THE CHEMICAL SENSES

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THE CHEMICAL SENSES

• D. C. MIKULECKY
• PROFESSOR OF PHYSIOLOGY

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TASTE SENSATION

• GUSTATORY RECEPTORS
• GUSTATORY PATHWAYS

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TASTE QUALITIES ASSOCIATED WITH DIFFERENT AREAS
OF THE TONGUE
BITTER
SALTY
SOUR
SWEET
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GUSTATORY INNERVATION
CHORDA TYMPANI BRANCH OF FACIAL
GLOSSOPHARYNGEAL
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GUSTATORY RECEPTORS

• TASTE BUDS ON TONGUE LOCALIZED
• SWEET TIP
• BITTERBACK
• SOUR SIDES
• SALT FRONT

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GUSTATORY PATHWAYS

• VII, IX, X CRANIAL NERVES
• TO GUSTATORY NUCLEUS IN BRAIN STEM
• VPM NUCLEUS OF THALAMUS
• GUSTATORY AREA OF NEOCORTEX (POSTCENTRAL GYRUS)
• VIA LIMBIC SYSTEM TO HYPOTHALAMUS

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THE OLIFACTORY SYSTEM

• RECEPTOR CELLS IN OLIFACTORY MUCOSAL MEMBRANE
• AXONS CROSS CRIBIFORM PLATE AND TERMINATE ON
  MITRAL AND TUFTED CELLS IN OLIFACTORY BULB-FORM
  OLIFACTORY TRACT
• OLIFACTORY TRACT GOES TO LIMBIC SYSTEM AND TO
  ORBITOFRONTAL CORTEX
• CLOSELY ASSOCIATED WITH EATING AND MATING BEHAVIOR

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OLIFACTORY BULB
TUFTED AND MITRAL CELLS
CRIBIFORM PLATE
OLIFACTORY MUCOSA