1. Nervous system: The Brain By: William Maldonado, Francisco Ruiz, Esteban Perez

2. The Brain ❖ we have about 100 billion neurons ❖ Part of the Central Nervous System ➢ Brain and spinal cord ❖ The CNS Contains: ➢ neurons ➢ neuroglia - function is to protect and support neurons ■oligodendrocytes - make saltatory conduction possible ■astrocytes - maintain blood brain barrier ■microglia - do phagocytosis ■Ependymal Cells - help produce cerebrospinal fluid

3. Function ❖ Awareness of ourselves and of our environment ❖ Stream of sensory data ❖ Controls muscle movements ❖ Secretions of glands ❖ Breathing and internal temperature ❖ Every creative thought, feeling, and plan is developed by our brain ❖ Neurons record the memory of every event in our lives

4. Layers of the Meninges Function is to protect CNS Dura mater - outer layer lining skull -Surrounds and supports dural sinuses carrying blood from the brain to the heart Arachnoid mater - contains blood vessels. cushions CNS Subarachnoid space - cerebrospinal fluid protects with central nervous system with cerebrospinal fluid Pia mater - covers brain cerebrospinal fluid and contains the large blood vessels that supply the brain and spinal cord. Spinal cord reflexes - myotatic (stretch) reflex, flexor reflex,

5. Superficial Brain Structure Grey vs. White matter convolution = a “wrinkle” on the surface Gyrus = a region of the cerebrum sulcus = a shallow groove in the cerebrum fissure = a deep groove in the cerebrrum cerebral cortex = the outer few mm of the cerebrum

6. Brain Development ❖ In utero, the brain starts out as a hollow cylinder in the neutral tube ❖ develops sense of touch ❖ At 3 weeks By 3 weeks the neural plate thickens first at the head end of the embryo and folds into the neural tube which will form the brain and the spinal cord. By 3 weeks, the 3 primary sections of the brain are identifiable. These sections are called the forebrain, midbrain, and hindbrain

7. Sections of the Brain 1.Cerebrum Frontal lobe Parietal lobe Occipital lobe Temporal lobe Limbic lobe Insular cortex

8. Function of cerebrum The cerebrum is the center of the of sensory perception, memory, thoughts, judgment, and also the center of voluntary motor activity It encompasses about two-thirds of the brain mass

9. Cerebrum cont. Frontal lobe- responsible for conscious thought Parietal lobe- plays an important role in integrating sensory information from various senses

10. Cerebrum cont. Occipital lobe- responsible for sense of sight Temporal lobe- responsible for senses of smell, sound, and processing of complex stimuli Insular cortex- responsible for pain, and some other senses

11. Limbic system 2. Limbic system- it supports adrenaline flow, emotion, behavior, motivation, long-term memory, olfaction, our emotional life, and has a large part in the formation of memories Located on both sides of the thalamus, under the cerebrum

12. Cerebellum 3.cerebellum- a region of the brain that plays an important role in motor control It is located underneath the cerebral hemispheres attached to the bottom of the brain

13. Brainstem 4. Brainstem- responsible for allowing the nerve connections of the motor and sensory systems from the main part of the brain to the rest of the body It also regulates heart rate, sleeping, breathing, eating, the central nervous system, and helps maintain consciousness

14. Cranial Nerves -12 Different Nerves -Medial -Motor skills and Senses

15. Olfactory Smell: Sensory -CN1 -branch through cribriform plate -Olfactory mucosa, signal sent to olfactory bulb

16. Optic Vision: Sensory CN2 Transfers visual info to the brain.

17. Oculomotor Eyelid/Eyeball movement: Motor Connects to eye muscles and relays info from the brain.

18. Trochlear Controls superior Oblique moves eye downward and laterally. Motor

19. Trigeminal Chewing/ face & mouth touch Sensory & Motor 3 branches

20. Abducens Turns eye laterally motor Connects from pons to lateral rectus muscle

21. Facial most facial expressions/secretions Motor & sensory Many branches, each targeting a different area.

22. Vestibulocochlear hearing/equilibrium/sensations Sensory Cochlea- hearing Peripheral nerves- balance

23. Glossopharyngeal Taste/blood pressure/senses carotid sensory & motor many branches, taste ⅓ of tongue, attaches to stylopharyngeus muscle

24. Vagus -Slows heart rate -stimulates digestive system -Taste -Senses aortic B.P. Motor & Sensory

25. Spinal Accessory controls trapezius and sternocleidomastoid controls swallowing movements Motor Allows movement of head and thoracic.

26. Hypoglossal controls tongue movements. Motor Helps with digestion and the swallowing of food.

27. Reflexes Sensory info normally travels from nerves through the spine to the brain. With reflexes, the action potential loops sooner to give out a mechanical response. Potential harm avoided