she recruited twenty-five volunteers who had a normal sense of smell and at least one specific anosmia, then had them undergo Thomas’s regimen of olfactory training. They received “smell bottles” with dilutions of the odors they were unable to smell, and sniffed them twice a day for ten seconds over the course of two to four months. Every single person showed “improved perception of the respective odors.” Not one of the participants was still odor blind to the smell they’d been unable to distinguish before.
