Organization of the Nervous System

1. Organization of the Nervous System

2. Meninges - 3 layers

3. Dura Mater • Superficial • Fuses brain to skull • Arachnoid • Reduces friction • Filled with CSF; shock absorber • Pia Mater • Very Vascular; needs a lot of oxygen due to high metabolic rate of neurons

4. Cerebrum • Diencephalon • Midbrain • Pons • Medulla Oblongata • Cerebellum Gross Anatomy: 6 Regions

5. Gyri: elevated ridges Sulci: furrows

7. Corpus Callosum • Bridge between Right and Left Hemispheres • Enables Right and Left sides to communicate with each other • Problems • “Split Brain” Syndrome

8. Functions: • Cognition and Memory • Prefrontal Area: involved with intellect, complex learning abilities and personality; plays a role in mood • “Gatekeeper” Judgment, critical thinking and reasoning skills • Problems • Memory loss, inability to concentrate, behavior disorder, Inappropriate social and/or sexual behavior Cerebrum: Frontal Lobe

9. Motor Areas • Function: • Motor Strip: Control voluntary motor function • Premotor Cortex: skill area; controls learned motor skills Precentral gyri • Broca’s area • Left hemisphere • Directs the muscles of tongue, throat and lips when speaking • Becomes active as we plan to speak • Syntax and grammar rules are remembered Gyri: elevated ridges Sulci: furrows

10. Try This!! Yes the bick. I would say tha the vick daysis nosis or chipickers. Represents problems with Broca’s area!! Only found in the left hemisphere of the frontal lobe Problems will affect our ability to pronounce words, speaking becomes a problem

11. Sensory Areas Located in parietal, temporal and occipital lobes Sensory Strip: Post Central Gyri

12. Parietal Lobe • Primary Somatosensory Cortex • Process sensory input from skin receptors • Proprioceptors in skeletal muscle; body orientation • Spatial Discrimination – ability to identify the body region being stimulated • Try This!! • Gustatory cortex - taste • Problems • Inability to locate and recognize body parts; disorientation • Can’t discriminate between different sensory stimuli

13. Located posterior to Primary Somatosensory Cortex • Major function to analyze different sensory stimuli (temp, pressure • Evaluate what the body is feeling • Try this!! • Different senses are distributed through all lobes Somatosensory Area

14. Temporal Lobe • Auditory Areas – sound waves are interpreted • Association area – defines the sound • Olfactory Cortex – interprets chemical odors • Language • Wernicke’s area – called the speech area • Language comprehension • Reading unfamiliar sounds • Problems • Hearing problems • Aphasia – inability to speak

15. Language Areas • Affective Language Area • Regions involved in the nonverbal, emotional pieces of language • Appears to be present in the hemispheres opposite of Broca’s and Wernicke’s area (Right side mirror image) • Voice tone and gestures express your emotions when you speak • Problems • Monotone – impairments in this area

16. Hearing and the Temporal Lobe

17. Occipital Lobe • Visual Areas • Receives stimuli from eyes • Interprets information from past experiences • Problems • Loss of vision or “seeing stars” • Can’t recognize the object you see

18. Left Hemisphere 90% is dominant for Language abilities, logic and math skills Right Hemisphere 90% is involved in visual- spatial skills, emotion, music,poetry, & creativity Stroke

19. Connects to cerebrum Includes thalamus, hypothalamus, Limbic system and pituitary gland Diencephalon

20. Thalamus • Contains relay and processing centers • Relay Station; involved in memory process • Sorts out information, edits • Gateway to cerebrum

21. Controls • Emotions, • Hormone production • Pleasure Center • Regulates Autonomic NS • Body temperature • Food intake; feeding center • Thirst • Circadian rhythms • Control of Endocrine • (ADH, oxytocin) • Problems • Hormonal Imbalances • Hypothermia • Diabetes Hypothalamus

22. Limbic System • Emotional brain • Contains amygdaloid bodies and hippocampus • Involved with learning, long-term memory and storage • Linked to emotions: rage, fear, sexual arousal • Problems • H.W. Case Study STM to LTM

23. Link between NS and Endocrine system • Produces GH and TSH • Posterior part of gland is a hormone storage area Pituitary Gland Pituitary Gland ->

24. Brain Stem: Midbrain, Pons, Medulla Oblongata • Primitive Brain • Pathway between lower brain and spinal cord and lower brain and higher brain functions

25. Contains 2 pairs of sensory nuclei (Colliculi); Auditory and Visual Reflex Centers I.e. rxns to flashlight or loud noises • Motor nuclei for 2 cranial nerves (III, IV) involved in eye movements • III Oculomotor – eye movement • IV Trochlear – rotates eye up and down • Cerebral Peduncles – descending bundles of nerve fibers • Contains your RAS center; filter for sensory input (99% of all stimulus is ignored) Midbrain

26. Colliculi of Midbrain • Corpus Quadrigemini • Superior Colliculi • Visual Reflex Centers • Associated with Cranial nerve III • Inferior Colliculi • Auditory Reflex • Startle Reflex Midbrain

27. Bridge: Connects cerebellum to brain stem; cerebrum and S. cord Relay Center Cranial Nerves (V-VIII) are attached here Respiratory Center – Involuntary Control of pace and depth Pneumotaxic Center – rapid Apneustic Center – slow Problems Hyperventilation Pons

28. Connects Brain to S. cord; relays info to Thalamus Contains major centers for Autonomic Regulation such as HR, Bp, respiration and digestive activities Cardiac Center – adjusts force and rate of heart beat Vasomotor Center – regulates BP Respiratory Center – controls rate and depth of breathing with N. Fdbk loop in pons. Controls otherpleasant body Activities: vomit, hiccupps,, cough, sneeze & gag Medulla Oblongata

29. Cerebellum • Coordination; fine tunes voluntary and involuntary movement (Sports) • Maintains balance and posture • Imbalances • Ataxia; Lack of coordination • Tremors • Alcohol – affects motor skills; reaction time

30. Cranial Nerves Olfactory – On One Optic – old Old Oculomotor – Olympus Octopus Trochlear – towering traveled Trigeminal – tops to Abducens – a a Facial – Finn familar Vestibulocochlear – valued village; Glossopharyngeal - good go Vagus – venison vanish Accessory – and and Hypoglossal – Hops. Hide.