IC1 Anatomy of the CNS Flashcards
The CNS is comprised of
brain and spinal cord
Where is the brain located in & what are the parts of a brain?
Location
in the cranial cavity, protected by the skull and meninges (layers within skull)
Parts
Forebrain
Midbrain
Hindbrain
The forebrain includes ______
The hindbrain includes ______
Forebrain
Cerebrum (more outside)
Diencephalon (more inside)
Hindbrain
Medulla oblongata
Pons (front of medulla oblongata)
Cerebellum (behind medulla oblongata & pons)
The brainstem 🌷 includes
- Midbrain (very important, is where most neuromodulators/peptide transmitters like dopamine, serotonin are)
- Pons
- Medulla oblongata
What is the importance of the brainstem?
- Holds brain structure up
- Connects brain to spinal cord
Describe the cerebrum
- largest part of the brain
- consists of 2 cerebral hemispheres separated by the longitudinal fissure running through the midline
- responsible for many things including learning, thinking, emotions
What is located on the surface of the cerebrum’s hemispheres
- cerebral cortex, a layer of grey matter
- contains grooves called the gyri & sulci (used to “divide” the brain into different lobes)
What is the difference between grey & white matter?
Grey matter
mostly neuronal cell bodies
White matter
axons coming out of the cell bodies
Name the 4 lobes of the brain
- Frontal
- Parietal
- Occipital
- Parietal
Describe the position of the frontal lobe in relation to the central sulcus & lateral fissure
- Anterior to central sulcus
- Superior to lateral fissure
Describe the position of the parietal lobe in relation to the central sulcus & lateral fissure
- Posterior to central sulcus
- Superior to lateral fissure
Describe the position of the temporal lobe in relation to the fissure
- Inferior to the lateral fissure
Describe the position of the occipital lobe in relation to surrounding fissure & lobes
- Posterior to parietal and temporal lobes
- Separated by parieto-occipital sulcus
What does the diencephalon consist of?
mostly thalamus & hypothalamus
Where is the hypothalamus located?
forms the lower part of the lateral wall and floor of the third ventricle
The midbrain connects the _____ to the _____
forebrain to the hindbrain
What does the midbrain consist of?
Cranial nerves
III
IV
Nuclei associated with
III
IV
V
Visual and auditory pathways
(superior colliculus important for visual information, inferior for auditory)
Fiber tracts
Ascending (spinal cord to brain)
Descending fibers (from brain to motor system)
What does nuclei refer to?
refers to a cluster of neurons ≠ nucleus of a cell
Describe the locations of pons in relation to surrounding structures
- Inferior to midbrain
- Superior to medulla oblongata
What does pons consist of?
Cranial nerves
V, VI, VII, VIII
Nuclei associated with
V
VI
VII
VIII
Fiber tracts
Ascending and descending fibers
Medulla oblongata is the most ______ portion of the brain
inferior
What does medulla oblongata consist of?
Cranial nerves
IX, X, XI, XII
Nuclei associated with
V
IX
X
XI
XII
Cardiovascular and respiratory function (most important, dictates speed of HR, rhythm of breathing)
Fiber tracts
Ascending and descending fibers
Describe the cerebellum & its position of in relation to nearby structures
- consists of a midline (vermis) and 2 hemispheres
- connected to the brainstem
- posterior to the pons and medulla oblongata
Where is the spinal cord located?
- in the vertebral column
- protected by meninges and surrounded by cerebrospinal fluid (CSF)
- central canal (hole throughout spinal cord) is filled w CSF
- continuous with the brain at the foramen magnum of the skull
- and tapers off into the conus medullaris
