According to a recent study, the use of odours while learning and sleeping could improve our learning capacities, and even boost exam performances. The experiment’s conclusion is that if we learn things while smelling a particular scent, and then sleep next to the scent, it will be much easier for us to remember the things that we learnt. Dr. Jürgen Kornmeier, the lead author of the study, commented, “We showed that the supportive effect of fragrances works very reliably in everyday life and can be used in a targeted way.”
The challenge of consolidation
Every day, we get an incredible amount of information through all of our senses. But all this information has to be sorted and reorganised together by our brains in order to make sense. Some of the sensory information will go to our short-term or long-term memory, and some of it won’t even make the cut.
In order to learn something new, we need to convert the information from the short-term memory to the long-term memory, which is called consolidation. And for many scientists, an important goal is to know how to improve consolidation. To this day, studies have shown that consolidation during sleep was essential and that odours could also play a big part in it.
Linking smells and memories
Olfaction is one of the oldest of our senses, as it is closely related to the part of our brains dealing with emotion and memory. That’s why a smell can sometimes bring very vivid memories and transport us in time.
The link between olfaction and memory could therefore be useful to improve our learning abilities. Indeed, in a study from 2017, scientists have compared three different groups of participants, those who were exposed to a particular smell during slow wave sleep, during rapid eye movement (REM) sleep, and those who were not exposed to the smell at all. The first group performed best during memory tests being exposed to the same smell, while the last group performed worst.
The importance of smell during sleep
In another study, scientists asked 54 students to have rose scented sticks next to them while learning English, and then divided them into four groups for an exam. The first group hadn’t been exposed to any smell, the second group had been exposed while learning and during the test, the third group had been exposed while learning and every night before but not during the test, and the last group had been exposed while learning, every night before and during the test.
The two last groups of students performed a lot better during the exam than the two first groups, which led scientists to draw the conclusion that the real pivotal factor was to be exposed to the smell during sleep. According to the scientists, the students’ learning success increased by 30% when incense sticks were used during both the learning and sleeping phases.
In conclusion, the study shows that smells can be used to boost memory and that it doesn’t need to be specifically during slow wave sleep, which, according to Dr. Kornmeier, “makes the findings suitable for everyday use.”
These findings being in the end relatively limited, as they were tested on a small group of people, we can expect more research to follow soon.