1. The Brain & Cranial Nerves Structure & Funtion

2. The Brain –Introduction –Development of brain –Anatomy of brain Parts and functions

3. Introduction to the Brain –Weighs about 3 lbs. in adults –Structures Divided into 3 general areas –Functions Controls the bare necessities of life Location for primal drives and emotions Intellectual thought, imagination, perception, interpretation, etc.

4. Human Anatomy, 3rd edition Prentice Hall, © 2001 Adult Brain –Forebrain Cerebrum Thalamus & hypothalamus –Midbrain –Hindbrain Cerebellum & pons Medulla oblongata

5. Human Anatomy, 3rd edition Prentice Hall, © 2001 Protections and Coverings –Cranial bones –Meninges –3 Part Structure Dura mater –Tough Outside Arachnoid –Form Web-like Spaces Pia mater –Flexible Inner Layer

6. Human Anatomy, 3rd edition Prentice Hall, © 2001 The Ventricles of the Brain –Hollow areas within the brain Connect to spinal canal and space around the brain

7. Human Anatomy, 3rd edition Prentice Hall, © 2001 Ventricles of the Brain

8. Human Anatomy, 3rd edition Prentice Hall, © 2001 Cerebrospinal Fluid –Choroid Plexus- Filters CSF form blood –Composition Clear, colorless, watery Contains proteins, glucose, urea, salts Contains white blood cells –Functions “Floats” the brain Medium of transport –Formed by specialized cells along edges of ventricles

9. Human Anatomy, 3rd edition Prentice Hall, © 2001 Circulation of Cerebrospinal Fluid –Cerebrospinal fluid circulates around the brain, down through the ventricles, and into the spinal cord.

10. Human Anatomy, 3rd edition Prentice Hall, © 2001 Problems Associated with CSF –Disorders Hydrocephalus Meningitis Headaches Concussions –Treatments Lumbar Puncture Hormone Treatment CFS Catheter & Stints

11. Human Anatomy, 3rd edition Prentice Hall, © 2001 Blood-Brain Barrier –A function of glial cells Secrete chemicals that maintain the BBB Absorb materials from blood Extract materials from brain –Cells of capillaries form tight junctions –Differential rates of passage of certain materials

12. Human Anatomy, 3rd edition Prentice Hall, © 2001 The Parts of the Brain Forebrain Cerebrum, Hypothalamus, Thalamus

13. Human Anatomy, 3rd edition Prentice Hall, © 2001 Cerebrum – Gray & White Matter –Outer layer Cerebral cortex –Gray matter –Functional Portion –Inner portion White matter Cerebral nuclei –Masses of gray matter

14. Human Anatomy, 3rd edition Prentice Hall, © 2001 Cerebral Cortex –Gyri are separated by grooves (sulci) Fissures – deeper grooves –Divided into cerebral hemispheres –Connected by the Corpus Callosum

15. Human Anatomy, 3rd edition Prentice Hall, © 2001 Cerebral Cortex –Divided into lobes –Well mapped Decision-making, planning, personality Primary motor cortex Primary sensory cortex

16. Homunculus Primary Motor CortexPrimary Sensory Cortex

17. Human Anatomy, 3rd edition Prentice Hall, © 2001 Cerebral Nuclei –Collections of cell bodies (gray matter) –Mostly control the movement of skeletal muscles

18. Human Anatomy, 3rd edition Prentice Hall, © 2001 Limbic System –Functional unit –Emotional part of the brain Feelings of fear, loss, love, rage, etc. –Includes parts of several anatomical structures Cerebrum Hypothalamus Thalamus

19. Human Anatomy, 3rd edition Prentice Hall, © 2001 Hypothalamus –Location – under thalamus –Structure Clusters of nerve cell bodies –Autonomic centers Infundibulum

20. Hypothalamus –Secretes Hormones- ADH –Initiates primal drives Hunger, thirst, sex, rage, etc. Controls autonomic nervous system –“fight or flight” sympathetic response –Helps control pituitary gland (“master gland” of endocrine system) Infundibulum (“funnel”) funnels secretions to the pituitary gland

21. Human Anatomy, 3rd edition Prentice Hall, © 2001 Thalamus –Functions as a relay station between the body and the cerebral cortex Inform us of our emotional state Relay information concerned with motor requirements & actions Integrate visual and auditory reflexes Parasympathetic response

22. Human Anatomy, 3rd edition Prentice Hall, © 2001 Epithalamus –Location Above thalamus –Contains the pineal body Secretes melatonin (circadian rhythm)

23. Human Anatomy, 3rd edition Prentice Hall, © 2001 Midbrain

24. Human Anatomy, 3rd edition Prentice Hall, © 2001 Midbrain –Relay station –Tracts of motor and sensory neurons –Contains nuclei Substantia nigra secretes dopamine (what’s this?) –Modifies muscle tone & motor activity –Parkinson’s disease & drugs

25. Human Anatomy, 3rd edition Prentice Hall, © 2001 Hindbrain Cerebellum, Pons, & Medulla Oblongata

26. Human Anatomy, 3rd edition Prentice Hall, © 2001 Cerebellum –2 nd largest structure of the brain –Divided into 2 lateral hemispheres –Cortex – gyri & sulci Gray matter –Interior White matter –Cerebellar nuclei – deep within white matter Gray matter

27. Cerebellum –Functions – controls subconscious movements in skeletal muscle Coordination Posture Balance

28. Human Anatomy, 3rd edition Prentice Hall, © 2001 Pons –Pons = “bridge” Connects the spinal cord with the brain and parts of the brain with each other Consists mostly of white fibers –Functions Controls respiration rate (with medulla)

29. Human Anatomy, 3rd edition Prentice Hall, © 2001 Medulla Oblongata –Continuation of spinal cord –Functions Maintains wakefulness and alertness Contains reflex centers –Cardiac center, vasomotor center, respiratory rythmicity center

30. Human Anatomy, 3rd edition Prentice Hall, © 2001 Cranial Nerves

31. Human Anatomy, 3rd edition Prentice Hall, © 2001 Introduction to Cranial Nerves –12 pairs –Leave the skull through foramina –Types Mixed Sensory Motor –Part of the somatic nervous system –Innervate organs in head, neck and upper thorax