CNS Anatomy Flashcards
What is the basal ganglia?
A region of the base of the brain consisting of 3 clusters of neurons
What is the more accurate name for the basal ganglia?
Basal nuclei
Collection of subcortical cell bodies inside the nervous system
What are the input nuclei of the basal ganglia?
Caudate nucleus
Putamen
What are the intrinsic nuclei of the basal ganglia?
External globus pallidus
Subthalamic nucleus
Pars compacta of substantia nigra
What are the output nuclei of the basal ganglia?
Internal globus pallidus
Pars reticulata of the substantia nigra
Where is the caudate nucleus located?
Collection of grey matter on the wall of the lateral ventricles
What is the lentiform nucleus comprised of?
Globus Pallidus
Putamen
What is the function of the basal ganglia?
Provide a feedback mechanism to the cerebral cortex
What is the arterial supply of the basal ganglia?
Middle cerebral artery
What is the embryological origin of the cerebrum?
Prosencephalon
What separates the 2 cerebral hemispheres?
Falx cerebri (dura mater)
What is the cerebrum located above inferoposteriorly?
Tentorium cerebelli
What is the internal structure of the cerebrum?
Grey matter- forms cerebral cortex
White matter- consists of glial cells and myelinated axons
What is the external structure of the cerebrum?
Sulci (grooves)
Gyri (elevations)
What divides the two hemispheres anatomically?
Median longitudinal fissure
Falx cerebri fills this fissure
What white matter structure connects the two hemispheres?
Corpus callosum
What are the main sulci?
Central sulcus- separates frontal and parietal
Lateral sulcus- separates frontal and parietal from temporal
Lunate sulcus- located in occipital cortex
What are the main gyri?
Precentral gyrus- primary motor cortex
Post central gyrus- primary somatosensory cortex
Superior temporal gyrus- inferior to lateral sulcus, responsible for reception and processing of sound
What are cortical association areas?
Where information from different modalities are collated for processing
What are the association areas of the frontal lobe responsible for?
Higher intellect
Personality
Mood
Social conduct
Language
What are the association areas of the parietal lobe responsible for?
Language- dominant hemisphere
Calculation- dominant hemisphere
Visual spatial functions- non dominant hemisphere
What are the association areas of the temporal lobe responsible for?
Memory
Language
Hearing- primary auditory cortex
What are the association areas of the occipital lobe responsible for?
Vision- primary visual cortex
What is the arterial supply to the cerebrum?
Anterior cerebral arteries- branches of ICAs
Middle cerebral arteries- continuation of ICAs
Posterior cerebral arteries- branches of basilar arteries
What is the venous drainage of the cerebrum?
Network of small cerebral veins
Empty into the Dural venous sinuses
What functions is the cerebellum involved in?
Motor control:
- Coordination
- Precision and timing of movements
- Motor learning
What is the embryological origin of the cerebellum?
Hindbrain divides into metencephalon and myelencephalon
Cerebellum develops from metencephalon division
What separates the cerebellum from the occipital and temporal lobes?
Tentorium cerebelli (tough layer of dura mater)
What separates the cerebellum from the pons?
4th ventricle
What connects the 2 cerebellar hemispheres?
Vermis
What does the cerebellum consist of?
Grey matter- cerebellar cortex
White matter- embedded in the white matter are the 4 cerebellar nuclei
What are the 4 cerebellar nuclei?
Dentate
Emboliform
Globose
Fastigi
What are the anatomical lobes of the cerebellum?
Anterior lobe
Posterior lobe
Flocculonodular lobe
What are the functional divisions of the cerebellum?
Cerebrocerebellum
Spinocerebellum
Vestibulocerebellum
What is the arterial supply of the cerebellum?
Superior cerebellar artery (branch of basilar)
Anterior inferior cerebellar artery (branch of basilar)
Posterior inferior cerebellar artery (branch of vertebral)
What is the venous drainage of the cerebellum?
Superior and inferior cerebellar veins
Drain into superior petrosal, transverse and straight dural venous sinuses
What are the characteristics of the dura mater?
Thick
Tough
Inextensible
What are the 2 connective tissue layers of the Dura Mater?
Periosteal layer
Meningeal layer
Where are the dural venous sinuses located?
Between the 2 layers of the dura mater
What is the vascular supply of the dura mater?
Middle meningeal artery and vein
What is the innervation of the dura mater?
Trigeminal nerve
What are dural reflections?
Meningeal layer folds in on itself
Reflections project into cranial cavity dividing it into several compartments
What are the 4 dural reflections?
Falx cerebri
Tentorium cerebelli
Falx cerbelli
Diaphagma sellae
What are the characteristics of the arachnoid mater?
Thin
Avascular
No innervation
What are the characteristics of the pia mater?
Thin
Tightly adhered to the surface of the brain and spinal cord
Only covering to follow the gyri and fissures of the brain
Highly vascularised
What is the main secretion of the pineal gland?
Melatonin- regulates circadian rhythm of the body
What cells are present in the pineal gland?
Pinealocytes- hormone secreting cells
Glial cells- suppoting cells
What is the anatomical position of the pineal gland?
Located between the 2 cerebral hemispheres
Attached by a stalk to the posterior wall of the 3rd ventricle
In close proximity to the superior colliculi of the midbrain
What is the arterial supply of the pineal gland?
Posterior choroidal arteries (branches of posterior cerebral artery)
What is the venous drainage of the pineal gland?
Internal cerebral veins
What does the pituitary gland secrete?
Hormones that control the action of other endocrine organs and various tissues
What is the anatomical position of the pituitary gland?
Suspended from underside of brain by pituitary stalk (infundibulum)
Sists within sella turcica of the sphenoid bone
What covers the superior surface of the pituitary gland?
Diaphragma sellae
What are the anatomical relations of the pituitary gland?
Anterior- sphenoid sinus
Posterior- posterior intercavernous sinus, dorsum sellae, basilar artery, pons
Superior- diaphragm sellae, optic chiasm
Inferior- sphenoid sinus
Lateral- cavernous sinus
What is the structure of the pituitary gland?
Anterior lobe
Posterior lobe
What is the arterial supply of the pituitary gland?
Anterior lobe- superior hypophyseal artery (branch of ICA)
Posterior lobe- superior hypophyseal artery, infundibular artery, inferior hypophyseal artery
What is the venous drainage of the pituitary gland?
Hypophyseal portal system