Neuro

Sympathetic fibers

exit the CNS at the thoracic and lumbar levels

parasympathetic fibers

exit the CNS at the brain stem and sacral levels

A ganglion

Sits in the gap between pre/post fibers, and is a cluster of nerve cells

Sympathetic length

the ganglia sit in a connected chain right next to the spinal cord. This means the preganglionic fibers are very short, and the postganglionic fibers must stretch a long way to reach the organs.

Parasympathetic Length

The preganglionic fibers exit the brain or lower spine and travel a long distance across the body. The ganglia are located right next to, or even inside, the specific target organ. The postganglionic fiber is microscopic and short

tThe lumbar cistern

he largest subarachnoid space in the spinal cord, mostly void of neural structures

A lumbar puncture

To obtain cerebral spinal fluid for testing -

Dorsal Root Ganglion

Houses the cell bodies of afferent sensory fibers, "the bump"

Dorsal Roots

Sensory info enters the spinal cord via this from afferent fibers, the roots by the “Bump” or the Dorsal Root Ganglion

Ventral Roots

Motor info exists the spinal cord via this from efferent fibers

Vertical "Bump"

Cell bodies/ganglia of sympathetic fibers

Gastrulation

the process by which the embryonic germ layers (endoderm, mesoderm , and ectoderm) are formed following blastulation (the formation of a sphere with a fluid-filled cavity)

Endoderm

gives rise to the digestive and respiratory tracts and their related structures

Mesoderm

gives rise to the skeletal system as well as muscles

Ectoderm

gives rise to skin and the nervous system

neurulation

is the process by which the neural plate (the thickened region of dorsal ectoderm) becomes the neural tube

Anencephaly

when the anterior neural tube fails to properly close

Protrusion of the meninges

failure of the distal neural tube to properly close

The prosencephalon or forebrain gives rise to what during neural tube development

the telencephalon (cerebrum) and diencephalon (thalamus and hypothalamus), as well as the optic vesicles (which develop into the eyes)

The mesencephalon, or midbrain

virtually stays the same during neural tube development

The rostral end of the neural tube

differentiates into 3 primary brain vesicles

The rhombencephalon, or hindbrain

gives rise to the metencephalon (pons and cerebellum) and the myelencephalon (medulla)

Gyri

Ridges

Sulci

Grooves that separate the Gyri

Frontal Lobe

Motor Functions

Parietal Lobe

Sensory Functions

Occipital Lobe

Visual Functions

Temporal Lobe

Auditory Functions

Precentral Gyrus

integrating motor functions from different parts of the brain.

Postcentral Gyrus

 integrating sensory functions from different parts of the brain.

Anterior

Toward the front of the body.

Posterior

Toward the back of the body.

Medial

Toward the middle of the body

Lateral

Away from the midline of the body

Rostral

Towards the nose or snout

Caudal

Toward the tail or taildown

Dorsal

Towards the Back or Upper Surface

Ventral

Toward the belly or lower surface

Superior

Towards the head or upper body

Inferior

Towards the feet or lower body

Ipsilateral

Located on the same side of the body

Contralateral

Located on the opposite side of the body

The basal ganglia

composed of several groups of nuclei including the caudate nucleus, putamen, and globus pallidus. Interconnected with the frontal lobe, and associate with control of movement

The limbic system

includes the cingulate gyrus and amygdala and is associated with emotion and learning

Other structures associated with the limbic system

the hippocampus and fornix (memory and learning), the olfactory bulb (smell), and hypothalamus (behaviors like sex and aggression).

The limbic system includes

The cingulate gyrus and amygdala and is associated with emotion and learning.

Other structures associated with the limbic system

the hippocampus and fornix (memory and learning), the olfactory bulb (smell), and hypothalamus (behaviors like sex and aggression).

The Thalamus

 A major relay point for almost all incoming sensory information headed towards the cortices. All info goes from CNS is into thalamus, there’s 1 in each hemisphere

Hippocampus

plays a critical role in learning and memory.

Hypothalamus

composed of several nuclei that control various functions (many of which are critical), including hunger, thirst, and temperature; it also regulates the endocrine system by controlling the pituitary gland

Brain stem is composed of

the midbrain, pons (motor and sensory), and medulla (respiration and heart rate).

The brain stem serves to

relay information to and from the cerebral hemispheres and cerebellum to and from the spinal cord.

The roof (dorsally) of the midbrain

known as the tectum; it is made up of the superior colliculi (vision) and the inferior colliculi (auditory).

The floor (ventrally) of the brain stem

contains the tegmentum and includes the substantia nigra (associated with the basal ganglia), the periaqueductal gray (associated with pain), and part of the reticular formation (neurons associated with sleep and arousal).

The cerebellum

Very convoluted, made of 3 layers, and plays a role in certain aspects of cognition, including learning. Lesions can result in uncoordinated, inaccurate movements

The corpus callosum

a large, thick band of nerve fibers that connects the left and right halves of the brain

Gray matter (spinal cord)

The cell bodies (somas) of motor efferent fibers are located within the ventral horns of gray matter

Gray Mater (Cortex)

Has a darker appearance due to the presence of numerous cell bodies. it’s largely associated with processing information

White Matter Cortex

Tissue just below the cortex is composed of this, it’s tissue that contains a high number of myelinated axons; it appears lighter and it’s largely associated with transmitting information

Matter location Cortex vs Spinal Cord

White is on the outside, Gray on the inside in the Spinal Cord; In the Cortex Gray is on the outside and white is on the inside

Meninges

They serve to protect the delicate brain and spinal cord tissue from the surrounding bone

Meningitis

an inflammation of the meninges due to an infection, usually bacterial or viral in origin.

Meniges Layers

The dura mater (outermost layer — which in areas is attached to bone and is very think), the arachnoid membrane (middle layer), and the pia mater (innermost layer — which adheres to the brain). The subarachnoid space between the arachnoid and pia is filled with cerebrospinal fluid (CSF).

Cerebrospinal spinal fluid (CSF)

produced by the choroid plexus lining the lateral ventricles, circulates throughout the ventricular system, is located in most of the ventricles. will eventually exit the ventricular system and return to systemic circulation (in the subarachnoid space, it is absorbed into the blood via arachnoid villi)

The Ventricular system how does it become what it is

arises from the luminal spaces of the developing neural tube

Hydrocephalus

an accumulation of fluid within the ventricles that typically results in compression of the brain; it can be caused by impaired absorption, altered hydrodynamics, or overproduction of CSF.

Synaptic Vessels

In the axon terminal, and they contain neurotransmitters

Glia Cells

more numerous, but tend to serve a more supportive role

Ventricles

are interconnected for the flow of CSF throughout the brain and spinal cord. These ventricles include two lateral ventricles (in each cerebral hemisphere and temporal lobe), one third ventricle (on the midline between the thalamus of each lobe), and one fourth ventricle (between the brainstem and cerebellum)

Ventrical Connection

The lateral ventricles are connected to the third ventricle via the interventricular foramina. The third ventricle is connected to the fourth ventricle via the cerebral aqueduct.

Input zone (dendrites)

extensions of the soma that receive incoming information

Integration zone (cell body/soma)

the main part of the neuron, housing the nucleus and much of the cellular organelles

Conduction zone (axon)

Long extension that carries information away from the soma towards axon terminals

Output zone (axon terminals/boutons)

housing transmitter(s), the chemical signal or message between neurons and target tissues

Ramon (neural doctrine)

neurons are separated and somehow communicate

Golgi (reticular theory)

Neurons are close together thats how they communicate

A synapse is composed of

presynaptic membrane, a synaptic cleft (in between), and postsynaptic membrane

Neurotransmitters relationship to synapse

are released by the presynaptic neuron, and they bind to receptors on the postsynaptic membrane

Neurotransmitter release

Arrives in the form of an electrical signal- arriving at the axon

terminal

PNS

Nerves, Ganglia, sensory organs, and everything else

Types of Glia cells with functions

Astrocytes: Act to regulate extracellular environment including some neurotransmitters; helps in forming the BBB, often associated with edema.

Microglia: Acts as the immune cells of the brain

Oligodendrocytes: Responsable for myelination in the CNS

Schwann cells: Responsible for myelination in the PNS