A new study into the human sense of smell will give hope to people who lose the ability to detect smells, say researchers.
They say people may be able to practice to improve their sense of smell, or their sense of taste which is closely linked.
The research was carried out on rats by a team at the Langone Medical Center, part of New York University, and was published in Nature Neuroscience. The rodents were exposed to different odours and rewarded when they responded to them. They then connected electrodes to the rats’ brains under anaesthetic to identify the response to smell.
The test found that different smells created different patterns of activity in the brain. Any smells that the rats thought were the same created the same pattern of activity, even if it was actually a different odour.
Another group of rats were not encouraged to react to different odours. These rats appeared to lose their sense of smell over time.
The study lead, Professor Donald Wilson, said that the research proved that a dulling of the sense of smell occurs in the piriform cortex in the brain.
The team hope that techniques can be developed to help those who lose their sense of smell through old age or illnesses such as Parkinson’s and Alzheimer’s. However, British medical experts have responded with scepticism.
Honorary secretary of the British Association of Otorhinolaryngologists, Andrew McCombe, said that loss of smell was “usually permanent and complete”, but agreed that older people should challenge themselves mentally to ensure they retained good brain function.
