Vrije Universiteit alumna and Professor of Neuropsychology in Health and Disease, Hanneke Hulst, together with other scientists, reconstructed a fragrance created by Constantijn Huygens and investigated what role scent plays in memory.

Recreating a perfume from the 17th century. How did you come up with the idea?

„The idea came from humanities scholars, Ineke Huysman and Nadine Akkerman. They worked on Constantijn Huygens’ correspondence and digitising his letters, and came across recipes for perfumes that were not previously known. Huygens was apparently a very talented creator of perfume. Together with a few scientists from various disciplines, we have brought to life one of his scents – one which had not been around for three hundred years." 

You joined the team in your capacity as a neuroscientist. What role does memory play in this project?

„The brain can link perfume or scent to emotions. If you smell the scent of a specific situation at a later stage, it can evoke strong emotions, allowing you to recall that situation very clearly. Constantijn Huygens named one of his perfumes ‘Ode de parfum: To my mother', probably because he had a good bond with his mother and wanted to keep her alive through this perfume." 

„Huygens also loved having others think of him. He used to hand out little scented bags to women from whom he was – temporarily – separated. if the romantic couple each put the little scented bag underneath their pillow, then they would somehow be together, wouldn’t they?" 

What is known about scent and memory?

„The amygdala is a region of the brain that combines various sensory information and links it to emotions. The hippocampus, the part of the brain where memories are encoded, is located right behind the amygdala. This allows emotional events to become deeply embedded, and a scent entering the brain via the olfactory nerves can trigger a specific memory." 

„This can be a positive thing. Say you have a lovely granny who often bakes apple pie. Then smelling the aroma of apple pie can make you happy, even if granny isn’t around. On the other hand, when people suffering from PTSD return from a war zone, smelling fireworks on New Year’s Eve can trigger negative memories or even panic attacks. So it’s about links to an emotion. Constantijn Huygens felt a strong tie with his mother, so much so that he wanted to make a fragrance out of it." 

Would you wear the perfume yourself?

„I’m not sure I like it. The fragrance is very strong, and spicy. Hygiene in those days was not as great as it is today, so people may have ‘smelt’ more. Maybe perfumes were used to mask those odours. Added to this, you have to be aware that perfume 300 years ago was different from today: it was not sprayed on the skin but used to perfume a room instead. The project gives you food for thought, and raises new questions. One of the ingredients for the fragrance was indeed rainwater. But is today’s rainwater comparable to what was around three hundred years ago? Eventually, we decided to go with demineralised water."

You are also doing research into multiple sclerosis (MS) at the University of Leiden. What role does memory play in your research?

„MS patients develop lesions in the brain, but also in that region of the brain where memory is located: the hippocampus. That triggers serious memory problems. As far as I’m concerned, memory is our greatest asset. It’s what makes you a human being: your memories of the past, of your friends. If something goes awry, it has major consequences for your identity and the relationships with the people around you."

„My mother had MS, and got memory problems as a result. To me, it was worse than if she had become wheelchair bound. I had to repeat everything and sometimes I got the feeling that maybe she simply didn't think that what I was saying was all that interesting. Nonsense, of course, she couldn't help it, but it took me a while to realise that." 

Are you also researching scent?

„Not really, it was really a diversion for this project. But every day I am involved in training the memory and the cognition of people with MS. The current standard is to start training the brain only when people are already suffering."

„The basic premise of my latest project, Don’t be late!, is that we must start training the brain sooner. We mustn’t wait for these cognitive disorders, which are most likely caused by brain damage, to manifest; we should strengthen the brain as much as possible even before this damage occurs. One way of doing this is through a lifestyle intervention: exercise more, eat healthy food and make sure to have enough cognitive challenges. We hope this will postpone cognitive problems, enhance quality of life and allow people with MS to participate in society for as long as possible."

Interested in hearing more about the role that scent has in memory? Then come to the flash lecture that Hanneke Hulst is giving at the Déjà VU Festival on 16 June. More information?