The Brain Flashcards
What is contained within the pons?
Pontine nuclei - co-ordination and maximising voluntary motor output
Contains pneumotaxic tract - help control breathing
Origin of CN V, VI, VII, and the vestibular part of VIII
What lobe is highlighted?
Parietal lobe
What is highlighted?
The central sulcus
What area is shown?
Broca’s area - speech (motor)
How do the vertebral arteries reach the brain?
Ascend the neck through foramina in the transverse processes of the cervical vertebrae
Join close to the foramen magnum to form the basilar artery
What are the ventricles of the brain?
Lateral - one in each hemisphere
Cerebral aqueduct - runs through midbrain and connects 3rd and 4th
3rd ventricle - inside the thalamus. connected to lateral ventricles via foramina of Munro
4th ventricle - connects to sub-arachnoid space and central canal of spinal cord
What is the role of the hypothalamus?
Regulates the autonomic nervous system and homeostasis (body temp., thirst etc.)
Produces hormones and is connected to the pituitary gland
What structures make up the diencephalon?
Thalamus
Hypothalamus
Pineal gland
What cranial nerves come from the midbrain?
CN III (occulomotor) CN IV (trochlear)
Where are the dural venous sinuses formed?
Either between the periosteum of the skull and the dura or between 2 layers of dura
What is highlighted?
The pons
What are the layers of the meninges?
Pia matter - innermost
Arachnoid - middle layer
Dura matter - outmost layer
What is the action of the basal ganglia?
Regulated the initiation and termination of body movements.
Also involved in memory, planning and emotional response (via the limbic system)
What is the importance of the central sulcus?
Separates the frontal and parietal lobes
Useful in finding the functional areas of the brain
Motor cortex sits anterior to the sulcus and the sensory cortex sites posteriorly
What lobe is highlighted?
Occipital lobe
What lobe is highlighted?
Frontal lobe
What is the main innervation of the dura?
Trigeminal nerve (CNV)
What is the role of the cerebellum?
Controls sub-concious aspects of skeletal muscle movements and co-ordinates complex sequences
Regulates posture and balance
What is the role of the superior colliculi?
Visual tracking, scanning
What is highlighted?
Longitudinal fissure - separates the cerebral hemispheres
What is the role of the red nuclei of the midbrain?
Co-ordinate muscle movement
Describe the middle meningeal artery?
Comes from the maxillary artery and passes through the foramen spinosum to supply the dura with blood
What is the role of CSF?
Provides mechanical and physical protection to the brain and spinal cord
How to the ICA reach the brain?
Pass into carotid canal and through the cavernous venous sinus
What is the role of the inferior colliculi?
Auditory startle reflex
What is the role of the dural venous sinuses?
Drain blood from the brain and channel it into the internal jugular vein
What recycles the CSF?
Arachnoid granulations - provide a route for CSF back into the blood
What is the choroid plexus?
Clumped together ependymal cells. Hang inside the ventricles.
Found in the lateral, 3rd and 4th ventricles
What is highlighted?
The circle of Willis
Which arteries supply blood to the brain?
Vertebral arteries
Internal carotid arteries
Describe the posterior meningeal artery?
Comes from the occipital artery
Supplies the dura of the posterior fossa
What lobe is highlighted?
Temporal lobe
Where does the substantia nigra lie?
In the midbrain
What is indicated in this image?
The confluence of the sinuses - collects the blood and passes it to the transverse and sigmoid sinuses to be drained into the IJVs
What are association tracts?
Tracts between gyri of the same hemisphere
What is the role of ependymal cells?
Filter blood plasma to make CSF
Through what structure do the 2 cerebral hemispheres communicate with one another?
Corpus Callosum
What are commisural tracts/fibres?
Tracts from one hemisphere to the corresponding region of the other
Describe the sub-arachnoid space?
Lies between the pia and arachnoid matter
Contains CSF
What area is shown?
Wernicke’s area - speech (recognition)
What is the corpus callosum?
White matter tract that connects the cerebral hemispheres
What are projection fibres?
Fibres from the cerebrum to the thalamus, brainstem etc.
How does the cerebellum communicate with other areas of the brain?
Via cerebellar peduncles
Superior cerebellar peduncle - midbrain to cerebellum
Middle - pons to cerebellum
Inferior - medulla to cerebellum
Describe the anterior meningeal artery?
Comes from the ethmoid branches of the internal carotid artery
Supplies the dura of the anterior fossa
What is contained within the lateral fissure?
Middle cerebral artery
What is the clinical relevence of the dural venous sinuses?
Communications exist between cavernous venous sinus, pterygoid venous plexus, the ophthalmic veins and facial veins that allow for the potential spread of bacteria from the superficial veins to the venous sinuses
What surrounds the basal ganglia?
The insula (except for substantia nigra which is in the mid brain)
What is highlighted?
Medulla
What does the midbrain connect?
Connects the pons and medulla to the diencephalon
What covers the pituitary gland?
Sella Turcia
What is highlighted?
The midbrain
What hormones are released by the pituitary gland?
Growth hormone
FSH and LH
What are the folds of the dura that protect the brain?
Falx Cerebri - lies between the cerebral hemispheres and carries the inferior saggital venous sinus
Tentorium Cerebri - covers the cerebellum
What is this structure?
Lateral fissure - between the temporal and parietal/frontal lobes
What is highlighted?
The cerebellum
What is highlighted?
Thalamus
What is highlighted?
Hypothalamus
What is contained within the medulla?
The pyramids (motor tracts)
Cardiovascular centres (rate/force heartbeat, diameter of vessels)
Breathing centres
Nuclei associated with touch, pressure and vibration
Olives - proprioception
Origin of CN IX, X, XI, XII and cochlear part of VIII
What is the role of the pineal gland/epithalamus?
Produces melatonin to regulate body clock
Contains the habenular nucleus (olfaction and emotional response)
What is highlighted?
Pituitary gland
What is the role of the thalamus?
It is a major sensory relay station
Spinal cord, brainstem, midbrain to the thalamus and then to the cerebral hemispheres
Also involved in motor pathways
Has connections to the hypothalamus and limbic system
