Olfaction

Question 1

How do we differentiate over 16,000 different odours?

Answer 1

1. Population coding
   - Different odourants activates different population of receptors in the glomerulus
   - Receptor are broadly tuned
2. Spatial coding
   - Different odourants activated specific glomeruli in olfactory bulb producing spatial maps specific to that odour
   - Different combinations of activated glomeruli correspond to different odours

Question 2

What are the factors affecting re-innervation of olfactory axons?

Answer 2

• The presence of olfactory receptors and its correct expression

Question 3

How does different odourants activates specific glomeruli in OB?

Answer 3

• Our olfactory bulb pick up the odour and detect its individual constituent
• These information are then process in higher brain region (olfactory cortex) for us to perceive it as coherent smell