of the midline
Contralateral
On the opposite side of the midline
Section
Slice of the brain
Midsaggital
Cut down the midline to split the right and left hemispheres.
Saggital
Cuts parallel to the midsagittal cut.
Horizontal plane
Cuts parallel to the ground.
Coronal cut
Cut perpendicular to the horizontal and sagittal planes.
Superior
Top/upper surface.
Rostral
Anterior for brain areas
Caudal
Tail or away from the head.
Amygdala
Involved in emotion and certain types of learning and memory
Basal ganglia
Motor control.
Lesions in the basal ganglia result in a loss of ability to initiate voluntary movement.
Cerebellum
Important movement control center, patterns movement into memory
Also called the little brain.
Cerebrum
Coordinates all voluntary movements (with help from the cerebellum Learning and memory Sensation Perception Olfaction Language and communication
Frontal lobe
Responsible for voluntary movement, expressive language, and managing higher-level executive functions.
Also controls some motor functions too on the rostral side of the central sulcus.
Parietal lobe
Sensory perception and integration; some touch sensor
Temporal lobe
Processing auditory information and with the encoding of memory. Separated by the parietal lobe by the lateral sulcus.
Gryri
Bumps that increase the surface area of the cerebral hemispheres
Sulci
Grooves that increase the surface area of the cerebral cortex and form brain divisions
Corpus callosum
Ensures both sides of the brain communicate and send signals to each other
Cranial nerves
There are 12 cranial nerves. Help a person see, smell and hear
Hippocampus
Learning and memory
Named after a seahorse.
Hypothalamus
Energy balance, growth, development, reproduction.
Master switch for hormones and visceral PNS.
Medulla oblongata
Transmitting signals between spinal cord and higher parts of the brain.
Auditory information comes through the medulla.
These cells in the medulla are called the cochlear nuclei.
Damage to these cells results in deafness.
This information heads to the inferior colliculus of the midbrain.
Touch
Taste
Sends information from the spinal cord to the thalamus.
Motor neurons in the medulla control the tongue via cranial nerve XII.
What is the meninges’ purpose?
Protect the brain and spinal cord.
Keep the brain moist.
Dura mater
Surrounds and supports the large venous channels carrying blood from the brain toward the heart (thickest layer meninge)
Arachnoid membrane
Spidery menginge that helps protect the brain and spinal cord from sudden impact. CSF fills the subarachnoid space.
Pia mater
Acts as a barrier and holds in CSF.
Midbrain
Motor movement, particularly movement of the eye, and in auditory and visual processing
Inferior colliculus
Signal integration, frequency recognition, and pitch discrimination
Superior colliculus
Visual, auditory and somatosensory information
Cerebral peduncle
Inferior part of the midbrain.
Assists in refining motor movements, learning new motor skills
Olfactory bulb
Receives neural input about odors detected by cells in the nasal cavity
Optic chiasm
Crucial to vision
Optic nerve
Allows for vision.
Carries information from the retina to the thalamus for visual processing and to the brainstem for reflex processing.
Pineal body
Controls melatonin. Helps regulates sleep cycles. Prevents jet lag. Helps provide restful deep sleep.. Contains a complete map of the visual field.
Pituitary
Controlled by the hypothalamus to release hormones.
Controls stress, growth, and reproduction.
Pons
Relays sensory information to the cerebellum.
Connects the forebrain to the hindbrain.
Regulates breathing.
Involved in control of sleep cycles.
Spinal cord
Afferent and efferent neurons that lead to the PNS and come from the CNS.
The spinal cord is the brain’s connection to the body.
Thalamus
Relay center for sensory pathways before they head to the cortex.
Called the gateway to the cerebral cortex.
Ventricles
Transport CSF for brain support and protection.
What types of neurons does the dorsal root of the spinal cord carry?
Afferent neurons.
What kind of neurons does the ventral root of the spinal cord carry?
Efferent neurons.
What is the somatic PNS?
The PNS under voluntary controls.
Controls the skin and skeletal muscles.
What is another name for the visceral PNS?
Autonomic nervous system.
What brain structure is the master switch for the visceral PNS?
Hypothalamus.
What are the 4 F’s (main functions) of the autonomic nervous system?
Feed
Fight
Flee
“Mate”
What are afferent neurons?
Carry information to the brain.
Think ‘a’ as in approach.
What are efferent neurons?
Carry information from the brain.
Think ‘e’ as in exit.
What is the subarachnoid space?
Not a meninge, but a fluid-filled space between the arachnoid mater and pia mater.
What does the visceral PNS control?
Smooth muscles. Digestive system. Only works well when you are relaxed. Inside of blood vessels. Cardiac muscle. Glands Hormones Pancreas Pineal gland
What is the difference between the sympathetic and parasympathetic visceral PNS?
Sympathetic is fight or flight while parasympathetic is rest and digest.
What is orthostatic intolerance?
Your autonomic nervous system does not work properly and cannot tolerate changes to the body’s position well.
Ex: Not enough blood gets to the brain when the person stands up.
What is POTS?
This is long-term orthostatic intolerance. The tachycardic part means the heart beats really fast when the body changes position (ex: stand up) but it still doesn’t solve the problem.
What is neurocardiogenic syncope?
Fainting.
Syncope=being offbeat.
The head and the heart are not synced.
What is a vasovagal reaction?
A reaction involving the vagal nerve and the heart.
What are the advantages of having a protective hard case around nervous tissue?
Protects it from outside threats (ex: bacteria) and damage.
What are the disadvantages to having a protective hard case around nervous tissue?
It is inflexible so it cannot move to provide more room for ‘extra’ stuff such as swelling, bleeding, or tumors.
It is hard so if the brain hits it hard from the inside, the brain can be damaged.
What is meningitis?
Swelling of the menginges.
Typically caused by bacteria or viruses.
Leads to stiffness and headache.
Diagnosed by a spinal tap (for immune factors) and blood work.
Treated by antibiotics or antivirals.
Prevented by vaccination.
How is the blood-brain barrier protective?
It is tighter security about what can get through the brain.
Gases can still pass easily andd glucose can pass with facilitated transport but amino acids must be transported by active transport.
Tighter junctions between endothelial cells and this picker transport lead to the protective blood-brain barrier.
Why do some circumventral areas like the pituitary, pineal gland, and area postrema not have a blood-brain barrier?
They must be on the pulse of the blood and deliver materials directly to the blood.
What happens in De Vivo disease?
In De Vivo disease where less glucose gets to the brain, there is constant fatigue, motor problems, and developmental problems which can lead to things like learning disabilities because the brain is on constant low power mode.
What is the choroid plexus?
Tissues in the lateral ventricles that make CSF.
What is hydrocephalus?
Swelling of ventricles because CSF can’t get to the subarachnoid space.
Can happen due to physical damage or developmental problems.
What is the difference between grey matter and white matter?
White matter is axons while the grey matter is cell bodies.
What is a nucleus in the brain?
A clearly distinguishable mass of neurons.
What is a substania?
A group of related neurons in the brain but with much less clear borders than nuclei.
Describe the steps for neural tube formation:
The neural plate of the ectoderm of the fetus folds into the neural groove.
The neural groove folds over into the neural fold.
The neural crest is pieces left behind from the neural groove folding. The neural crest develops into the PNS.
Describe primary and secondary vesicle, and secondary structure formation:
The neural tube develops from anterior to posterior.
The prosencephalon develops first into the secondary vesicles of the telencephalic vesicle and the optic vesicle. The secondary structures that develop are the telencephalon and the diencephalon.
The mesencephalon develops into the midbrain and the rectum and tegmentum.
The rhombencephalon, the hindbrain, develops into the cerebellum, pons, and medulla.
What does the telencephalon develop into?
The cerebral cortex and basal ganglia.
What does the diencephalon develop into?
The hypothalamus and the thalamus.
What part of the rhombencephalon does the medulla differentiate from?
The caudal part.
What part of the rhombencephalon do the pons and cerebellum develop from?
The rostral part.
What is decussation?
Crossing of axons from one side to the other.
Happens in the medullary pyramids.
Explain the structure of the spinal cord.
There are dorsal roots that are afferent neurons and ventral neurons which are efferent neurons.
There are sometimes intermediate neurons in the middle which change some motor outputs when there is additional information from the brain.
What is the difference between the cerebral cortex and neocortex?
The neocortex applies to the entire cortex while the cerebral cortex applies to the top few layers.
What is a connectome?
How neurons connect to each other.
What are the 3 main types of cortex?
Primary sensory areas.
Receives signals from ascending (afferent) sensory pathways.
Secondary sensory areas.
Heavy interconnections with primary sensory areas.
Motor areas.
Receive inputs from the cerebellum and thalamic nuclei relaying information from the basal telencephalon.
Send outputs to motor neurons in the brain stem and spinal cord.
What is good about having a “leakier” blood-brain barrier and what is bad about it?
Good:
Easier transport for drugs that treat different diseases.
Bad:
Easier for bacteria and other pathogens to get inside.
Regulation of the extracellular fluid (particularly Na+ and K+ ions) may become messed up.
What is the function of CSF?
Physical cushioning. Transport for wastes. Homeostatic balance. Carries some nutrients and hormones. Allows for some brain size flexibility. Particularly for blood vessels that expand with each heart pump.
What is BDNF?
Brain-derived neurotrophic factor.
It is a hormone that supports brain growth.
More BDNF is made during exercise.
How is hydrocephalus treated?
Short term:
Relieve pressure by putting a hole in the head to drain CSF.
Long term:
A shunt that lets out CSF in the peritoneal cavity in the stomach.
Why is CSF absorbed by the blood?
To transport wastes out of the brain.
Why are ventricles bigger in some diseases?
The reason why ventricles are bigger in people with certain diseases (ex: schizophrenia) is that other parts of their brain are smaller and the CSF is just filling up the space left behind.
