neuroanatomy Flashcards
4 Midline structures in the brainstem
Motor pathway, medial lemniscus, Medial longitudinal fasciculus, motor nucleus (3,4,6 or 12; if it is a factor of 12 except 1 or 2, it is midline).
4 lateral structures in brainstem
Spinocerebellar pathway, spinothalamic pathway, sensory nucleus of V, (sympathetic pathway too)
Cranial nerve nuclei in medulla
9, 10, 11, 12. Only 12 is midline.
Cranial nerves in pons
5,6,7,8. Only 6 is medial
Cranial nerves above the pons
1, 2, 3 and 4. (3 and 4 are medial in the midbrain.)
Corpus callosum
Fibre bundle linking hemispheres
Anterior cerebral artery
Supplies medial aspects of sensory and motor cortical areas. Blockage causes paralysis and loss of cutaneous/proprioception of lower limb.
Middle cerebral artery
Supplies lateral and inferior cortical hemispheres; sensory cortex, motor cortex, internal capsule and basal ganglia. Blockage leads to paralysis and loss of cutaneous and proprioceptive sensation. Lower limb likely to be spared.
Posterior cerebral artery
Supplies occipital lobe, including V1.
Choroid plexus
Capillary bed enclosed in pia and ependyma. Found in Lateral ventricles, IIIrd and IVth ventricles.
Vertebral arteries
Supply blood to the basilar artery. give off posterior inferior cerebral and spinal arteries.
Cerebral aqueduct
communicates between IIIrd and IVth ventricles
Mesencephalon
Becomes midbrain
Rhombencephalon
Becomes pons and medulla; cerebellum develops on dorsal surface.
Central sulcus
Divides somatosensory and motor cortex
Lateral sulcus
divides temporal from the frontal and parietal cortex
IIIrd ventricle
associated with the thalamus and hypothalamus
Communication between lateral and IIIrd ventricles
Inter-ventricular foramen
Communication between IIIrd and IVth ventricles
via cerebral aqueduct
CSF in spinal cord
in central canal
Blockage of CSF flow leads to…
hydrocephalus.
CSF enters the subarachnoid space from the IVth ventricle via…
the foramen of Magendie and foramina of Luschka
Cisterna magna
Space between medulla and cerebellum.
Lumbar cistern
Tapped into in a lumbar puncture at level L3/4 or 4/5; between level L2 and upper sacral level.
Basilar artery branches
Anterior inferior cerebellar, pontine arteries and superior cerebellar arteries. Also posterior cerebral arteries
Calcarine sulcus
Medial aspect of occipital lobe; V1 found round this.
Primary visual cortex
Brodmann’s area 17
Primary somatosensory cortex
Brodmann’s 1,2 and 3.
Primary motor cortex
Brodmann’s area 4.
Cerebral angiography
Used to identify thrombosis, aneurysms or vascular blockage caused by tumours.
CAT
Computerised axial tomography; used to investigate tumours, haemorrhage and cerebral atrophy.
Nissl stains
Stain nuclei and cell bodies but not dendrites or axons.
Myelin stain
Used to examine white matter
Golgi stain
Picks out random cells; stains v. dark in entirety
Nociceptive afferents terminate
in dorsal horn
Crossing of nociceptive
Via ventral commissure within spinal cord
First proprioceptive/fine touch synapse
Gracile (lower limb) and cuneate (upper limb) nucleus
Spinothalamic pathway
Nociceptive. Enters spinal cord; synapses in dorsal horn. Crosses spinal cord, ascends contralaterally. Sends branches to reticular formation in medulla. Forms spinothalamic tract in pons - ‘spinal lemniscus’. Spinal lemniscus in midbrain. Synapses in thalamus, projects to cortex
Dorsal column - medial lemniscal pathway
Enters spinal cord; ascends ipsilaterally.. Decussates in medulla; sensory decussation. Ascends in medial lemniscus. Synapses in thalamus, before projecting to the somatosensory cortex.
Interomediolateral nucleus
sympathetic preganglionic neurons; axons to sympathetic chain. Thoracic only.
Clarke’s nucleus
proprioceptive relay cells from lower limb; only present in thoracic and upper lumbar. Roughly at medial side of base of dorsal horn.
Dorsolateral column
Descending motor form cortex
Anterolateral column
Ascending pain/temperature
Dorsal horn
local sensory processin
Ventral horn
Motor neurons
Ventral column
motor descending from brainstem.
Spinal nucleus of V
important for pain and temp of head and neck; prominent in medulla
Motor decussation
Decussation of descending motor fibres at border of medulla and spinal cord.
Sensory decussation in medulla
From gracile and cuneate nuclei to medial lemniscus.
Inferior cerebellar peduncle
sensory info to cerebellum
Cerebral peduncles (midbrain)
Fibres descending from cortex to brainstem and spinal cord.
Tectum in midbrain
Superior and inferior colliculi; dorsal to aqueduct