CHAPTER 11 NERVOUS SYSTEM II

1. CHAPTER 11NERVOUS SYSTEM II DIVISIONS OF THE NERVOUS SYSTEM

2. CENTRAL NERVOUS SYSTEM PARTS: BRAIN SPINAL CORD

3. MENINGES DURA MATER TOUGH, WHITE, DENSE WHITE CONNECTIVE TISSUE PERIOSTEUM OF SKULL BONES BLOOD VESSELS SOME AREAS PENETRATE BETWEEN BRAIN LOBES DURAL SINUSES (VENOUS BLOOD) CONTINUES DOWN AROUND SPINAL CORD EPIDURAL SPACE: BLOOD VESSELS, CONNECTIVE TISSUE, ADIPOSE TISSUE ARACHNOID MATER THIN, WEB-LIKE NO BLOOD VESSELS ON BRAIN BUT DOESN’T DIP INTO BRAIN SUBARACHNOID SPACE: CEREBROSPINAL FLUID PIA MATER THIN MANY NERVES AND BLOOD VESSELS TO NOURISH BRAIN & SPINAL CORD CELLS

4. VENTRICLES 4 INTERCONNECTED CAVITIES IN BRAIN AND BRAIN STEM CONNECT TO CENTRAL CANAL IN SPINAL CORD OPENS TO SUBARACHNOID SPACE CHOROID PLEXUSES: SPECIALIZED CAPILLARIES OF PIA MATER THAT SECRETE CSF COVERED BY EPENDYMAL CELLS WHICH FORM A BLOOD-CSF BARRIER REGULATES CSF COMPOSITION BY FACILLITATED DIFFUSION AND ACTIVE TRANSPORT

5. CSF 140 ML FILLS SPACE PRODUCE 500ML/DAY ???? REABSORBED AT ARACHNOID GRANULATIONS CLEAR, VISCID HAS MORE SODIUM AND LESS POTASSIUM & GLUCOSE THAN OTHER EXTRACELLULAR FLUIDS FUNCTIONS: PROTECTION: ABSORBS FORCE; NUTRITION; HOMEOSTASIS: IONIC CONCENTRATION; REMOVAL OF WASTE; PROBABLY TELLS AUTONMOMIC SYSTEM WHAT IS HAPPENING

6. SPINAL CORD FROM FORAMEN MAGNUM TO 1ST/2ND LUMBAR VERTEBRAE 31 SEGMENTS WITH PAIR OF SPINAL NERVES THICKENINGS: WHERE? FOR? CEVICAL ENLARGEMENT LUMBAR ENLARGEMENT CONUS MEDULARIS FILUM TERMINALE TO COCCYX CAUDA EQUINA GROOVES: ANTERIOR MEDIAN FISSURE: DEEP POSTERIOR MEDIAN SULCUS: SHALLOW WHITE MATTER ON OUTSIDE/ GREY MATTER ON INSIDE GREY MATTER: MOSTLY INTERNEURONS, SOME MOTOR NEURONS WHITE MATTER: 3 DIVISIONS: ANTERIOR, LATERAL, POSTERIOR FUNICULI: MAJOR NERVE TRACTS

7. SPINAL CORD FUNCTIONS: REFLEX CENTER TRANSFER NERVE IMPULSES

8. REFLEX ARCS SIMPLEST: 2 NEURONS SENSORY RECEPTOR ON DENDRITE OF SENSORY NEURON: AFFERENT INTERNEURON: CNS: TO OTERH INTERNEURONS OR MOTOR NEURON MOTOR NEURON: EFFERENT: TO EFFECTOR EFFECTOR: SPINAL REFLEXES ARE SIMPLEST RESPONSE

9. REFLEX FUNCTIONS: MAINTAIN HOMEOSTASIS AUTOMATIC ACTIONS: SWALLOWING, SNEEZING, COGHING, & VOMITTING AUTOMATIC RESPONSES TO CHANGE IN STIMULI SENSORY RECEPTOR SENSORY NEURON  CNS: INTERNEURONS  MOTOR NEURON  EFFECTOR AFFERENT NEURON  INTERNEURON  EFFERENT NEURON SPINAL REFLEXES: SIMPLEST REST TO BRAIN

10. PATELLAR REFLEX/KNEE-JERK MONOSYNATPTIC REFLEX: 2 NEURONS: SENSORY-MOTOR STRIKING PATELLAR LIGAMENT KEEPS UPRIGHT POSITION WHEN KNEE SAGS

11. WITHDRAWAL REFLEX PAIN STIMULI SENSORY INTERNEURON  MOTOR SIGNAL TO ONE SET OF MUSCLES TO CONTRACT AND TO ANOTHER SET OF MUSCLES TO RELAX ?? IPSILATERAL FLEXOR CONTRACT/ CONTRALATERAL FLEXOR INHIBITED AND CONTRALATERAL EXTENDER CONTRACT TO TAKE SHIFT IN WEIGHT: CROSSED EXTENSOR REFLEX ALSO SENDS MESSAGE TO BRAIN ?? FUNCTION??

12. ASCENDING/DESCENDING TRACTS USUALLY ALL AXONS IN SAME TRACT ORIGINATE IN SAME PLACE AND TRAVEL TO SAME PLACE

13. ASCENDING TRACTS FASCICULUS GRACILUS & FASCICULUS CUNEATUS: POSTERIOR FUNICULI; SENSORY IMPULSES FROM SKIN, MUSCLES, JOINTS, BONES; INFO FOR TOUCH, PRESSURE AND BODY MOVEMENT; MOST CROSS ?? SPINOTHALAMIC: LATERAL AND ANTERIOR FUNICULI; FROM DIFFERENT BODY REGIONS TO BRAIN; TOCU AND PRESSURE; CROSS OVER SPINOCEREBELLAR: LATERAL FUNICULI; POSTERIOR UNCROSSED; ANTERIOR CROSSED; FROM LOWER LIMBS AND TRUNK TO CEREBELLUM FOR COORDINATION

14. DESCENDING TRACTS CORTICOSPINAL: LATERAL AND ANTERIOR FUNICULI; CROSS OVER; VOLUNTARY MUSCLE MOVEMENTS (SKELETAL MUSCLES); PYRAMIDAL TRACTS RETICULOSPINAL: LATERAL AND ANTERIOR FUNICULI; SOME LATERAL CROSS, ANTERIOR UNCROSSED; CONTROL MUSCLE TONE AND SWEAT GLANDS; EXTRAPYRAMIDAL TRACTS RUBROSPINAL: LATERAL FUNICULI; CROSS; MUSCLE COORDINATION AND MAINTENANCE OF POSTURE; EXTRAPYRAMIDAL TRACTS

15. BRAIN FUNCTIONS?? OVERSEES FUNCTIONS OF ENTIRE BODY MEMORY; SENSES/PERCEPTION; HIGHER THINKING PERSONALITY; EMOTIONS; YOU!! CEREBRUM; BRAIN STEM; CEREBELLUM

16. CEREBRUM LARGETS; 2 HEMISPHERES; CORPUS COLLOSUM GYRI; SULCHI/FISSURES: DIFFERENT IN DIFFERENT PEOPLE LONGITUDINAL FISSURE TRANSVERSE FISSURE LOBES: SAME AS SKULL BONES FRONTAL: ANTERIOR PORTION; INFRONT OF CENTRAL SULCHUS; ABOVE LATERAL SULCHUS PARIETAL: BEHIND CENTRAL SULCHUS TEMPORAL: BELOW LATERAL SULCHUS OCCIPITAL: POSTERIOR; NO DISTINCT BOUNDARY IN FRONT; TENTORIUM CEREBELLI: DURA MATER BETWEEN CEREBELLUM INSULA: DEEP UNDER LATERAL SULCHUS; SEPARATED BY CIRCULAR SULCHUS

17. CEREBRUM CEREBRAL CORTEX: THIN LAYER OF GRAY MATTER ; OUTERMOST LAYER OF CORTEX?? 75% OF ALL CELL BODIES REST: WHITE MATTER: MYELINATED NEURONS; SENSORY/MOTOR/INTERNEURON: PASSING BETWEEN HEMISPHERES OR AREAS OF CEREBRUM

18. FUNCTIONS HIGHER BRAIN FUNCTIONS: INTERPRETING SENSORY STIMULI; INITIATING VOLUNTARY MOVEMENT; MEMORY; REASONING (USING MEMORY); INTELLIGENCE; PERSONALITY FUNCTIONAL REGIONS: SENSORY: INTERPRET SENSORY INFO PRODUCING FELLINGS ASSOCIATION AREAS: ANALYZE AND INTERPRET SENSORY INFO AND PROVIDE MEMORY, REASONING, VERBALIZING, JUDGEMENT AND EMOTIONS MOTOR: CARRY INFO TO EFFECTORS FOR PROPER RESPONSE TO SENSORY INFO

19. SENSORY POSTCENTRAL GYRI OF ANTERIOR PORTION OF PARIETAL LOBE ALONG CENTRAL SULCHUS: TEMPERATURE; TOUCH; PRESSURE; PAIN; POSTERIOR PORTION OF OCCIPITAL: VISION BASE OF CENTRAL AND LATERAL SULCHI: TASTE DEEP: SMELL INFO CROSSES SO??? SIGHT AND HEARING GO TO BOTH SIDES ???? WENICKE’S AREA/SENSORY SPEECH AREA IN PARIETAL LOBE BEHIND LATERAL SULCHUS USUALLY IN LEFT HEMISPHERE: FROM VISUAL AND AUDITORY CORTEX FOR UNDERSTANDING WRITTEN AND SPOKEN LANGUAGE

20. ASSOCIATION FRONTAL LOBES: HIGHER INTELLECTUAL PROCESSES: CONCENTRATING, PLANNING, COMPLEX PROBLEM SOLVING PREFRONTAL AREAS: EMOTIONAL BEHAVIOR, AWARENESS OF CONSEQUENCES PARIETAL LOBES: HELP INTERPRET SENSORY INFO, UNDERSTANDING SPEECH, CHOOSING WORDS OF THOUGHT AND FEELING EXPRESSION, AWARENESS OF THE FORM OF OBJECTS TEMPORAL LOBES: COMPLEX SENSORY EXPERIENCES TO UNDERSTAND SPEECH AND FOR READING, STORE MEMORIES OF VISUAL SCENES, MUSIC, OTHER COMPLEX PATTERNS OCCIPITAL LOBES: ANALYZING VISUAL PATTERNS, RECOGNIZING THINGS (PEOPLE) GENERAL INTERPRETIVE AREA: (WHERE TEMPORAL, PARIETAL AND OCCIPITAL MEET) PROCESSES SENSOPRY INFO FROM ALL 3 ASSOCIATION AREAS, INTEGRATING VISUAL, AUDITORY AND OTHER SENSES FOR INTREPRETATION

21. MOTOR AREAS FRONTAL LOBES: PRIMARY MOTOR AREAS IN THE CORTEX WITH MANY LARGE PYRAMIDAL CELLS CONTROL MOST OF MOTOR ACTIVITY, BROCA’S AREA: USUALLY LEFT HEMISPHERE, COMPLEX MUSCLE ACTION FOR SPEECH, FRONTAL EYE FIELD: VOLUNTARY MOVEMENT OF EYES AND EYELIDS SEND IMPULSES TO DESCENDING TRACTS

22. HEMISPHERE DOMINANCE BOTH INVOLVED IN BASIC FUNCTIONS: RECEIVING AND ANALYZING SENSORY INFO, CONTROLING MUSCLE MOVEMENT ON OPPOSITE SIDE, STORING MEMORIES ONE SIDE (IN MOST: LEFT) DOMINANT FOR: SPEECH, WRITING, READING, COMPLEX INTELLECTUAL FUNCTIONS: VERBAL, ANALYTICAL, COMPUTATIONAL NON-DOMINANT: NONVERBAL FUNCTIONS: ORIENTATION OF BODY SPACIALLY, UNDERSTANDING MUSICAL PATTERNS, VISUAL EXPERIENCES, EMOTIONAL AND INTUITIVE THOUGHT PROCESSES,

23. MEMORY PERSISTENCE OF LEARNING WORKING/SHORT TERM MEMORY: ELECTRICAL, ONLY THERE AS LONG AS NEURONS ARE CONNECTED LONG TERM: CHANGES STRUCTURE OR FUNCTION OF NEURONS TO ENHANCE TRANSMISSION, CAN MAKE LIMITLESS SYNATIC CONNECTIONS, SOME OF WHICH REMAIN UNCHANGED FOR YEARS

24. MEMORY CONSOLIDATION TURNING SHORT TERM INTO LONG TERM LONG TERM SYNAPTIC POTENTIATION: REPEATED STIMULATION STRENGTHENS CONNECTION HIPPOCAMPUS AMYGDALA: ASSIGNS VALUE TO MEMORY

25. BASAL NUCLEI MASSES OF GREY MATTER DEEP IN CEREBRUM CAUDATE NUCLEUS, PUTAMEN, GLOBUS PALLIDUS PRODUCE DOPAMINE: INHIBITORY NEUROTRANSMITTER FACILITATE VOLUNTARY MOVEMENT BY INTERACTING WITH MOTOR CORTEX, THALAMUS AND CEREBELLUM

26. DIENCEPHALON BETWEEN HEMISPHERES ABOVE BRAINSTEM GREY MATTER THALAMUS, HYPOTHALAMUS, OPTIC TRACTS AND CHIASMA, INFUNDIBULUM, POSTERIOR PITUITARY GLAND, MAMMILARY BODIES, PINEAL GLAND

27. THALAMUS SELECTIVE GATEWAY FOR SENSORY IMPULSES (ALL BUT SMELL) TO APPROPRIATE AREAS OF CORTEX CAN RECEIVE INFO FROM ANY PART OF CORTEX SELECTS WHICH INFO TO SEND BASED ON SYNCHRONIZED ACTION POTENTIALS

28. HYPOTHALAMUS CONNECTED TO CEREBRAL CORTEX, THALAMUS, AND BRAINSTEM MAINTAINS HOMEOSTASIS BY LINKING NERVOUS AND ENDOCRINE SYSTEMS: HEART RATE ATERIAL BLOOD PRESSURE BODY TEMPERATURE WATER & ELECTROLYTE BALANCE HUNGER BODY WEIGHT MOVEMENTS AND SECRETIONS OF STOMACH & INTESTINES PRODUCTION OF NUEROSECRETORY SUBSTANCES TO TELL PITUITARY GLAND TO REGULATE GROWTH, GLANDS AND REPRODUCTIVE PHYSIOLOGY SLEEP AND WAKEFULNESS

29. LIMBIC SYSTEM CEREBRAL CORTEX, HYPOTHALAMUS, THALAMUS, BASAL NUCLEI, DEEP NUCLEI= LIMBIC SYSTEM CONTROLS EMOTIONAL EXPERIENCE AND EXPRESSION CAUSING PLEASANT OR UNPLEASANT FEELINGS ABOUT EXPERIENCES AND GUIDES BEHAVIOR FOR SURVIVAL ALSO INTERPRETS SMELL: WHICH IS WHY SMELL INFLUENCES EMOTIONS

30. BRAINSTEM CONNECTS BRAIN TO SPINAL CORD HAS MANY NERVE TRACTS AND NUCLEI (GREY MATTER) PARTS: MIDBRAIN PONS MEDULAR OBLONGATA RETICULAR FORMATION*

31. MIDBRAIN BETWEEN DIENCEPHALON AND BRAINSTEM MYELINATED NERVE FIBERS AND GREY MATTER FOR REFLEX CENTER CEREBRAL PENDUNCLES: NOTOR PATHWAYS SENSORY BUNDLES TO THALAMUS CORPORA QUADRIGEMINA: 4 NUCLEI: REFLEX CENTERS FOR VISUAL REFLEXES (SUPERIOR) AND AUDITORY REFLEXES (INFERIOR) RED NUCLEUS: COMMUNICATES WITH CEREBELLUM & SPINAL CORD CENTERS: REFLEXES FOR POSTURE

32. PONS BETWEEN MIDBRAIN AND PONS DORSAL: NERVES TO AND FROM MEDULA AND CEREBRUM VENTRAL: MESSAGES FROM CEREBRUM TO CEREBELLUM CENTER WHICH WORKS WITH MEDULLA FOR BASIC RHYTHM OF BREATHING

33. MEDULLA OBLONGATA BETWEEN PONS AND MAGNUM FORAMEN FLOOR OF FOURTH VENTRICLE NERVES TO CEREBELLUM ALL ASCENDING AND DESCENDING NERVE FIBERS PASS THROUGH WHITE MATTER ON OUTSIDE; GREY MATTER IN CENTER FORMING NUCLEI: PASS SENSORY INFO, CROSSOVER CARDIAC CENTER: INCREASE/DECREASE HEART RATE VASOMOTOR CENTER: VASOCONSTRICTION: INCREASE BLOOD PRESSURE OR OPPOSITE ACTION RESPIRATORY CENTER: ADJUSTS RATE AND DEPTH OF BREATHING, WITH PONS CONTROLS BASIC RHYTHM COUGHING, SNEEZING, SWALLOWING AND VOMITTING INJURIES TO MEDULLA: ?? FATAL

34. RETICUALR FORMATION IN MEDULLA, PONS AND MIDBRAIN: NETWORK CONNECTS HYPOTHALAMUS, BASAL NUCLEI, CEREBELLUM AND CEREBRUM WHEN STIMULATED WAKES UP CEREBRAL CORTEX DECREASED ACTIVITY= SLEEP INJURY= COMA FILTERS SENSORY INFO: KEEPS CORTEX FROM DEALING WITH UNIMPORTANT STIMULATIONREGULATE MOTOR ACTIVITIES SO MUSCLES MOVE EVENLY INHIBITS/ENHANCES SOME SPINAL REFLEXES INTENSE CEREBRAL CORTEX ACTIVITY KEEPS PERSON AWAKE

35. SLEEP SLOW-WAVE: NON-REM: DECREASING ACTIVITY OF RETICULAR FORMATION RESTFUL, DREAMLESS, REDUCED BLOOD PRESSURE AND RESPIRATORY RATE; LIGHT TO HEAVY: 4 STAGES: 70-90 MINUTES REM: PARADOXICAL SLEEP: SOME BRAIN AREAS ARE ACTIVE; DREAM SLEEP; 5-15 MINUTES; HEART AND RESPIRATORY RATES VARY

36. CEREBELLUM BELOW OCCIPITAL LOBES TWO LATERAL HEMISPHERES: SEPARATED BY FALX CEREBELLI CONNECTED BY VERMIS WHITE MATTER: ARBOR VITAE WITH GREY MATTER ON OUTSIDE CEREBELLAR PENDUNCLES: NERVE TRACTS INFERIOR: SENSORY INFO ABOUT POSITION OF BODY PARTS MIDDLE: FROM CEREBRAL CORTEX ABOUT DESIRED POSITION OF BODY PARTS SUPERIOR: MOTOR IMPULSES TO MOVE BODY TO APPROPRIATE POSITION: INCORPORATES OTHER BRAIN AREAS FOR COORDINATION AND BALANCE, EQUILIBRIUM (SEMICIRCULAR CANALS)

37. PERIPHERAL NERVOUS SYSTEM NERVES THAT BRANCH FROM CNS CRANIAL NERVES SPINAL NERVES 2 PARTS: SOMATIC: CNS TO SKIN, & SKELETAL MUSCLES: CONCIOUS AUTONOMIC: CNS TO VISCERA: SUBCONCIOUS

38. PERIPHERAL NERVES FASCIA EPINEURIUM: AROUND WHOLE NERVE; DENSE; COLLAGENOUS FIBERS PERINEURIUM: SURROUNDS FASCICLE; LOOSER CONNECTIVE TISSUE ENDONEURIUM: LOOSER CONNECTIVE TISSUE; INDIVIDUAL NEURON BLOOD VESSELS IN EPINEURIUM AND PERINEURIUM BECOME CAPPILLARIES IN ENDONEURIUM ??

39. NERVE CLASSIFICATION SENSORY MOTOR MIXED CRANIAL NERVES SPINAL NERVES

40. SUBDIVISIONS OF NERVE FIBERS IN BRAIN OR SPINAL NERVES: GENERAL SOMATIC EFFERENT FIBERS: MOTOR IMPULSES TO SKELETAL MUSCLES GENERAL VISCERAL EFFERENT FIBERS TO SMOOTH MUSCLES OR GLANDS GENERAL SOMATIC AFFERENT FIBERS FROM SKIN OR SKELETAL MUSCLES TO CNS GENERAL VISCERAL AFFERENT FIBERS FROM BLOOD VESSELS AND INTERNAL ORGANS TO CNS

41. SPECIALIZED CRANIAL NERVE FIBERS SPECIAL SOMATIC EFFERENT FIBERS: MOTOR IMPULSES TO MUSCLES FOR CHEWING, SWALLOWING AND SPEAKING SPECIAL VISCERAL AFFERENT FIBERS: SENSORY FROM OLFACTORY AND TASTE SPECIAL SOMATIC AFFERENT FIBERS: SENSORY FROM SIGHT, HEARING, AND EQUILIBRIUM

42. CRANIAL NERVES HOW MANY? 12 PAIRS ALL BUT FIRST 2 FROM BRAINSTEM SEE HANDOUT

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45. SPINAL NERVES HOW MANY: 31 PAIRS ALL BUT FIRST ARE MIXED 8 PAIRS OF CERVICAL NERVES: C1-C8 12 PAIRS OF THORACIC NERVES: TI-T12 5 PAIRS OF LUMBAR NERVES: L1-L5 5 PAIRS OF SACRAL NERVES: S1-S5 1 PAIR OF COCCYGEAL NERVES C0

46. CAUDA EQUINA ADULT SPINAL CORD ENDS???? L2 LUMBAR, SACRAL, AND COCYGEAL NERVES DESCEND TO THEIR EXITS BEYOND THE END

47. SPINAL ROOTS EACH NERVE HAS 2 ROOTS DORSAL ROOT POSTERIOR: SENSORY DORSAL ROOT GANGLION: CELL BODIES DIRECTION???? DERMATOME: AREA OF SKIN INNERVATED BY SPINAL NERVE VENTRAL ROOT ANTERIOR:MOTOR ROOT CELL BODIES IN GREY MATTER

48. SPINAL NERVES BOTH ROOTS UNITE TO FORM NERVE 4 BRANCHES MENINGEAL BRANCH: BACK INTO VENTRAL CANAL TO MENINGES, BLOOD VESSELS AND INTERVERTEBRAL LIGAMENTS DORSAL BRANCH: POSTERIORLY: INNERVATES SKIN AND MUSCLES OF BACK VENTRAL BRANCH: MAIN BRANCH, MUSCLE AND SKIN ON FRONT, SIDES AND LIMBS VISCERAL BRANCH: ONLY IN THORACIC AND LUMBAR REGIONS, TO ORGANS, PART OF AUTONOMIC NERVOUS SYSTEM

49. PLEXUSES IN ALL REGIONS BUT THORACIC AREAS NEURONS ARE RECOMBINED SO THAT ALL NEURONS GOING TO A PARTICULAR AREA TRAVEL THROUGH THE SAME NERVES EVEN IF THEY COME FROM DIFFERENT SPINAL NERVES TYPES: CERVICAL: IN NECK, BRANCHES FROM C1-C4; TO MUSCLES AND SKIN OF NECK BRACHIAL: C5-8 AND T1; TO SHOULDER AREA; 10 DIFFERENT MUSCLES LUMBOSACRAL: T12 TO C0; 5 NERVES; LOWER ABDOMEN TO FEET (SCIATIC NERVES: LARGEST/LONGEST)

50. VENTRAL BRANCHES DON’T FORM PLEXUSES; BECOME INTERCOSTAL NERVES