LECTURE NOTES IN ANATOMYPHARMACY STUDENTS; NOVEMBER 24TH

2011REV. PROF. SETH AYETTEY

OBJECTIVES• KNOW THE ROLE AND FUNCTIONAL SIGNIFICANCE

OF THE NERVOUS SYSTEM• KNOW THE ORGANIZATION OF THE NERVOUS

SYSTEM– THE PERIPHERAL NERVOUS SYSTEM

– SOMATIC– VISCERAL (AUTONOMIC)

– THE CENTRAL NERVOUS SYSTEM– BRAIN– SPINAL CORD

• KNOW ABOUT MAJOR RECEPTORS• KNOW ABOUT NEURONS AND NEUROGLIA• KNOW THE CLINICAL SIGNIFICANCE OF THE

NERVOUS SYSTEM

ROLE OF NERVOUS SYSTEMPERCEIVE & RESPOND TO CHANGES IN

EXTERNAL ENVIRONMENTINTERNAL ENVIRONMENT

TRANSPORT INFORMATION FROM PERIPHERY TO THE SPINAL CORD AND BRAIN

PROCESS INFORMATION FOR LEARNINGRESPOND TO INFORMATION TO PROTECT

THE ORGANISMFUNCTION WITHIN NORMAL PHYSIOLOGIC LIMITSNORMAL GROWTH

SURVIVAL

MAJOR PARTS OF THE NERVOUS SYSTEM 1CENTRAL NERVOUS SYSTEM (CNS)

BRAIN (FORE; MID; HIND)SPINAL CORD

CERVICAL SEGMENTS (C1-C8) THORACIC SEGMENTS (T1-12) LUMBAR SEGMENTS (L1-5) SACRAL SEGMENTS (S1-5) COCCYGEAL (1)

MAJOR PARTS OF THE NERVOUS SYSTEM 2PERIPHERAL NERVOUS SYSTEM (PNS)

SOMATIC 12 CRANIAL NERVES (PAIRS) 31 SPINAL NERVES (PAIRS)

VISCERAL (AUTONOMIC) SYMPATHETIC PARASYMPATHETIC

RECEPTORS

THE NEURONBASIC UNIT OF NERVOUS SYSTEMTYPES (FUNCTIONAL)

SENSORYMOTORINTEGRATIVE

TYPES (MORPHOLOGY)UNIPOLARBIPOLARMULTIPOLAR

NEURONAL PARTSBODY; AXONAL HILLOCKDENDRITES

RECEPTIVE FIELDPERIPHERAL PROCESS

AXONSCONDUCTS IMPULSE AWAYCENTRAL PROCESSCOLLATERALS

AXON - CONTINUEDMYELINATION

MYELINATED SCHWANN SHEATH (PNS) OLIGODENDROCYTES

UNMYELINATEDSIZE (DIAMETER)

0.2u – 20uSPEED OF CONDUCTION

(M/SEC) 5X DIAMETERGROWTH RATE - 1 mm/day

THE NEUROGLIA: OLIGODENDROCYTES

LOCATED IN BOTH GREY AND WHITE MATTER

RESPONSIBLE FOR MYELIN SHEATH FORMATION

CONTRIBUTE TO IMPULSE PROPAGATION

EQUIVALENT TO SCHWANN CELLS IN PNS

SUPPORTING CELLS (NEUROGLIA)CNS

ASTROCYTESOLIGODENDROCYTESMICROGLIAEPENDYMAL CELLS

PNSSCHAWNN CELLS

CELLS OF THE CNS: NEUROGLIA

ASTROCYTESOLIGODENDROCYTESMICROGLIAEPENDYMAL CELLS

RECEPTORS 1EXTEROCEPTORS (SUPERFICIALLY

LOCATED)PAIN (FREE NERVE ENDINGS)TEMPERATURE (ENCAPSULATED

RECEPTORS)PRESSURE (ENCAPSULATED)VISION (RETINA)OLFACTION (OLFACTORY CELLS)HEARING (COCHLEA)TASTE (TASTE BUDS)

RECEPTORS 2PROPRIOCEPTORS (LOCOMOTOR SYSTEM)

POSITION/BALANCE/MOVEMENT (VESTIBULAR APPARATUS)

STRETCH (MUSCLE SPINDLES)TENSION (TENDON ORGANS)PRESSURE/VIBRATION (PACINIAN

CORPUSCLES)

RECEPTORS 3INTEROCEPTORS

ASSOCIATED WITH VISCERA (INTERNAL ORGANS)

CONNECTED TO THE AUTONOMIC NERVOUS SYSTEM

LOCATED IN MUCOUS MEMBRANES WALLS OF VESSELS/TUBULAR STRUCTURES CONNECTIVE TISSUE OF VISCERA

TYPES FREE NERVE ENDINGS ENCAPSULATED MODIFIED EPITHELIAL CELLS

PERIPHERAL NERVOUS SYSTEMRECEPTORSAFFERENT NEURONSSPINAL CORDEFFERENT NEURONEFFECTOR ORGANCONNECTION WITH THE CNS

ORGANIZATION OF CNS 1FOREBRAIN

CEREBRAL HEMISPHERES (THE TELENCEPHALON) RECOGNITION PROCESSING INTEPRETATION STORAGE OF INFORMATION MODIFICATION OF INFORMATION RECALL UTILIZATION

ORGANIZATION OF CNS 2DIENCEPHALON

THALAMUS FINAL RELAY STATION TO CEREBRAL

HEMISPHEREHYPOTHALAMUS

REGULATION OF AUTONOMIC NERVOUS SYSTEM ENDOCRINE SYSTEM

ORGANIZATION OF CNS 3MID BRAIN

SITUATED BETWEEN FORE AND HIND BRAINS

CONNECTS FORE AND HIND BRAINS FUNCTIONALLY

HIND BRAINPONS MEDULLA CEREBELLUM

ORGANIZATION OF CNS 4SPINAL CORD

SIMPLEST FORM OF CNSINNER GREY MATTER

DORSAL HORN (SENSORY) VENTRAL HORN (MOTOR) LATERAL HORN (T1-L1-2) SYMPATHETIC OUTFLOW

OUTER WHITE MATTER DESCENDING TRACTS ASCENDING TRACTS

DIVISIONS OF THE CENTRAL NERVOUS SYSTEM – SPINAL CORDSPINAL CORD SEGMENTS

CERVICAL C1-8THORACIC T1-T12LUMBAR L1-5SACRAL S1-S5COCCYGEAL 1

ORGANIZATION OF PNSCRANIAL (12 PAIRS OF CRANIAL

NERVES)SPINAL

DORSAL ROOTS (SENSORY)VENTRAL ROOTS (MOTOR)SPINAL NERVES (MIXED)DORSAL RAMIVENTRAL RAMIDORSAL HORN (SENSORY)

VENTRAL HORN (MOTOR) LATERAL HORN (T1-L1-2) SYMPATHETIC OUTFLOW PLEXUSES

CERVICAL; BRACHIAL; LUMBAR; SACRAL