Like the nose, lungs have odor receptors. But instead of sending nerve impulses to the brain that conjure up a burning cigarette or a cup of coffee, these receptors send a signal that may make you cough. Unlike the receptors in your nose, which are located in the membranes of nerve cells, the ones in the lungs are in the membranes of the flask-shaped neuroendocrine cells that at times are triggered to dump hormones that make airways constrict.

— Futurity, reporting on new research from Washington University in St. Louis and the University of Iowa. Read more at Odor 'Guards' in Lungs Can Make Us Cough.

Most people – including scientists – assumed we can't just sniff out danger. It was thought that we become afraid of an odor – such as leaking gas – only after information about a scary scent is processed by our brain. But neuroscientists at Rutgers University studying the olfactory – sense of smell – system in mice have discovered that this fear reaction can occur at the sensory level, even before the brain has the opportunity to interpret that the odor could mean trouble.

— Read more at Sniffing out danger: Rutgers scientists say fearful memories can trigger heightened sense of smell at Science Codex.

The regions of the brain associated with olfaction are more developed in professional perfumers than in the general population. In addition, the quantity of grey matter in the experts' olfactory regions increases in proportion to their experience. [...] Based on anatomical MRI scans of professional perfumers, perfumery students and control subjects, it shows that training and practice make it possible to reverse the age-related grey matter reduction observed in olfactory regions among the general population.

— For the rest of us, these regions of the brain tend to shrink with age. Read more at Experience modifies the perfumer's brain at CNRS. They scanned the brains of perfumer Jean-Claude Ellena and students at the ISIPCA perfumery school, among others.

We all think we know how certain things smell. But to someone else that same bottle of perfume - or piece of cheese, or glass of wine - may smell completely differently. American scientists have discovered that we all experience odours in a completely different way. Their paper, published in the Nature Neuroscience journal, reveals that 30 per cent of smell receptors differ between any two people.

— Read more at Why perfume smells different to each of us: Receptors in the nose vary by 30% in two different people at the Daily Mail.