2024 Brain and Cranial Nerves PDF

Gross Anatomy of the Brain & Cranial Nerves Gross Anatomy of the Brain Brain Development https://www.youtube.com/watch?v=yxFYN9gF_EQ Neural stem cells differentiate into neurons & glial cells forming neural tube. 3-4 wks 4-5 wks 7 wks 9 months  CNS Prote...

Gross Anatomy of the Brain & Cranial Nerves Gross Anatomy of the Brain Brain Development https://www.youtube.com/watch?v=yxFYN9gF_EQ Neural stem cells differentiate into neurons & glial cells forming neural tube. 3-4 wks 4-5 wks 7 wks 9 months  CNS Protection Meninges of the Brain Protective barrier of brain and spinal cord Dura matter connects brain & spinal cord to skull and vertebral column Arachnoid matter loosely covers brain - route of blood vessels/nerves/ cerebrospinal fluid collagen fibers span subarachnoid space (filled with cerebral spinal fluid) to connect to pia matter Pia matter Rich blood supply (nutrients) Closely envelops the brain, runs deep into fissures Meninges Four Major Parts of the Brain (Not responsible for the Sheep brain content just used as learning tool) 1. Cerebrum (Cerebral hemispheres) 2. Brain stem (midbrain, pons, and medulla oblongata) 3. Diencephalon (thalamus, hypothalamus & pineal gland) 4. Cerebellum Cerebrum  Cerebrum Most superior portion of the brain Consists of L & R cerebral hemispheres Each has cerebral cortex (outer layer of grey matter) & inner layer of white matter Separated by longitudinal fissure Surface has ridges/grooves (gyri & sulci) Gyri & Sulci http://www.hhmi.org/biointeractive/development-human-embryonic-brain Structures of the Cerebral Cortex Functional Areas of the Cerebral Cortex Connection between L & R Hemispheres Corpus Callosum connects two sides Largest bundle of nerve fibers (~200 mill) Brain Stem Brainstem Midbrain Sheep Brain Brainstem Midbrain Corpora quadrigemina 4 rounded elevations: 2 superior (visual) Sheep Brain & 2 inferior (auditory) Cerebral aqueduct (channel that allows CSF to flow between ventricles Fxn: movements of the eye, visual & auditory processing, pain and sleep Associated with cranial nerves III & IV Brainstem Pons Primarily associated with sleep Sheep Brain Contains the nucleus of the pontine respiratory center Associated with 4 pairs of cranial nerves (V, VI, VII & VIII)  Brainstem Medulla oblangata Passes messages between spinal cord & brain Contains the cardiovascular center & medullary respiratory system Contains areas associated with touch, pressure, vibration & proprioception Contains reflexes for swallowing, vomiting, hiccupping & sneezing Associated with 5 pairs of cranial nerves VII, IX, X, XI & XII Sheep Brain Sheep Brain Diencephalon  Diencephalon Gives rise to certain forebrain structures Thalamus – relays information from sensory receptors (auditory, visual, tactile) to the correct areas of brain for processing Hypothalamus – regulates homeostasis (water & temperature balance), appetite, thirst etc. Pineal Gland –secretion of melatonin helping with sleep regulation Cerebellum Cerebellum Plays a role in physical movement Helps with coordination, balance & equilibrium of skeletal muscles Regulates posture and balance  Cranial Nerves Know all 12 Cranial Nerves (Name & Roman #), Type (sensory/motor/mixed), transmits Nerve Impulses.