Neuroanatomy

• The brain has 2 cerebral hemispheres which is separated by the longitudinal fissure
• The cerebrum is the large upper part of the brain
• The 3 meninge tissues covering the brain are

  • Dura mater
  • Arachnoid mater
  • Pia mater
• CSF flows through the network of the ventricles and is reabsorbed
• The ependymal cells lining the ventricles produce the CSF
• Describe the pathway of CSF

  1. Lateral ventricle
  2. through interventricular foramen
  3. Into 3rd ventricle
  4. through cerebral aqueduct
  5. 4th ventricle
  6. Subarachnoid space
• Choriod plexus is the network of vessels and cells on the surface of the ventricles
• The medulla oblongata is the most inferior part of the brain and from the thickening of the spinal cord
• The pons is a bulging brainstem structure superior to the medulla
• The pons relay information between cerebrum and cerebellar e.g sleep, hearing and taste
• The cerebellum has a flat area down the middle known as the vermis
• The midbrain is a small region of gray matter nuclei involved in different motor and sensory functions
• The thalamus and hypothalamus lies superior to the midbrain
• The thalamus is mainly involved in relaying sensory signals
• The main function of the hypothalamus is endocrine functions
• The temporal lobe is responsible for voluntary motions e,g planning
• The parietal lobe is involved in sensory reception
• The temporal lobe is involved in hearing and smell
• The occipital lobe is the visual centre
• The basal nuclei surround the thalamus and are involved in motor control
• The 3 basal nuclei are known as the corpus striatum

  • Caudate nucleus
  • Putamen and globus pallidus (lentiform nucleus)
• Corpus collosum separates the right and left hemisphere and is the largest white matter
• The thalamus and hypothalamus are known collectively as the diencephalon
• Central sulcus separates frontal and parietal lobes
• Lateral fissure separates temporal lobe from both the forntal and parietal lobes
• Parietal-occipital sulcus separates the parietal and occipital lobes
• Continuous cortex under the main lobes is referred to as the limbic lobe
• The lateral ventricles have an anterior horn extending into the frontal lobe and posterior horn extending into the occipital lobe
• The lateral ventricles, sit at either side of the corpus collosum
• The 3rd ventricle is connected to the lateral ventricles by the foramen monro
• The choroid plexus in the ventricle walls produces CSF
• Hydrocephalus is defined as an abnormal collection of cerebrospinal fluid within the ventricles of the brain. 
• Communicating hydrocephalus is when the ventricles are in tact and the arachnoid granulates are impaired
• Non-communicating hydrocephalus is when CSF flow is disrupted within the ventrcles. This is usually the cerebral aqueduct
• The CSF can leave the 4th ventricle from 2 lateral formamina and 1 medial foramen
• There are 3 structures which make up the brainstem

  • Midbrain
  • Pons
  • Medulla
• The Midbrain is split into Tectum (posterior) and Cerebral peduncles
• The tegmentum and crus cerebre are divided by the substantia nigra
• The Tectum contains 4 colliculi (2 x superior and 2 x inferior)
• Inferior to the colliculi of the tectum runs the trochlea nerve