PNAS: How the brain processes smell

Researchers at the University of Tokyo have created a special smell delivery device and used a machine learning-based approach to analyze electroencephalograms recorded from the scalp to discover when and where the brain processes smel.

Could the smell of a hot cup of coffee help you start your day the right way? Or you can't stand the strong, heady stuff? How fast your brain processes the smell of your morning drink may depend on a new study Whether or not you find the smell pleasa.

A team from the University of Tokyo has created a special device that emits 10 different scents precisely and in ti.

"We were surprised that we could detect odor signals from very early EEG responses, 100 milliseconds after the appearance of the odor, suggesting that the representation of odor information in the brain occurs very quick.

The brain detects smells before participants consciously perceive them, which doesn't happen until a few hundred milliseconds lat.

"The representation of unpleasantness in the brain appears earlier than pleasantness and perceived quality," said Masako Okamoto, associate professor of research program, also from the Graduate School of Agriculture and Life Scienc.

Early perception of unpleasant odors can be an early warning system for potential dang.

This high-temporal-resolution imaging of how our brains process odors may be a cornerstone for a better understanding of the mechanisms of neurodegenerative diseases in the future, such as Parkinson's disease and Alzheimer's disease, in which olfactory dysfunction is a Early warning sig.