PNAS, indicates that we process unpleasant smells much faster than positive smells. This response probably occurs so we can respond quickly to any perceived threats.
Unsurprisingly, negative aromas trigger a physical avoidance response when the brain signals to the nervous system. ADVERTISEMENT “The human avoidance response to unpleasant smells associated with danger has long been seen as a conscious cognitive process, but our study shows for the first time that it’s unconscious and extremely rapid,” says the study’s first author Behzad Iravani, a researcher at the Department of Clinical Neuroscience, Karolinska Institutet.The olfactory organ comprises about 5% of the human brain, allowing us to differentiate between millions of smells..
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