Demonstrate testing for smell and taste mbbs

Physiology practical

1. PY 10.20- DEMONSTRATE TESTING FOR SMELL AND TASTE SENSATION IN A VOLUNTEER/STIMULATED ENVIRONMENT DR SWATI BANSAL (S.R.)

2. OLFACTION (SENSATION OF SMELL)

3. OLFACTORY PATHWAY

4. FACTORS AFFECTING OLFACTION Type of odorant stimulus Threshold of olfactory receptor Intensity of stimuli Olfactory adaptation (cyclic nucleotide-gated ion channel) Reflexes associated with olfaction- sniffing, salivation, gastric secretion, pancreatic secretion, sneezing, lacrimation, extreme cases- respiratory inhibition, vomiting.

5. AIM To test the smell sensation in a volunteer/stimulated environment

6. MATERIALS REQUIRED Clove Asafoetida Cardamom Coffee powder Soap

7. PROCEDURE Test each nostril separately Instruct to keep eyes and o ther nostril closed during examination. The test is repeated with a different stimulus scent.  Use familiar materials for examination like- clove oil, coffee powder, soap, toothpaste, asafoetida Purpose- To determine any impairment of smell – unilateral/bilateral Avoid – Using i rritants e.g. a mmonia for examination

8. ABNORMALITIES OF SMELL Anosmia: Complete absence of smell Hyposmia: Decreased sense of smell Parosmia: Alterations of the character of smell

9. GUSTATION (SENSE OF TASTE )

10. GUSTATORY PATHWAY

11. AIM To test the taste sensation in a volunteer/stimulated environment

12. MATERIALS REQUIRED Strong solutions of sucrose, sodium chloride, weak solutions of acetic acid, and quinine sulphate Droppers Four cards with sweet, salt, sour, and bitter written on them

13. PROCEDURE Take strong solutions of sucrose (sweet), NaCl (salty), weak solutions of acetic acid (sour), and quinine (bitter) Apply a drop of each solution to the surface of the protruded tongue The subject indicates the taste recognized by him with the help of a card that has that particular taste written on it without withdrawing the tongue Repeat the procedure with all four substances, one by one, on the sides, near the tip, the anterior two-thirds, and the posterior one-third of the dorsum of the tongue. The mouth must be rinsed properly between testing for different tastes The quinine test should be applied last (more lasting effect than the others)

14. ABNORMALITIES OF TASTE Ageusia: absence of taste Hypogeusia: decreased sensitivity to taste Dysgeusia: disturbed taste sensation

15. THANK YOU