Scientists form Johns Hopkins University School of Medicine have recently found that the brain's 'nose plug' that is the switch in the brain that lets us stop smelling something, even though the odour is still there.
Two papers published in a recent issue of the journal Science show that a protein called CNGA4 helps plug the 'nose' of odour receptor cells.The main job of these neurons is to detect smells and send that information to the brain as an electrical signal.
The 'nose' is really a channel in the neurons' membrane that opens when an odour is presented and closes as the neuron becomes desensitised to that smell.By measuring the signals from these odour receptors cells in genitically engineered mice, one research team showed that mice lacking CNGA4 could sense odours but could not adapt to them.
Other scientists studied the molecule's behaviour in laboratory-grown cells and reported that CNGA4 speeds up the 'nose's closing. Without CNGA4, the closing took 100 times longer.