Lab 1 Neuroanatomy Flashcards
Longitudinal fissure
Longitudinal fissure, found in the mid-line, separates the two cerebral hemispheres.
Lateral sulcus
Lateral sulcus, separates temporal lobe from frontal and parietal lobes
Transverse fissure
Transverse fissure, separates cerebellum from the overlying occipital lobes
Central sulcus
Central sulcus, found on the lateral side of the hemispheres, roughly at the midpoint of the longitudinal fissure. Separates parietal and frontal lobes
Main sulcus/sulci that separate/s frontal lobe
Central sulcus, lateral sulcus
Main sulcus/sulci that separate/s parietal lobe
central sulcus
lateral sulcus
parietooccipital sulcus
Main sulcus/sulci that separate/s temporal lobe
lateral sulcus
parietooccipital sulcus
Occipital lobe sulcus/sulci associated
Pareto-occipital sulcus
Insular lobe sulcus/sulci associated
lateral sulcus
Brain stem
The brainstem connects the spinal cord to the cerebrum. The brainstem has three divisions: the midbrain is located superiorly, the pons is in the middle, and the medulla is located inferiorly.
Brain stem order from most superior to inferior
midbrain is located superiorly, the pons is in the middle, and the medulla is located inferiorly.
Neurons vs glia
Neurons conduct electrical information whereas glial cells, regarded as the support cells, aid the neurons in their function
Grey matter
In the cerebrum and cerebellum the outer layer (cortex) of nervous tissue is gray matter, composed primarily of neuronal cell bodies, dendrites and glial cells.
many cell bodies, relatively few myelinated axons
White matter
Deep to this gray matter that composes the cortex (outer layer of the cerebellum), tracts of white matter are found. White matter is composed primarily of axons
few cell bodies, chiefly long range myelinated axons
What makes the white matter white?
Oligodendrocytes insulate many axons within the CNS (Schwann cells in PNS). The result of the oligodendrocyte wrapping its membrane around the axon is the myelin sheath. Myelin is a lipoprotein. Its high fat content makes myelin appear white.
nucleu îs used to represent
In this context, the word nuclei is used to represent a group of neuronal cells. These neurons are specialised to carry out specific functions. Nuclei sit deep within the white matter
Arrangement of grey and white matter in the spinal cord
reverse of the brain therefore grey matter is surrounded by white matter
cervical nerves =
8
thoracic nerves =
12
lumbar nerves =
5
sacral nerves =
5
coccygeal nerves =
1
Why does the cervical and lumbar enlargements develop
for limb movement - upper limb through the cervical and the lower limb through the lumbar enlargement
Enlargements develop due to the increased number of axonal fibres (axons) that enter and exit at the levels of the upper and lower limbs.
Conus medullaris description
tapering caudal extremity of the cord
The conus in the adult extends to the level of the L1-2 vertebral bodies and one or two vertebrae lower in the infant. In the early embryo, however, the segments of the spinal cord are at the same level as the respective vertebrae.
Explain the disparity between the respective cord and the vertebral levels that one sees in the adult?
The bones of the vertebral column grow longer than the spinal cord does. Therefore, the vertebral column is longer than the spinal cord.
spinal column grows faster than the cord
How and why does the caudate equina form?
As the vertebral column is longer than the spinal cord, the spinal nerves that need to exit at the lower points need to travel for a significant length downwards outside of the spinal cord – forming the cauda equina
to reach structures inferior to the end of the spinal cord
Denticulate ligaments
The denticulate ligaments, extending laterally from the whole cord and anchoring it to the dural sac.
made of pia
Filum terminale
The filum terminale, which extends caudally from the tip of the conus and terminates on the dorsal surface of the coccyx
does not contain nerve fibres as it is made up of pia mater
Anterior nerve roots are
motor
posterior nerve roots are
sensory