Project “Parfum d’images”: the influence of odours on the visual memory of infants

Objectives of the project “Parfum d’images”

  • To measure the ability of the 4-6 month old infant to recognise the images presented during the project.
  • To encourage this visual memory by prior association with a smell

Impacts of the project / Expected results

To define how the association between several senses improves the first learning of infants and thus facilitates the recognition of what the infants have previously encountered.

  • Budget : €5500

Can smells help infants to better remember visual events?

To answer this question, the project “Parfum d’images” proposes to measure the impact of an odour-image association on the 4-6 month old infant’s ability to recognise images in the presence of the odour.

Newborns rely heavily on the odour signals they perceive to understand their environment. For example, the smell of its mother helps it to orient itself towards the breast and stimulates the opening of its eyes. After a few months, it even directs the infant’s gaze towards faces and facilitates perception. It has therefore been shown that an early sense such as smell influences the development of a later sensory modality such as sight. Does this influence of smell go so far as to help infants better remember visual events previously associated with odours?

The project “Parfum d’images” measures the impact of the association of odour and images on infants

To answer this question, the “Parfum d’images” project proposes to measure the impact of an odour-image association on the ability of 4-6 month old infants to recognise images afterwards. To do this, the infants will be received twice in the laboratory. The first time, their brain activity will be measured during the presentation of numerous images. This measurement will be carried out in two different odorant contexts (using perfumes). This first measurement will make it possible to show the absence of a cerebral response to given images, still unknown to the infant, and the absence of a difference in cerebral activity between the two odorant contexts.

At the end of this first appointment, a scented book will be given to the child’s parents. It will contain some of the images presented during the experiment and will have the smell of one of the perfumes used during the experiment. The parents will then be asked to read this book every day with their child in the interval before the second appointment. The aim of this daily reading will be for the child to learn the images in association with the smell.

At their second visit to the laboratory, the infants will be tested under the same conditions as at the first appointment. This time we are expected to identify a brain response that reflects the infants’ ability to recognise the images. In particular, we expect a stronger brain response in the context of the scent associated with the book, which will indicate that images are better recognised when the scent associated with their learning is present.

“Parfum d’images”: description of the measurement method

To measure brain activity in infants, we use electroencephalography (EEG). This is a non-invasive and painless method that involves placing sensors (electrodes) on the infant’s scalp to measure the electrical activity of their brain.

Description of the method used when presenting images to infants

Infants will be shown sequences of images on a screen. By presenting the images that the infants have learned from the book at a certain rate in the sequence, we will be able to analyse the brain’s response to that rate. This will serve as a brain marker of the infant’s ability to remember these images compared to other images presented to them.

Scents associated with the images that will be presented to the infants

We will use scents that will be tested beforehand with adults to balance their pleasantness and intensity. We will use two scents: one associated with the images, the other not. The scent associated with the images will be switched between infants to ensure that we are not observing the effect of one particular scent, but the impact of any scent on the infant’s visual memory.