Brain

CNS Development

Regions of the Brain Cerebral hemispheres Diencephalon Brain stem Cerebellum

Brain Stem Parts of the brain stem Midbrain Pons Medulla oblongata Slide 7.38a

Major Components of Brainstem Cranial nerve nuclei & related structures Long fiber tracts ascending and descending Cerebellar paths and circuits Reticular formation & related structures Functional Divisions Cranial nerve abnormalities Long tract deficits (motor & sensory) Ataxia (cerebellar origin) Impaired level of consciousness (RF)

Medulla oblongata Fig. 12.9 A sagittal section of the brain. (Photograph by Kevin Fitzpatrick on behalf of GKT School of Medicine, London.) 6

Medulla Oblongata functions Includes important fiber tracts Contains important control centers Heart rate control Blood pressure regulation Breathing Swallowing Vomiting Slide 7.41

Pons Fig. 12.9 A sagittal section of the brain. (Photograph by Kevin Fitzpatrick on behalf of GKT School of Medicine, London.) 9

Pons Mostly composed of fiber tracts Includes nuclei involved in the control of breathing

Brain Stem Parts of the brain stem Midbrain Pons Medulla oblongata Slide 7.38a

Midbrain Mostly composed of tracts of nerve fibers Reflex centers for vision and hearing Cerebral aquaduct Substantioa nigra Slide 7.39

Cerebellum Major Components of Brainstem Cranial nerve nuclei & related structures Long fiber tracts ascending and descending Cerebellar paths and circuits Reticular formation & related structures Functional Divisions Cranial nerve abnormalities Long tract deficits (motor & sensory) Ataxia (cerebellar origin) Impaired level of consciousness (RF)

Functions Balance

Motor Skill

Ataxia Tremor

Cerebellum and surrounding regions; sagittal view of one hemisphere Cerebellum and surrounding regions; sagittal view of one hemisphere. A: Midbrain. B: Pons. C: Medulla. D: Spinal cord. E: Fourth ventricle. F: Arbor vitae. G: Tonsil. H: Anterior lobe. I: Posterior lobe.