1. SOMATIC SENSORY SYSTEMS AND PAIN D. C. MIKULECKY PROFESSOR OF PHYSIOLOGY AND FACULTY MENTORING PROGRAM

2. RECEPTIVE FIELDS zSIZE DETERMINES ACUITY zLOCATION OF CELL BODY CORRESPONDS TO LOCATION AND SHAPE OF RECEPTIVE FIELD zTHIS ORGANIZATION IS PRESERVED IN THE SOMATOTOPIC MAPS IN THE SOMATIC SENSORY CORTEX RECEPTIVE FIELDS TUTORIAL

3. RECEPTIVE FIELDS BY CELL BODY LOCATION: DORSAL ROOT GANGLION + +

4. + +

5. RECEPTIVE FIELDS BY CELL BODY LOCATION: DORSAL COLUMN NUCLEI INHIBITORY INTERNEURON HIGH OUTPUT

6. RECEPTIVE FIELDS BY CELL BODY LOCATION: DORSAL COLUMN NUCLEI INHIBITORY INTERNEURON SMALL OUTPUT

7. ANNULAR RECEPTIVE FIELDS - - + DORSAL COLUMN NERVE CELLS

8. ANNULAR RECEPTIVE FIELDS + - - - -

9. DIFFERENT TYPES OF RECEPTIVE FIELDS

10. OVERLAPPING ANNULAR RECEPTIVE FIELDS ARE RECTANGULAR - + - - - - + - - - - + - - -

11. SOMATOSENSORY CORTEX zSOMATOTOPIC ORGANIZATION zMORE AREA TAKEN BY SENSITIVE REGIONS (GREATER RECEPTOR DENSITY-SMALLER RECEPTIVE FIELDS) zCELLS RESPONDING TO ONE TYPE OF SENSATION IN VERTICLE COLUMNS(FOR EXAMPLE..PACINIAN CORPUSCLES IN A FINGERTIP)

12. THE ANTEROLATERAL PAIN AND TEMPERATURE PATHWAY zSENSORY NEURONS SYNAPSE IN SUBSTANTIA GELATINOSA zSECONDARY NEURONS CROSS MIDLINE AND ASCEND IN ATEROLATERAL COLUMN zBRANCHES GO TO THE RETICULAR FORMATION zTERMINATE IN VENTROBASAL NUCLEUS OF THALMUS zTERTIARY NEURONS GO TO SENSORY CORTEX

13. THE ANTEROLATERAL PATHWAY SUBSTANTIA GELITANOSA

14. THE SENSATION OF PAIN zFAST PAIN zSLOW PAIN zMECHANICAL PAIN zCHEMICAL PAIN zTHERMAL PAIN

15. PAIN NERVES:

16. FAST PAIN zOCCURS IN ABOUT 0.1 SECONDS zSUBJECTIVE DESCRIPTION:SHARP, ACUTE, ELECTRIC OR PRICKING zA  FIBERS SYNAPSE ON CELLS IN LAMINA I (LAMINA MARGINALIS) IN THE DORSAL HORNS zSECONDARY NEURONS CROSS AND TRAVEL THROUGH THE ANTEROLATERAL PATHWAY TO THE VENTROBASAL COMPLEX OF THE THALAMUS zTERTIARY NEURONS GO TO THE PRIMARY SENSORY CORTEX

17. FAST PAIN PATHWAY I II III IV V VI IX VII VIII SUBSTANTIA GELITANOSA LAMINA MARGINALIS VENTROBASAL NUCLEUS ANTEROLATERAL PATHWAY

18. SLOW PAIN zOCCURS AFTER A SECOND OR MORE zOFTEN ASSOCIATED WITH TISSUE DESTRUCTION zSUBJECTIVELY DESCRIBED AS BURNING, ACHING,THROBBING, NAUSEOUS, OR CHRONIC zC FIBERS WHICH SYNAPSE IN THE SUBSTANTIA GELITANOSA zFINAL PROJECTION IS THE FRONTAL CORTEX

19. SLOW PAIN PATHWAY I II III IV V VI IX VII VIII SUBSTANTIA GELITANOSA LAMINA MARGINALIS VENTROBASAL NUCLEUS ANTEROLATERAL PATHWAY

20. MECHANICAL, CHEMICAL AND THERMAL PAIN zFAST PAIN IS GENERALLY MECHANICAL OR THERMAL zSLOW PAIN CAN BE ALL THREE zCHEMICAL PAIN RECEPTORS: BRADYKININ, SEROTONIN, HISTAMINE, POTASSIUM IONS, ACIDS, ACETYL CHOLINE AND PROTEOLYTIC ENZYMES zPROSTAGLANDINS ENHANCE PAIN SENSATION

21. BRAIN STRUCTURES AND PAIN zCOMPLETE REMOVAL OF THE SENSORY CORTEX DOES NOT DESTROY THE ABILITY TO PERCIEVE PAIN zSTIMULATION OF THE SENSORY CORTEX EVOKES A SENSATION OF PAIN

22. PAIN CONTROL (ANALGESIA) zTHE ANALGESIA SYSTEM zTHE BRAIN’S OPIATE SYSTEM zINHIBITION OF PAIN BY TACTILE STIMULATION zTREATMENT OF PAIN BY ELECTRICAL STIMULATION zREFERED PAIN

23. THE ANALGESIA SYSTEM zPREAQUEDUCTAL GRAY zRAPHE MAGNUS NUCLEUS zPAIN INHIBITORY COMPLEX IN DORSAL HORNS

24. PAIN INHIBITORY COMPLEX: PRESYNAPTIC INHIBITION PAIN RECEPTOR BRAIN STEM.NEURON INHIBITORY NEURON ANTEROLATERAL PATHWAY DORSAL HORN OF SPINAL CORD + -

25. PAIN TRANSMISSION AND INHIBITION zSUBSTANCE P IS THE NEUROTRANSMITTER: BUILDS UP SLOWLY IN THE JUNCTION AND IS SLOWLY DESTROYED zPRESYNAPTIC INHIBITION BY INHIBITORY NEURON BLOCKS THE RELEASE OF SUBSTANCE P (ENKEPHALIN)

26. THE BRAIN’S OPIATE SYSTEM zOPIATE RECEPTORS EXIST IN MANY CENTERS OF THE BRAIN, ESPECIALLY IN THE ANALGESIA SYSTEM zAMONG THE NATURAL SUBSTANCES WHICH ACTIVATE THESE RECEPTORS ARE: ENDORPHINS, ENKEPHALINS, AND MORPHINE

27. INHIBITION OF PAIN BY TACTILE STIMULATION zSTIMULATION OF LARGE SENSORY FIBERS FOR TACTILE SENSATION INHIBITS PAIN TRANSMISSION FOR SAME REGION zRUBBING OFTEN EASES PAIN zLINAMENTS, OIL OF CLOVE, ETC. zPOSSIBLE EXPLANATION FOR ACUPUNCTURE?

28. TREATMENT OF PAIN BY ELECTRICAL STIMULATION zSTIMULATION OF LARGE SENSORY NERVES zELECTRODES IN SKIN OR SPINAL IMPLANTS zINTRALAMINAR NUCLEUS OF THALAMUS

29. REFERED PAIN zVISCERAL PAIN FIBERS SYNAPSE ON SAME SECONDARY NEURONS AS RECEIVE PAIN FIBERS FROM SKIN