Intro to NeuroAnatomy (units 1-4)

Gyrus

a ridge on the cerebral cortex

Sulcus

valley in the cerebral cortex

Cortical Sheet

the outer, surface covering of cerebral cortex, composed of gray matter (neuron cell bodies)

cerebral coretex

The large folded part of the brain that sits above cerebellum & brainstem, made up of white & gray matter

Cerebellum

the "little brain" at the rear of the brainstem; functions include processing sensory input and coordinating movement output and balance

Anterior

Towards the FRONT of the brain

Posterior

toward the BACK of the brain

Superior

Towards the top of the brain

Inferior

Towards the bottom of the brain

Lateral

The lateral view would show the surface of the cerebral hemisphere under the ears

Medial

The medial view would show the inner surface of a cerebral hemisphere

Dorsal

Towards the top of the brain / towards the back surface of the body in the BRAINSTEM & spinal cord

Ventral

towards the bottom of the brain / towards the BELLY surface of the body in the brainstem and spinal cord

Rostral

towards the front of the brain / towards the TOP surface of the BODY in the brainstem & spinal cord (rostral means "beak"

Caudal

Towards the back of the brain / towards the bottom surface of the body in the brainstem & spinal cord (caudal means tail)

Saggital

a vertical slice of the brain cut down the center. from anterior to posterior, giving a view from left or right

Coronal

A vertical slice of the brain cut from superior or inferior, giving a view from the front or back of the brain

Axial

a horizontal slice of the brain cut from left to right, giving a view from the top or bottom of the brain

Central Nervous System (CNS)

brain and spinal cord

Peripheral Nervous System (PNS)

the sensory and motor neurons that connect the central nervous system (CNS) to the rest of the body. ; composed of peripheral nerves that connect the CNS to the limbs trunk and internal organs

autonomic nervous system (ANS)

a subdivision of the PNS that controls visceral functions; includes parasympathetic & sympathetic nervous systems

cranial nerves

a set of 12 specialized nerves that act as the PNS (motor control and sensory info) to the head and neck

Meninges

three protective membranes / layers of tissue b/w the brain and the skull

Dura Mater

the durable, leathery outer protective layer of the meninges

Arachnoid mater

the spider web-like middle protective layer of the meninges that is filled w/ cerebral spinal fluid

pia mater

the thin, shiny inner protective layer of the meninges that "shrink wraps" the brain

Frontal lobe

the anterior portion of the cerebral cortex, rostral to the parietal lobe and dorsal to the temporal lobe ; involved in EMOTION, COGNITION & EXECUTIVE CONTROL

Parietal Lobe

the superior posterior portion of the cerebral cortex, usperior to occipital & temporal lobes

temporal lobe

inferior portion of cerebral cortex

Occipital lobe

posterior portion, primarily involved in vision processing

central sulcus

separates frontal and parietal lobes, surrounded on each side by motor and sensory cortex

Lateral Fissure

the gap that divides the temporal from the frontal and parietal lobes; a fissure is another name for a large sulcus

parieto-occipital sulcus

The sulcus that divides the parietal & occipital lobes

Pre-occipital notch

the notch that serves as the bottom point of the imaginary dividing line between the temporal and occipital lobes; the top of the parieto-occipital sulcus is the top point

Gray Matter

Outer 'bark' of the cerebral cortex composed of neuronal cell bodies ; this is where computations happen ; much of the cortex cinsists of six layers

White Matter

inner region of the cerebral cortex composed of the axons of the neurons with cell bodies in the gray matter; can be thought of as the 'wiring' connecting different regions of gray matter

Brodmann's Area's

Histologically defined as areas of the brain, grouped by similar cell types. Used to refer to locations in the brain.

Neuron

The basic cell in the brain that processes and transmits information in the form of electrical and chemical signals

Glial Cell

surround neurons in CNS and PNS and provide myelination as well as other support for them; most abundant cell types in CNS; Types differ between CNS and PNS;

CNS: oligrodendrocytes, astrocytes, ependymal cells,microglia,

PNS: satellite cells, Schwann cells.

Astrocytes

Specialized glial cells that out number neurons by over 5 fold, They contiguously tile the entire CNS and are involved in many essential complex functions, including biochemical support of the endothelial cells that form the blood brain barrier, provision of nutrients to the nervous tissue, maintenance of extracellular ion balance, and a role in the repair and scarring process of the brain and spinal cord following traumatic injuries.

Myelin Sheath

a layer of protective tissue wrapped around axons of neurons to hasten the transmission of action potentials

Corpus Callosum

The main connection of white matter that is integral for communication between the two cerebral hemispheres

Lateralization

the tendency of brain functions is the tendency for some neural functions or cognitive processes to be specialized to one side of the brain or the other; The medial longitudinal fissure separates the human brain into two distinct cerebral hemispheres, connected by the corpus callosum. While left/right brain differences are a popular topic of general discussion, the majority of brain functions are NOT clearly lateralized (ie we dont have a creative right brain and a math focused left brain)

Split brain patients

patients who constitute a small subpopulation of epileptic patients who have received the surgical resection of the callosal fibers in an attempt to reduce the spread of epileptic foci b/w the cerebral hemispheres. In their canonical work, Sperry and Gazzaniga discovered that split-brain patients can only respond to stimuli in the right visual field with their right hand and vice versa. This was taken as evidence that severing the corpus callosum causes each hemisphere to gain its own consciousness

Spinal cord

a long thin tubular bundle of nervous tissue and support cells (like glia) that extends from the medulla oblongata in the brainstem to the lumbar region of the vertebral column. The brain and spinal cord together make up the central nervous system (CNS) In contrast to cortex, gray matter is in the inside of the spinal cord (beige butterfly shape in image) and is surrounded by white matter. The spinal cord has 3 major functions: as a conduit for motor information, wich travels down the spinal cord as a conduit for sensory info in the reverse direction and finally as a center for coordinating certain reflexes.

Vertebral Column

bony structure of multiple vertebrae that protects the relatively shorter spina cord. Spinal nerves project through small openings in the vertebral bones

Dorsal root ganglion

The sensory nerves of the peripheral nervous system have their cell bodies in _____. (ganglion menas group ofcell bodies) These cells have projections (like dendrites) that carry information from the peripheral sensory receptors - peripheral nerve - and also projections (axons) that carry info into the spinal cord - dorsal root

Ventral root

Is the motor nerve exiting the spinal cord to innervate muscle fibers

Dorsal horn

At the back of the spinal cord, central grey matter forms two arms, each called a ______. The _____ contain the cell bodies of sensory neurons.

Ventral Horn

Two arms located at the front of the spinal cord, central grey metter are called ventral horns. They contain the cell bodies of motor neurons

Central canal of spinal cord

Is the cerebrospinal fluid-filled space that runs through the spinal cord. The central canal connects to the ventricular system of the brain, from which it receives cerebral spinal fluid and shares the same cellular lining,

Bell-Magendie Law

sensory info enters the dorsal horn of the spinal cord and motor info exits the ventral horn. (Mnemonic: In the door, out the vent, thats how spinal info's sent!!!!)

Fascicle

A bundle of neuronal axons surrounded by connective tisue, a component of a nerve

(Term for laterality) Ipsilateral

Belonging to or occuring on the SAME side of the body/brain

(Term for laterality) Contralateral

relating to or denoting the side of the body/brain opposite to that on which a particular structure or condition occurs

(Term for laterality) Unilateral

affecting only one side of the body/brain (or organ/structure)

(Term for laterality) Bilateral

Affecting both sides of the body/brain

Artery

The ____ are the blood vessels that deliver oxygen-rich blood from the heart to the tissues of the body. Each ____ is a muscular tube lined by smooth tissue called endothelium. The largest ____ is the aorta, the main high-pressure pipeline connected to the heart's left ventricle. The aorta branches into a network of smaller arteries that extend throughout the body. The ______ smaller branches are called arterioles and capillaries

Vein

_____ are blood vessels that carry blood towards the heart. Most veins carry deoxygenated blood from the tissues back to the heart (exceptions are the pulmonary and umbilical ____) _____ are less musuclar than arteries and are often closer to the skin. There are valves inside most ____ to prevent backflow of blood as surroudning muscle contractions squeeze the blood back toward the heart

Capillary

_____ is a small blood vessel from 5-10 micrometers in diameter and having a wall one endothelial cell thick. They are the smallest blood vessels in the body; they convey blood between the arterioles and venules. these microvessels are the site of exchange of many substances with the fluid surrounding them (eg water glucose, oxygen, carbon dioxide, lactic acid) Individual capillaries are part of the capillary bed, an interweaving network of capillaries supplying tissues and organs. The more metabollically active a tissue is, the more capillaries are required to supply nutrients and carry away products of metabolism.

Circle of Willis

A circle of arteries that supply blood to the brain. this arrangement of blood vessels allows for collateral blood flow to the brain

Carotid Artery

A blood vessel that supplies the head and neck with oxygenated blood; There are 2 ______. one on each side, They supply blood to the anterior part of the brain;______ divides in the neck into the internal (supplies circle of willis) and external ( the artery you take a pulse from on the neck) ______ arteries.

vertebral arteries

A blood vessel that runs up the back of the neck. there are 2 _____. one on each side. that join at the base of the skull to for the basilar artery. These vessels supply the posterior part of the brain

basilar artery

The artery that supplies the pons, cerebellum, posterior cerebrum, and inner ear. This vessel is formed by the merging if the vertebral arteries.

Middle cerebral artery

The artery that supplies lateral cerebral cortex and anterior temporal lobes; strokes here can affect face, arm, and language use

Anterior cerebral artery

The arteries that supply oxygen to most of the medial portions of frontal lobes and superior medial parietal lobes; strokes here can affect leg use

Posterior cerebral artery

The artery that supplies the posterior part of the cerebral cortex, including the occipital lobes; strokes here can affect vision

Blood Brain barrier

a filtering mechanism of the capillaries that carry blood to the brain and spinal cord tissue, blocking the passage of certain substances (ie infectious agents, immune cells, some drugs)

Basement Membrane

the ______ is a thin fibrous, extracellular matrix that separtes the lining of an internal or external body surface from the underlying connective tissue. the surface may be epithelium (skin, respiratory tract, gastrointestinal tract, etc) mesothelium (pleural/lung cavity, peritoneal/abdominal cavity, pericardial/heart cavity etc) and endothelium (blood vessels, lymph vessels, etc.)

Endothelial cells / Endothelium

____ refers to cells that line the interior surface of blood vessels and lymphatic vessels, forming an interface between circulating blood or lymph in the lumen (open tube within the blood vessel) and the rest of the vessel wall. It is a thin layer of simple single layered cells called _______. vascular _______ line the entire circulatory system from the heart to the smallest capillaries.

Intercellular cleft

an ____ is a channel between two cells through which molecules may travel and gap junctions and tight junctions may be present

Gap junctions

______ are a specialized intracellular connection between many types of animal cells, They directly connect to the cytoplasm of two cells which allows various molecules ions and electrical impulses to directly pass through a regulated gate between cells

Tight junction

______ are areas where the membranes of two adjacent cells join together to form a barrier. They bind cells together, prevent molecules from passing in between cells, and also help maintain the polarity of cells

Dural venous sinuses (aka dural sinuses, cerebral sinuses or cranial sinuses)

The _____ are venous channels found between the layers of the dura mater in the brain. They receive deoxygenated blood from the cerebral veins, receive cerebral spinal fluid from the subarachnoid space via arachnoid granulations, and mainly empty into the internal jugular vein, which ultimately returns this deoxgenated blood to the heart. Unlike the veins, these sinuses are lined by endothelium but are difference from other veins as they do not have the same set of layers which form their walls and do not contain valves

Dural venous sinus EX. Superior Sagittal Sinus

The ____ is located on the superior border of the falx cerebri, a large crescent-shaped fold of dura mater that descends vertically in the longitudinal fissure between the cerebral hemispheres

Bridging veins

Veins that drain the neural tissue and puncture (bridge) through the dura mater to drain into the venous sinuses. They may tear with trauma and bleed to cause a subdural hematoma. ______ have a higher risk of rupturing from trauma from a fall in patients who suffer alcoholism. Long term alcoholism both weakens the vein vessel walls throughout the body and shrinks the brain, which puts greater stress on the bridging veins specifically

Ventricles

CSF-filled cavities in the brain ; four total (left, right, third, fourth)

Cerebral Spinal Fluid (CSF)

fluid surrounding the brain and spinal cord that cushions the nervous system; fluid is similar to blood plasma

Choroid plexus

The specialized cells lining the ventricles responsible for the creation of CSF

Arachnoid Granulations

The Bubble like portions of the arachnoid mater (middle layer of the meninges) into the raining venous sinus system that are responsible for the removal of CSF from around the brain; CSF is 'recycled' into the blood stream

Lumbar puncture

A method to withdraw CSF for testing from a low part of the spinal column just below the spinal cord

Nissil stain

A histological staining technique that uses basic aniline to dye stain RNA blue and is used to highlight important structural features of neurons. the Nissil substance (rough endoplasmic reticulum) appears dark blue to the staining of ribosomal RNA, giving the cytoplasm a mottled appearance. Staining of cortical layers will show darker staining where cell bodies are more densely packed as RNA will be concentrated in the cell body.

Golgi stain

a histological staining technique that uses silver to visualize nervous tissue under light microscopy. The method was discovered by Camillo Golgi, an Italian physician and scientist, who published the first picture made with the technique in 1873. Golgi's method stains a limited number of cells at random in their entirety. the mechanism by which this happens is still largely unknown. Dendrites as well as the cell soma are clearly stained in brown and black and can be followed in their entire length, which allowed neuroanatomists to track connections between neurons and to make visible the complex networking structure of many parts of the brain and spinal cord

Fluorescent tracers

are a type of dye that are activated by light and can be used to trace neural networks. The tracers can be divided into those for tracing single cells and those for monitoring cell populations. while most fluorescent probes are effective in experiments involving fresh tissue sections and cultured cells, there are special requirements for fixed tissues and in vivo imaging

Dendrite

The branched portion of a neuron which receives inputs from synapses with other cells and sends small depolarizations towards the cell body. ___ receive info from other neurons at sites called synapses. Each dendrite can have thousands of synapses which together form complex circuits that govern brain function

Dendritic Spine

a small membranous protrusion from a neuron's dendrite that typically receives input from a single axon at the synapse. ______ serve as a storage site for synaptic strength and help transmit electrical signals to the neurons cell body. Most spines have a bulbous head (the spine head) and a thin neck that connects the head of the spine to the shaft of the dendrite. The dendrites of a single neuron can contain hundreds to thousands of spines. In addition to spines providing an anatomical substrate for memory storage and synaptic transmission, they may also serve to increase the number of possible contacts between neurons

Synaptic Boutons (Axon terminals)

small swellings that are found at the terminal ends of axons. ___ are typically the sites where synapses with other neurons are found and neurotransmitters are stored here to communicate with other neurons via these synapses

Soma (cell body)

The spherical part of the neuron that contains the nucleus, mitochondria, and other organelles necessary for the cell to survive. The ____ connects to the dendrites, which bring information to the neuron and the axon which sends info to other neurons. Although the term "---" is often used to refer to neurons, it can also refer to other cell types as well, including astrocytes, oligodendrocytes, and microglia

Axon Hillock

a specialized part of the neuron at the base of the axon, where it meets the cell body of the neuron; action potentials are initiated here. A high amount of protein synthesis occurs in this region. Within the ___ materials are sorted as wither items that will enter the axon (like components of the cytoskeletal architecture of the axon, mitochondria, etc) or will remain in the soma. In addition, the axon hillock also has a specialized plasma membrane that contains large numbers of voltage-gated ion channels, since this is most often the site of action potential initiation.

axon

the long cell structure that carries depolarizations (action potentials) away from the cell body of a neuron to the synapse

Microtubule

polymers (group of molecules) of a protein called tubulin that form part of the cytoskeleton and provide structure and shape to the eukaryotic cells. They can grow as long as 50 micrometers and are highly dynamic. ___ have the ability to shift through various formations which is what enables a cell to undergo mitosis or to regulate intracellular transport - like along an axon

Microtubule-associated proteins (MAPs)

specialized proteins along the microtubules in the axons that transport protein-containing vesicles between the soma and the synapses at the axon terminals. Such transport of molecules towards and away from the soma maintains critical cell functions.

Intracellular fluid

the fluid inside a cell membrane

Extracellular fluid

the fluid outside of the cell membrane

Electrical potential

the difference in voltage between the intra and extra cellular fluid; this difference is created by the passive (via diffusion) and active (via pumps) movement of charged ions across the cell membrane. This force acts on an ion to drive the movement of the ion in one or another direction

excitatory postsynaptic potential (EPSP)

The change in membrane voltage of a postsynaptic cell following the influx of positively charged ions into a cell (typically Na+) as a result of the activation of ligand-sensitive channels

inhibitory postsynaptic potential (IPSP)

a temporary hyperpolarization of postsynaptic membrane caused by the flow of negatively charged ions into the postsynaptic cell

Node of Ranvier

The small gaps between myelin sheaths in myelinated axons involved in fast action potential propagation down the axon

Synapse

the region/space which information flows across from one neuron to another neuron; space between neurons can be called the synaptic cleft

Axon terminal

the very end of a branch of a neuron's axon, specialized to release neurotransmitters from vesicles into the synapse in response to an action potential