To answer this question we need to consider what is meant when we say love is ‘blind’. Does it mean that we silence the alarm bells and look past a potential romantic partner’s mistakes or does it mean that we are not capable of noticing a potential romantic partner’s flaws? Understanding the relationship between logic, love and decision making will help us to establish what is meant by saying love is ‘blind’. It will also help us understand how these cognitive functions and their neural circuits influence our decision making process when it comes to choosing a romantic partner and whether love causes us to be ‘blind’.

Logic and reasoning

When it comes to making decisions there are usually a few complex neural circuits involved in the process. We rely on logic and reasoning on a daily basis to make not only complex decisions but also average day-to-day decisions. We make decisions about what action we want to take and we also choose what information we will base our decisions on. Logic and reasoning may appear black and white, but they can be quite complex as we draw conclusions from considering various factors as well as the influence of various variables.

The essence of the human mind, ‘logos’, which comprises of language and logic/reasoning, is a bit more complex than we think. As humans, we are unable to separate logic and rationality in our heads, which is why, as a society, we feel the need to rationalise everything in order for us to logically make sense of the world. The idea of ‘being rational’ comes from the Greek philosopher Aristotle’s syllogism which is the kind of argument used in deductive reasoning. This can be explained by considering the following scenario;

  • My friend prefers to romantically get involved with girls who have blonde hair.
  • I have blonde hair.
  • Therefore my friend wants to get romantically involved with me.

The logic followed in this scenario does not make sense because if one thing is true, it doesn’t necessarily mean that it is applicable or true in any other scenario.

There is not a lot of neuroimaging data on logic and reasoning, and currently there is not any research on neural activity when the brain is inhibiting a perceptual process in order to activate a logical reasoning process. What we do, however, know is that we as humans are intrinsically risk averse and we tend to use logic and reasoning to minimise risks. There are usually two ways we think about things and make decisions, slow or fast, which we refer to as System 1 and System 2. System 1 thinking is almost instantaneous and sub-conscious; it happens implicitly with little effort, whereas System 2 thinking is conscious, logical, and slower and takes more effort.

We learn and reason through pattern recognition, for example, we hold hands with a loved one, and our brain releases oxytocin and dopamine, which reward us for engaging in this behaviour. Our brain now associates holding hands with a pleasurable and positive feeling and links it to two people who love each other, so we repeat the behaviour, and when we see other couples holding hands, we conclude that they are in love, when they don't, we conclude they had a fight or fell out of love.

The brain in love

It is hard to establish when we as a species started ‘falling in love’. Unlike anthropological discoveries that have physical evidence that could identify the first instance of a ‘civilised society’ for example there is no tangible evidence of the first instance we as a species started ‘falling in love’. There are, however, certain indicators from Neanderthal burial sites of a kind and loving relationship between the living and the dead, such as pollen and flowers discovered in the graves, but this does not give any insight into romantic love.

It is only as recently as 2005 that the first functional MRI (fMRI) study was conducted by Fisher. She and her team analysed 2,500 brain scans of individuals who were viewing pictures of someone who was special to them and, in a separate instance, pictures of acquaintances. They discovered that brain regions associated with dopamine, the ‘feel-good’ neurotransmitter, became active when participants viewed someone they romantically loved. Distinctive dopaminergic brain pathways were activated in two brain regions, namely the ventral tegmental area, a primitive neural network associated with focused attention, the motivation to pursue and acquire rewards and pleasure, as well as the caudate nucleus, associated with reward detection and anticipation and the integration of sensory experiences into social behaviour.

Love is stronger than basic emotions or states of mind and has the ability to reduce anxiety and fear which makes us more willing to take risks. Individuals who reported intense feelings of emotional attraction to a partner admitted that they think over 85% of their waking hours about their romantic partners. This obsessiveness is due to a decrease in serotonin. A broad body of literature over the last century has reported various physiological effects of love such as euphoria, loss of appetite, decreased need for sleep, and hyperactivity.

Very few mammals are in monogamous relationships which have made it difficult to investigate what the drivers are behind love and commitment in a human relationship. A study done one prairie voles, one of the very few mammals who mate for life, shed some light on the neurobiology behind love and monogamous romantic relationships in humans. They found that there was an increase in vasopressin and a decline in testosterone when a male prairie vole mated with a female. This means that males became less combative and bonded with their female mate. In female prairie voles there was a rise in oxytocin, the bonding hormone.

In both male and female prairie voles there was a surge in dopamine and primed by similar factors. For female prairie voles there was a significant spike in dopamine straight after mating, which indicates why the strong emotional bond human females form, due to a spike in oxytocin, with human males when having sex is strengthened. Dopamine rises in males when spending time with their mates as well as mating.

In order for certain receptors to be present certain neurotransmitters need to be present, but this takes some time which is why men tend to take longer to fall in love and commit. When men fall in love there is an increase in dopamine and vasopressin as well as testosterone, while they are ‘pursuing’ a female. When they orgasm, vasopressin decreases and after they commit testosterone drops, making them more docile and allowing them to bond with their romantic female partner. There is an increase in oxytocin, which spikes when having sex and orgasming, and progesterone which made females a bit more aggressive and loyal to their romantic male partner. This leads to the understanding that men and women fall in love at different stages and in different ways.

Choosing a romantic partner

There are various reasons people fall in love and choose a specific romantic partner; we make use of environmental factors, personal experiences, physical attributes, and even some logic and reasoning. Reasoning is inevitable when it comes to making decisions, as it forms part of the decision-making process. Choosing a romantic partner looks very different between sexes, as they value different factors due to primitive biological factors. Logic and reasoning become a lot more complex when we inject feelings and emotions into the matrix. Feelings and emotions tend to bring about judgement, which we rely on when deciding whether someone is a suitable romantic partner.

It is important to acknowledge that there are various steps involved with falling in love as well as various stages of love. One of the first steps occurs in about 30% of people and that is being drawn to someone with a relatively symmetrical face. Studies have found that individuals who with symmetrical facial features appear more intelligent, trustworthy, kind, and charming, so it does not necessarily have anything to do with beauty.

That being said physical attributes does have an influence on the partner we choose as we all have different preferences and find different physical attributes attractive. When we are physically attracted to someone there is also an increase in dopamine which strengthens our desire to be with that person. It also arouses us to engage in sex which is another step in the process of falling in love because this intimate action causes specifically females to form a deeper bond with their romantic partner.

Another factor that females usually consider, whether we like to admit it or not, when we choose a romantic partner is status. The reason we consider this is that we value security and feeling safe and protected. Someone who has a higher societal status tends to be able to better provide the security we desire.

When we choose a romantic partner we look for a balance between commonalities and differences as we need to have common ground to like each other but differences to keep us intrigued and curious. We tend to not get involved romantically with someone if we differ too much, which is why many couples drift apart some time into their relationships, because we tend to feel more comfortable with what we know.

Conclusion

Considering the research discussed above and the logos behind choosing a romantic partner to say love is blind is a bit of a stretch. The fact that we are more impulsive during the first stages of love can cause us to be less risk averse and overlook potential ‘red flags’, but this ‘blindness’ has a time limit of about 3 months. Anthropologically we are inclined to choose a mate that will best provide us with security, for females, and the most offspring, for males. This in itself indicates we have parameters when it comes to choosing a romantic partner. Love is not blind because it happens in different stages and even though it is set in motion due to neurobiological factors, it comes to a precipice where we need to make a conscious decision about whether we are going to continue loving someone or part ways. The fact that love is not blind also allows our partners to see positive qualities in us that we may not see in ourselves.

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