System Neuroanatomy Flashcards
Brodmann area 3,1,2
Primary somatosensory cortex
Brodmann area 4
Primary motor cortex
Brodmann area 5 and 7
Somatosensory association cortex
Brodmann area 6
Premotor cortex (PMC) and supplementary motor cortex (SMC)
Brodmann areas 17 and 18
Primary visual cortex V1 (17) and secondary visual cortex V2 (18)
Brodmann areas 41 and 42
Auditory cortex
What does the triune brain model tell us?
The brain is 3 different smaller brains piled on top of each other with conflicting processes
Cranial nerve I
Olfactory nerve: smell
Cranial nerve II
Optic nerve: vision
Cranial nerve III
Opthalamic: eye movement
Cranial nerve IV
Trochlear: eye movement
Cranial nerve V
Trigeminal: face, sinuses, teeth, and jaw muscles (chewing)
Cranial nerve VI
Abducens: eye movement
Cranial nerve VII
Facial: tongue, soft palate, facial muscles, salivary glands, tear glands, taste
Cranial nerve VIII
Vestibulocochlear: hearing and balance
Cranial nerve IX
Glossopharyngeal: throat muscles, taste, gag reflex
Cranial nerve X
Vagus: parasympathetic innervation and gag reflex
Cranial nerve XI
Spinal accessory: neck muscles
Cranial nerve XII
Hypoglossal: tongue muscles
Acronym for knowing whether a nerve is sensory or motor or both
Some Say Marry Money But My Brother Says Big Brains Matter More
Acronym for cranial nerves
- Oh oh oh to touch and feel very good velvet ah heaven
- Olfactory optic oculomotor trochlear trigeminal abducens facial vestibulocochlear glossopharyngeal vagus (spinal) accessory hypoglossal
Coronal plane
Vertical plane
Spinal nerves from top to bottom
Cervical, thoracic, lumbar, sacral, coccyx
Number of each spinal nerve
- Cervical: 8
- Thoracic: 12
- Lumbar: 5
- Sacral: 5
- Coccygeal: 1
What hormone does the parasympathetic nervous system use
Acetylcholine ONLY
What hormone does the sympathetic nervous system use
Preganglionic neurons use acetylcholine, post ganglionic neurons use norepinephrine
Which autonomic NS has longer axons
Parasympathetic axons are longer
What is the organization of neurons in the parasympathetic NS
Most neurons come from the brain stem, while the other few come from sacral sections of the spinal cord
What is medial to the internal capsule
Caudate and the thalamus
What’s lateral to the internal capsule
Putamen and globus pallidus
What two divisions make up the forebrain
Telencephalon and diencephalon
What is the telencephalon made out of
Cortex, basal ganglia, limbic system
What does the diencephalon consist of
Thalamus and hypothalamus
What are the two divisions of the hindbrain
Metencephalon and myelencephalon
What is the metencephalon consist of
Cerebellum and pons
What is the myelencephalon
Medulla
Precentral gyrus
Primary somatosensory cortex
Postcentral gyrus
Primary motor cortex
Tract
Bundle of axons in the CNS
Nerve
Bundle of axons in the PNS
What layer of cortex do pyramidal cells have their cell bodies in
Layers III or IV
Components of the limbic system
Amygdala, mamillary bodies, fornix, hippocampus, cingulate gyrus
Stria terminalis
Provides reciprocal connection between hypothalamus and amygdala
Tectum
Roof of the midbrain
What two structures are present in the midbrain
Colliculi and red nucleus
Purkinje cells
A large type of nerve cell in the middle layer of the cerebellum
Granule cell
A small never cell that makes up the largest and deepest layer of the cerebellum
How are the parallel fibers of the cerebellum made
The axons of the granule cells rise to the surface of the cerebellum to form the molecular layer (outermost layer) of the cerebellum
Association fibers
Connect the cortex to the cortex ipsilaterally
Types of association fibers
Arcuate and uncinate fasciculus, cingulum
Commisural fibers
Connect the cortex to the cortex contralaterally
Projection fibers
Connect the cortex to subcortical structures ipsilaterally
Types of projection tracts
Internal capsule and corona radiata
What role do septal nuclei play in aging
The septal nuclei have a reciprocal connection with the thalamus; loss of septal nuclei is why we lose memory as we age
How do you know you’re looking at the limbic system
When you don’t see the anterior commissure in the sagittal section
Part of the brain supplied by the PCA
- Lateral view: Inferior temporal gyrus and occipital lobe
- Basal view: More caudal, from cerebellum to the optic chiasm
Parts of the brain supplied by MCA
- Lateral view: Superior and middle temporal gyri, and everything but the top parts of the frontal and parietal lobes (everything but the edges of the brain)
- Basal view: Lateral edges of the brain
Parts of the brain supplied by ACA
- Lateral view: top edge of the frontal and parietal lobe
- Basal view: Rostral part of the brain, only the medial part of the brain above the optic chiasm
Draw the circle of Willis
Draw it or visualize!
Difference between ischemic and hemorrhagic stroke
- Ischemic stroke: rupture in an artery causes blood leakage into the brain
- Hemorrhagic stroke: Clots or debris create a blockage of blood in the brain
What role do microglia play in strokes
Microglia cause the swelling of the brain in hemorrhagic strokes
What artery is usually the cause of a stroke
Middle cerebral artery
Angiography
Blood vessels are filled with an X-ray blocking dye (radiopaque) then an X-ray is taken. This provides a detailed view of the cerebral blood vessel
Computerized axial tomography (CT/CAT)
X-ray of different slices of the brain put together
Resolution of CT scans and functional use
- Medium resolution
- Makes it useful for visualizing strokes and tumors
Magnetic resonance imaging (MRI)
Magnetic energy is used to generate images
Resolution of MRI and functional use
- Higher resolution
- Reveals subtle changes in the brain such as the loss of myelin
Diffusion tensor imaging (DTI)
A form of MRI where the diffusion of water in the confined space of axons (fractional anisotropy) is used to produce image of fiber tracts
Fractional anisotropy (FA)
Water tends to diffuse more readily along the long axis of an enclosed space such as an axon
DTI tractography
Using DTI to visualize the orientation and termination of white matter tracts
Function of DTI
Allows us to create a complete map of neural connections in our nervous system
Positron emission tomography (PET)
Radioactive chemicals are injected into the bloodstream and CT scans are taken to map the destination of the chemicals in the brain
Function of PET
Depict the brain’s activity, usually done by administering glucose while subject is performing cognitive tasks
Functional MRI
MRI that detects changes in blood flow
Resolution of fMRI
- High spatial resolution
- Low temporal resolution bc it gathers data over relatively long periods of time to put them together
Function of fMRI
Allows us to see synaptic inputs ad local processing
Optical imaging
Using near-infrared light that passes easily through the scalp and skull
Function of optical imaging
Represent electrical signals of neurons and blood flow
Transcranial magnetic stimulation (TMS)
Stimulation of cortical neurons through application of strong magnetic fields
Magnetoencephalography (MEG)
Ultrasensitive detectors create real-time maps of cortical activity during cognitive processing
Resolution of MEG
- Very high temporal resolution: responds very quickly to moment-by-moment changes in brain activity
What did brain imaging show in someone in a coma?
Researchers asked somebody in a coma to imagine playing tennis, and the corresponding SMA and PMC had shown activity
Brain imaging method with fastest temporal resolution
MEG and EEG: detect very fast changes in the brain
Brain imaging method with slowest temporal resolution
PET
Brain imaging method with lowest spatial resolution
MEG and EEG: not very accurate spatial resolution, don’t provide detailed images
Brain imaging method with highest spatial resolution
MRI/fMRI: provides very fine structural detail in images
6 layers of the neocortex
- Molecular
- External granular
- External pyramidal
- Internal granular
- Internal pyramidal
- Multiform/fusiform
Pyramidal cells
Main output neurons of the cerebral cortex and make up 75% of the cortex
Betz cells
A large pyramidal cell only found in the internal pyramidal layer
Oblique dendrite
Dendrite that branches from an apical dendrite
Fusiform cell
Found in the fusiform layer, and are usually projection cells
Stellate/granular cells
Small cells with processes that project in all planes, found everywhere except the molecular layer of cortex
Horizontal cells of Cajal
Only found in the molecular part of the cortex
Cells of Martinotti
Multipolar neurons that are most densely located within the fusiform layer
Example of afferent (sensory) connection
Special thalamocortical axon
Example of efferent connection
Recurrent collateral?