Why do smells trigger memories?

Written By Unknown on Kamis, 17 April 2014 | 20.01

Scientists have revealed how smells can stick to memories through an association with brain activity. Well, that's certainly good to nose. Source: ThinkStock

WHETHER it's a perfume that reminds you of a loved one or one whiff of Play-Doh that whisks you back to your infant years — how can a smell stick to a memory and be triggered off at a sniff?

The phenomenon has been studied by researchers at the Kavli Institute for Systems Neuroscience in California and have found that odours connect to memories through brain waves synchronising with the smell.

Science Daily reports the findings explain this association is linked through neural networks. As the signal arrives through your nose, different brain regions "speak to each other" activating waves of 20-40Hz.

The hippocampus controls short and long term memory and signals are sent when smells are detected. Source: Wiki Commons Source: Supplied

Using rats as research they were placed in a maze where strategically placed smells would inform the rodent where food could be found. After three weeks of training it chose correctly 85 per cent of the time. After this, electrodes were placed in the hippocampus (the part of the brain that controls memory) and when the same smell was presented to the rat, a burst of brain activity in the 20Hz range was detected suggesting that an association between smell and place had been established.

So (in the most non-scientific explanation) it essentially means fragrances cause your brain to translate the scent into memories by matching up with signals fired when you first sniffed it all those years ago. If you think of your brain like a map each recorded smell is placed like a pin in it.

We'd like to think the smell of ice cream takes us back to our childhood but, in a tragic reality, it took us back to last night.