science is not static. what we know today may be obsolete tomorrow. our innate curiosity and healthy skeptical side make sure that we, as a species, can build on, question, contest, and eventually change our informational status-quo. improving and evolving are qualities that are deeply ingrained in our DNA. that is how we could advance… 

…from Aristotelian physics to good ol’ Newton… 

…from using milk as a blood substitute in transfusions to going back to blood… 

…from phrenology to just no… 

…from everyone believing that the Earth is flat to just some believing in that theory (still looking forward to seeing that flat earthers’ cruise trip to the edge of the world!) 

…from believing that pulling out teeth would cure mental illness to not thinking of that as a sound treatment… 

and so on. 

crazy stuff, right? I bet you are pretty happy about our current times, in comparison with what was happening in the past. we can only thank those people who have tried and tested what we knew before, in order to move us forward as a species.  

neuroscience is no stranger to the constant change and evolution of its knowledge base. one of the most recent and beautiful discoveries in this field concerns our hearts. did you know that our beating, blood-pumping little engines contain neurons? yes, those electrically excitable cells that form our nervous system and are responsible for processing, storing, and directing information about our insides and outsides.  

the “little brain of the heart”, as it is commonly referred to, stores around 40,000 neurons that can remember, learn, sense, feel, and communicate with the brain. as J. A. Armour, neurocardiology researcher at the Hôpital du Sacré‐Cœur de Montréal, wrote in one of his papers: “this ‘little brain’ on the heart is comprised of spatially distributed sensory (afferent), interconnecting (local circuit) and motor (adrenergic and cholinergic efferent) neurons that communicate with others in intrathoracic extracardiac ganglia, all under the tonic influence of central neuronal command and circulating catecholamines.” this is remarkable news because up until the 1990s, the concept that another organ aside from the brain would process information in a similar manner and direct commands was unheard of. of course, the heart has limited capacity when compared with our brain’s powerful neurological circuits and functions. but instead of comparing, we should try to perceive these two vital organs as different pieces of the same puzzle.  

in fact, that is exactly how they work. scientists are trying to understand the fuller picture of the role that these neurons play in our heart’s functionality and connectivity. so far, we know that: 

• the heart-brain is comprised of a complex network of different types of neurons, adding neurotransmitters, support cells, and special facilitating proteins to the mix; 
• the brain and the heart communicate both ways, and influence each other’s activity through this neural structure; 
• the heart can also act independently from the cranial brain because of this structure. 

for neuromarketers, the big news around the discovery of the heart-brain is that it opens the door to understanding our emotional being even better.  

for example, we already have sound medical proof about how experiencing deep emotions is correlated with certain heart activities and even illnesses. when we are in love, our chest swells and we feel like we can barely breathe. when we mourn someone we held dear, the same area in our bodies carries deep, smoldering pain and we get the same feeling that we can barely breathe. many experiments keep drawing the line between what our brain feels and how our heart acts. for instance, cardiologist Lauri Toivonen and his colleagues conducted a study in 1997 on healthy physicians to find out whether experiencing distress influenced their heart’s activity in any kind of way. he conducted the experiment with the help of an EKG, monitoring changes in people before and during the first 30 seconds of an emergency call. the team noticed physiological changes which indicated oxygen deprivation and abnormal heart rhythms in the healthy doctors after the calls. these two signs are linked to cardiovascular disease development. based on these findings, new ways of looking at our hearts are being developed, such as neurocardiology or cardiac psychology.   

one could also investigate possible links between this new scientific discovery and the intuitive concepts that we attach the heart, by taking cues from the way we use language. by analyzing our vocabulary, we can gain potential insight into different aspects that cardiac neurons might be involved in. since the final form of idioms and expressions is inspired by empirical observations, one could start looking at heart-related expressions. of course, to do this,  you would need to select your language first. so let’s take English as a first example. this Germanic language abounds of heart-related idioms. statements like having “a big heart” or “a heart of stone” describe emotionally driven states of mind. “knowing one’s heart” or “having your heart in the right place” form a different category – that of feelings which arise from the chest area and relate to one’s personal identity. all these expressions create the specific context for neuroscientists to explore the link between physical input and behavioral outcome.  

the study of language from this particular angle could help neuroscientists and neurocardiologists expand on how our cultural perception influences our body awareness. you have already read some English expressions above, that allow you to form a rough opinion about how the British might relate to their heart and, more importantly, how they place the emotions which they attribute to the “heart” in the bigger picture. for example, in the case of English, the idea of “heart” stays within one word. this already indicates how the British perceive the idea of “heart” in their day-to-day interactions. but what about a different language than English, like Japanese? how do they integrate the concept of “heart” in their behaviors and expressions?

apparently, in Japanese, the cultural index for the usage of the word “heart” is high. that means that when a person tries to reference something related to the heart, there are 4 main ways of expressing the concept, each destined to be used with a specific notion in mind: we have 心 “kokoro”, 胸 “mune”, 心臓 “shinzou”, and ハート “haato”. the word “kokoro” is not only regarded as the seat of emotion, but also of thoughts and intentions (thus differentiating itself from the English idea that the mind and the heart are two opposed forces). “mune”, roughly translated as “chest” or “breast”, is thought of by Japanese as the container of emotion, and the source of “kokoro” (used in expressions about feeling joy in the heart, or about feeling your heart full). “shinzou” refers to the physical heart – this word exists due to the Japanese’s beliefs around the delimitation between the spiritual and the physical. and “haato” is usually used for the graphic depiction of a heart, used in expressions that contain words like “heart-shaped”. one interesting point to raise is that even though English and Japanese are two very different languages with separate evolutionary tracks over the years, we can notice their commonality when it comes to expressing those emotions that concern the heart. neuroscientists can take cues from such observations and dive deeper into making sense of us humans, especially since these expressions (whether in English or in Japanese) seem to go beyond the boundaries of their separate cultures. in their uniqueness, these idioms seem to be communicating a bigger, universal truth about our humanness. 

as you can see, there is plenty of material to work with if we start to cross-pollinate between sciences, and use our imagination to unlock tomorrow’s discoveries.  

if we add the cardiac neurons on top of the rich cultural, linguistic, and even spiritual legacy that we have today, the sky is the limit for neuromarketers to try and understand humans better. we just need to put a bit of heart into it. 

ps. if you think that expressions such as  “it hurts my heart” were offering clues for the eventual discovery of neurons in the heart, ever heard of “gut feelings”? well, scientists are looking into that one too. you’ll have to stay tuned for next week’s post to find out more on our fascinating second-brain that we host in our guts.