Nowadays, on health food counters, a customer may find odor-free garlic capsules, labeled "sociable garlic". This is nothing less than unthinkable to a purist such as Harris, champion of the bulb-snatchers.
Using mutants of odor receptors, we have found that odor receptors with similar electrophysiological responses to odors across concentrations play non-redundant roles in odor coding at specific odor concentrations.
Finally, we have found that odor receptor mutant larvae have behavioral phenotypes in response to odors that are weak electrophysiological ligands, consistent with the role of olfactory sensory neurons allowing gain control of the olfactory circuit.
Researchers found an odor identification test useful in predicting cognitive decline and detecting early-stage Alzheimer's disease.
Such feature selectivity by small number of spikes (sparse coding) is found for odor coding in the insect mushroom body [56] and mammalian olfactory cortex [57], for song syllable sequence in the song bird premotor area [58], and for constructing an acoustic image by multiple delays in the echolocating bat AI [59].
If you haven't found the odor source, check the glove compartment, ash receptacles, trunk, and beneath seats.
Consistent with this conclusion, a recent study of larval odor receptors found that the odor acetal, which elicits electrophysiological activity only in Or42b, elicits the strongest behavioral response of a tested panel of odors, whereas odors that elicit strong activity from other receptors do not elicit large chemotaxis behavioral responses (Mathew et al., 2013).
The researchers found that odors that were initially rated as being neutral were rated as unpleasant after the participants had been made to feel anxious.
We found that odor-evoked ASEL activity required the canonical insulin receptor (daf-2 in C. elegans [ Pierce et al., 2001]) and PI3-Kinase (age-1 in C. elegans [ Morris et al., 1996]) signaling in ASEL neurons.
While we did not measure health outcomes or quality of life indicators, other studies of communities located within two to three miles (3.2 to 4.8 km) of an IFAP facility [ 12, 15, 16], found that odors and ammonia can contribute to poor quality of life even at ammonia concentrations currently considered not to be a risk to health.
