What is Grey and White Matter?
- Grey - Neurons
- White - Neuroglia (supporting structure), connects Grey Matter areas, largest being the Corpus Callosum
What are Astrocytes?
- Anchor to capillaries
- Regulate chemicals
What are Microglia?
- Immune System of CNS
- Inflammation + Macrophages
What are Ependymal Cells?
- Line brain/spine cavities
- Cilia 'sweep' CSF
What are Oligodendrocites?
- In white matter- Myelin Sheaths
- In grey matter- buffer electrolytes
What are Neurons?
- Grey Matter
- 100 billion
- Form synapses
- Grouped in functional areas
What embryological structure is the brain formed from?
The Neural Tube
What are the Ventricles in the brain?
- 4th inferior connects subarachnoid space
- Continuous with one another and central canal of spinal cord
- Filled with CSF
What protects the brain?
- Mechanical - Cranium, meninges, CSF, BBB
- Chemical - Electrolytes, nutrients, glucose, O2
What is the outermost meningeal layer and its role?
- Dura Mater
- Forms Dural sinuses, collecting venous blood
What is the middle Meningeal layer and its role?
- Arachnoid Membrane
- Loose brain covering
- Sub Arachnoid space w/CSF, blood vessels and attachments to Pia Mater
What is the innermost meningeal layer and its role?
- Pia Mater
- Tightly clings to brain
- Rich in blood vessels
What is Cerebrospinal Fluid and its role?
- Nutritious and oxygenated
- High turn over
- Formed in Choroid Plexuses via Ependymal cells
What is the Falx Cerebri?
- Saggital Fold in Dura Mater
- Limits Brain movement
What is Tentorium Cerebelli?
- Inferior Transverse fold in Dura Mater
- Divides Brain into fore and hind
- Isolates Cerebellum (intratentorial)
What is the basic supply route of blood to the Forebrain?
- Internal Carotid to either
- Anterior Cerebral Artery - Wraps around Corpus Callosum
- Middle Cerebral Artery - Frontal, Parietal, Temporal Lobes
- Posterior Cerebral Artery - Midbrain, Thalamus, Optic Lobe, Corpus Callosum
What is the basic supply route of blood to the Hindbrain?
- Vertebral Arteries through Foramen Magnum
- Supplies Pons, Cerebellum, Middle ear
What is the basic Venous return route?
- Drains to Venous Plexuses and Dural Sinuses to Internal Jugular
- Superficial Veins drain into Cerebral Cortex and form Great Cerebreal Vein
What is the purpose of Sulci and Gyri?
To increase the surface area of the brain
Where are the Motor Areas located?
- Primary on Posterior Frontal Lobe (Somatic)
- Premotor Anterior to Primary (Habits)
- Frontal Eye Field Anterior Premotor (Eyes)
- Broca's Area Anterior to Premotor (Mouth/Speech)
Where are the General Sensory Areas?
- Primary Somatosensory - Posterior Primary Motor Cortex (Spacial Discrimination)
- Somatosensory Association - Posterior Primary SS (Temperature, Pressure, 'understanding')
Where are the Visual Areas?
- Primary Visual - most posterior Occipital
- Visual Association - Anterior to PS (Colour, movement, form_
Where is the Auditory area?
Located Temporally, signals from cochlear send pitch, rhythm, intensity
Where are the smell, taste and vestibular areas?
- Olfactory Corticies - Frontal and temporal (conscious awareness)
- Gustatory Cortex - Parietal Lobe
- Vestibular Cortex - Deep Temporal
What is the Prefrontal Cortex?
Anterior portion of Frontal lobes, intellect, complex learning, recall and personality