Olfactory senescence

Ah, the joys of senility. Apparently, this now includes eating spoiled food and the inhalation of toxic vapors. A study comparing olfactory sensory neurons (OSN) in subjects 45 or younger and 60+ found that OSNs in younger subjects exhibited highly specific responses to two distinct odours, while those in the elderly subjects were more likely to respond to multiple odor stimuli indicating a loss of specificity. Interestingly, OSN density was comparable between the two groups. This means that loss of specificity in OSNs from older subjects may contribute to smell loss and the inability to differentiate between smells. Since smell is so intimately linked to taste, this could also result in decreased tasting abilities.