Introduction to CNS anatomy Flashcards
What 4 things does the central nervous system consist of?
Brain
Spinal cord
Retina
CN II
What are the 2 main cell types of the nervous system?
Neurons
Neuroglia (glial cells)
Which type of nervous system cell is more abundant?
Neuroglial cells
What are the 4 main types of neuroglial cells found in the CNS?
Oligodendrocytes
Astrocytes
Microglia
Ependymal cells
What is the function of oligodendrocytes?
Production of the myelin sheath which surround axons in the CNS
What is the function of astrocytes?
Maintain the blood-brain barrier and control the exchange of chemicals between the circulatory system and nervous tissue
What is the function of microglia?
Proliferate and migrate to site of injury in CNS – carry out phagocytosis
What is the function of ependymal cells?
Line the ventricles and choroid plexus and produce CSF
What are the 2 main types of neuroglial cells found in the PNS?
Satellite cells
Schwann cells
What is the function of satellite cells?
Regulate nutrient and neurotransmitter levels around the neurons and ganglia
What is the function of Schwann cells?
Myelination of axons in the PNS
Which horn of the spinal cord does sensory information enter?
Dorsal horn
Which days does the cranial neuropore and caudal neuropore close in embryonic development?
Cranial neuropore – day 25
Caudal neuropore – day 27
Which pathology can develop if the cranial neuropore does not close?
Anencephaly
Which pathology can develop if the caudal neuropore does not close?
Spina bifida
What are the 3 primary brain vesicles?
Prosencephalon
Mesencephalon
Rhombencephalon
The prosencephalon becomes which 2 secondary brain vesicles?
Telencephalon
Diencephalon
The mesencephalon becomes which secondary brain vesicle?
Mesencephalon
The rhombencephalon becomes which 2 secondary brain vesicles?
Metencephalon
Myelencephalon
The telencephalon becomes which brain structure?
Cerebral hemispheres
The diencephalon becomes which brain structures?
Thalamus and hypothalamus
The mesencephalon becomes which brain structure?
Midbrain
The metencephalon becomes which brain structures?
Pons
Cerebellum
The myelencephalon becomes which brain structure?
Medulla
Which structure connects the right and left hemispheres of the brain?
Corpus callosum
The central sulcus separates which lobes?
Frontal and parietal lobe
Which brain structure is the primary motor cortex?
Pre-central gyrus
Which brain structure is the primary somatosensory cortex?
Post-central gyrus
Which sulcus borders the temporal lobe superiorly?
Lateral sulcus (sylvian fissure)
What is the main sulcus of the occipital lobe?
Calcarine sulcus
Which gyrus surrounds the corpus callosum?
Cingulate gyrus
The left cerebral hemisphere looks after which 3 special functions?
Speech
Writing
Language
The right cerebral hemisphere looks after which 2 special functions?
Spatial perception
Facial recognition
The cortex (grey matter) is made up of what?
Cell bodies
The white matter of the brain is made up of what?
Myelinated axons
Is the corpus callosum grey or white matter?
White
The white matter of the brain is organised into which 2 main structures?
Corona radiata + internal capsule
Define what is meant by a nucleus in the CNS.
A collection of neuronal cell bodies at a point of synapse that share a similar function and projection
The internal capsule sits between which 2 structures?
Thalamus and basal ganglia
Which 3 nuclei constitute the basal ganglia?
Putamen
Caudate
Globus pallidus
Which nuclei combine to form the lentiform nucleus?
Putamen + globus pallidus
Which nuclei combine to form the striatum?
Putamen + caudate
What is prosopagnosia?
Inability to recognise faces
What are the 3 types of fibres found in the brain? What is the function of each one?
Association fibres – connect different areas within the same hemisphere
Commissural fibres – connect corresponding areas in the two hemispheres of the brain
Projection fibres – connect cerebral cortex to brainstem and spinal cord
What is CN I?
Olfactory
What is CN II?
Optic
What is CN III?
Oculomotor
What is CN IV?
Trochlear
What is CN V?
Trigeminal
What is CN VI?
Abducens
What is CN VII?
Facial
What is CN VIII?
Vestibulocochlear
What is CN IX?
Glossopharyngeal
What is CN X?
Vagus
What is CN XI?
Accessory
What is CN XII?
Hypoglossal
Which fibres are found in the cerebral peduncles of the midbrain?
Descending motor fibres of the corticospinal tract
Which CN emerges from between the cerebral peduncles of the midbrain, via the interpeduncular fossa?
Oculomotor
Which structures found on the posterior brainstem are responsible for visual and auditory relay?
Superior + inferior colliculus
Which CN is the only one to arise from the posterior side of the brainstem?
Trochlear
Which muscle and optical pathologies could result from damage to the cerebellum?
Ataxia + nystagmus
What are the 3 lobes of the cerebellum?
Anterior
Posterior
Flocculonodular
Would damage to the cerebellum present with ipsilateral or contralateral symptoms?
Ipsilateral
Which areas of the cerebellum might be affected by increased intracranial pressure and what could this cause?
Tonsils of the posterior lobe may descend through the foramen magnum and compress the medulla
Blood supply to the brain and brainstem is from which 2 major arteries?
Internal carotid artery
Vertebral artery
What are the 3 meningeal layers?
Dura
Arachnoid mater
Pia mater
What are the layers of the dura?
Periosteal layer
Meningeal layer
What is located between the two layers of the dura?
Dural venous sinus
What is located in the sub-arachnoid space?
CSF
What is the name of the fold of the meningeal layer of dura between the cerebral hemispheres?
Falx cerebri
What is the name of the fold of the meningeal layer of dura between the cerebellar hemispheres?
Falx cerebelli
What is the name of the fold of the meningeal layer of dura between the occipital lobe and cerebellum?
Tentorium cerebelli
What is the function of the diaphragm sellae?
Forms a protective pocket for the pituitary gland
What are the 6 main sinuses of the brain?
Superior sagittal
Inferior sagittal
Straight
Transverse
Sigmoid
Cavernous