A nose for colour

Are you the kind of person who sees a particular colour when you smell something?

Then you are one of the 6 per cent of people who have odour-colour synaesthesia –  a phenomenon where you have visual experiences when you smell odours.

Synaesthesia is an extraordinary occurrence where a sensation in one of the senses will trigger a reaction in the other senses.

The synaesthetes were also better and consistent in naming odours.

Letter-colour synaesthesia is the most common form where people see letters as having colours and this is experienced by 60 per cent of the people.

Researchers from Radboud University examined the difference between people with odour-colour synaesthesia and people without synaesthesia to understand how they think and talk about smells.

The researchers ran 6 odour-colour synaesthetes and 17 matched controls on a battery of tasks exploring odour and colour cognition.

The researchers asked synaesthetes and non-synaesthetes to name everyday odours on two separate days while testing them for odour and colour perceptions.

Synaesthetes outperformed the control group on both odour and colour discrimination tests. They showed enhanced perception in both the inducer (odour) and concurrent (colour) modality – better at discriminating colours and smells.

They also had a very different primary perceptual experience compared to the controls.

The synaesthetes were also better and consistent in naming odours.

For the first time, this study shows that people who experience vivid colour associations when they smell odours are better at distinguishing between odours and colours and in naming odours accurately.

The human sense of smell is the most underrated sense and yet with our sense of smell we each perceive our world differently. Now this study gives us more evidence about our unique sense of smell.

Source: Human Perception and Performance