Study shows adults can be trained to experience Synesthesia
What if I told you that, for some people, eating a piece of toast is music to their ears? Your first thought might be that I am making a somewhat unusual metaphor to describe just how amazing toast is for certain individuals. In actuality, there is a rare condition called synesthesia that allows individuals to have two or more senses intertwine with each other. For some, this manifests itself in such a way that taste and sound entwine; but the most common expression of this phenomenon is that of grapheme-colour synesthesia (GCS) — where an individual interprets letters or numbers as colours.
What is fascinating about this condition is that a new study published in Scientific Reports has found that by doing daily brain exercises, individuals can be trained to have different perceptions of colours to black font. Conducted at the University of Sussex, Daniel Bor and Nicolas Rothen led colleagues in a nine-week period with 14 participants. For 30 minutes a day, the group would be trained to associate 13 letters from the English alphabet to certain colours. By the end of the study, a majority of participants exhibited phenomenological experiences that were very similar to the responses of genuine GCS. Some even reported that they felt certain emotions toward letters, like X was boring and W calm.
Study shows that some human brains can be guided for the production of Synesthesia, a neurological condition in which the brain perceives stimuli as a combination of two or more senses. Photo Courtesy David Foltz CC BY-ND 2.0.
The group increased in 12 IQ points between the start and finish of the study. It is likely the training, more than the synesthesia itself, is behind the change. IQ tests are largely reliant on pattern recognition and memory and the testing session, lasting around three hours before and after training, included working memory and long-term memory assessments, among others, which could attribute to this improvement.
Dr. Rothen made clear the study’s results:
“It should be emphasised that we are not claiming to have trained non-synaesthetes to become genuine synaesthetes. When we retested our participants three months after training, they had largely lost the experience of ‘seeing’ colours when thinking about the letters. But it does show that synaesthesia is likely to have a major developmental component, starting for many people in childhood.”
The cause of synesthesia is still a matter of debate; some argue that it is a genetic component while others argue it comes from environmental influences. For example, the neonatal hypothesis brings forward the hypothesis that all people are born with synesthesia, but as we develop and mature, the neuronal connections are pruned such that we no longer associate colours, emotions, and tastes with other senses. The few who grew up with synesthesia would have had reduced neuronal pruning in comparison.
Provisional polygenetic evidence suggests that there is indeed a genetic component, but when scientists look at monozygotic twins, where one twin has synesthesia but the other doesn’t, it seems that the genetic component is actually only moderate. The fact that most GCS conditions tend to emerge in the early stages of schooling raises the possibility that there is a considerable learning component.
Bor’s study seems to support this hypothesis:
“It is possible that learning pressures, for instance for digits and letters, during early school years in certain individuals may lead to the formation of various semantic hooks, to aid memory, with color-letter associations a prime candidate. These habitual memory aids may then crystallize into synesthetic traits.”
The study has further implications: Bor, at a press conference, noted that one of the main implications is that profound new ways to perceive the world could be brought about by undergoing extensive perceptual training. Though temporary, this could led to cognitive training tools that might aid in treating individuals with sensory processing disorders, which occupational therapist and neuroscientist Dr. A.J. Ayres equates to a neurological “traffic jam.” Two vulnerable groups fall under this category: those with Attention Deficit Hyperactivity Disorder (ADHD) and adults suffering from dementia.
As the study hopes to continue research, moving on to different languages that participants do not already know to see if the effect will last longer, it will be interesting to see the extent to which we can train ourselves in perceiving a whole new world.