Lecture 3: Brain Flashcards
Dural Innervation branches of trigeminal nerve
Branches of trigeminal nerve
CN V1 => anterior & posterior flax cerebrii+ tentorium cerebelli
CN V2 => anterolateral reflections.
CN V3 => lateral reflections.
Floor of posterior cranial fossa by: C2, C3, hypoglossal and vagus
Dural Innervation
Only meningeal layer to be in innervated by sensory fibres
Innervated by:
- trigeminal
- vagus
- upper cervicals
Also stretch sensitive– causes head aches
Dura mater supplied by which artery?
Middle meningeal artery
Where does dura mater drain to?
Internal jugular vein
Arachnoid mater
Located between dura and pia mater
Is avascular
Not attached to the dura
Subarachnoid space between arachnoid and pia mater is filled with CSF
Folds of arachnoid mater project into venous sinus to form arachnoid villi (granulations)
Arachnoid granulations is where CSF diffuses into the blood stream
Pia mater
Highly vascularised, extremely thin
Hippocampus
Plays a role in behaviour and emotional expression as well as a key role in memory and learning
Thalamus
Receives and processes pre cortical input from all sensory systems EXCEPT olfactory
Hypothalamus
Located lateral to third ventricle
Mammillary bodies
Connected to the hippocampus via the fornix
Projects into the anterior nucleus of the thalamusn
Medial geniculate body
MEDIAL GENICULATE body relays AUDITORY impulses from INFERIOR COLLICULUS to primary auditory cortex.
Lateral geniculate body
LATERAL GENICULATE body relays VISUAL impulses from optic tract to primary visual cortex.
Disturbances of PCA
Occlusion will lead to visual disturbances
Disturbances of MCA
Occlusion will lead to sensorimotor function loss in hands and face
Disturbances of ACA
Occlusion will lead to sensorimotor function loss in e lower limbs and bladder weakness
Ventricles lined with what type of cells?
ependymal cells
ependymal cells forming the choroid plexuses that produce and secrete?
cerebrospinal fluid (CSF).
Cerebrospinal fluid does what?
CSF removes waste products associated with neuronal activity & gives brain buoyancy to protect it from trauma.
Dural venous sinuses
- Between periosteal and meningeal layers of dura. No valves.
- Contains blood from superficial brain veins.
- Drains to Internal Jugular Vein.
Two layers of dural mater?
• Two layers: periosteal and meningeal layers.
• periosteal = periosteum covering inner surface of calvaria.
Does not extend through foramen magnum.
Arteries of cerebrum
- Anterior cerebral artery (branch of internal carotid artery)
- Middle cerebral artery (branch of internal carotid artery)
- Posterior cerebral artery (terminal branch of basilar artery)
Common site of atherosclerotic narrowing?
Bifurcation of common carotid artery
Internal carotid and vertebral arteries do what kind of circulation?
Internal carotid- anterior circulation
Vertebral arteries- posterior circulation
Post-central gyrus (dark blue) =
primary somatosensory cortex
Nerve cells in this area receive and interpret sensations of pain,
temperature, touch and pressure from contralateral side of body.
Pre-central gyrus (dark pink) =
primary motor cortex.
Large motor nerve cells in this area control voluntary movements on opposite (contralateral) side of body.
Corpus callosum?
commissure between cerebral hemispheres
Septum pellucidum?
stretches between the two to form medial wall of lateral ventricles
What are Gyri?
elevated ridges
What are Sulci?
shallow grooves
What are Fissures?
deep grooves
Fourth ventricle has foramina in it’s roof so CSF can escape into the?
subarachnoid space
Choroid plexus is located where?
Lateral ventricle
