A team of researchers has recently revealed that brain plays a major role between odours and nostalgia. (Photo: Pixabay)

Ever wondered as to why some smells make you nostalgic about the old days?

A team of researchers has recently revealed that brain plays a major role between odours and nostalgia by logging scents in the part of brain, which is responsible for retaining long-term memories.

The current study shows that the piriform cortex, a part of the olfactory brain, is involved in the process of saving those memories; the mechanism, however, only works in interaction with other brain areas.

Artificial sensation through stimulation - synaptic plasticity - is responsible for the retaining memories in the brain.

They explained that a memory is created, when communication between neurons is altered by means of a process called synaptic plasticity.

Ruhr-University Bochum neuroscientists Dr Christina Strauch and Prof Dr Denise Manahan-Vaughan conducted the research on brain area is responsible for storing odours as long-term memories.

"It is known that the piriform cortex is able to temporarily store olfactory memories. We wanted to know, if that applies to long-term memories as well," said Christina Strauch.

The team conducted a study on rats to examine whether the piriform cortex is capable of expressing synaptic plasticity and if the change lasts for more than four hours then it indicates that its a long-term memory.

The scientists used electrical impulses in the brain to emulate processes that trigger the encoding of an olfactory sensation as a memory.

They then stimulated a higher brain area called the orbitofrontal cortex, which is responsible for the discrimination of sensory experiences.

This time the stimulation of the brain area generated the desired change in the piriform cortex.

"Our study shows that the piriform cortex is indeed able to serve as an archive for long-term memories. But it needs instruction from the orbitofrontal cortex - a higher brain area - indicating that an event is to be stored as a long-term memory," Strauch stated.

The findings are published in the journal Cerebral Cortex.