Why Love Makes Us Act So Irrationally: The Chemistry Behind A Fool In Love

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Science may not be able to tell you what love is but it can tell you what love does. Recently, new research was presented at the Society for Neuroscience meeting that has given us a small look into the brain of someone experiencing love. The sensory, molecular, and biochemical processes involved in love, as well as mating, have led human's to do some infamously foolish things. We all have a relationship or crush which caused us to act so out of character we'd rather not talk about it. So what is going on biologically to cause this drastic change in personality? As it turns out: plenty.

If you've ever been in love and offhandedly referred to it as an addiction, you were completely accurate as far as the scientific process is concerned. Both love and addiction tend to release the same chemicals. For starters the neurotransmitters dopamine, norepinephrine and seratonin are all attributed to the feeling of love at first sight. All of these are also released upon taking narcotics. However with a cultural definition as broad of love as ours is, it should be noted that this isn't the same type of love that someone feels when they might look at a picture of a model. That type of 'love' is actually more of a type of lust since its attributed mainly to sex hormones such as estrogens (including but not limited to testosterone) and androgens.

Attraction or that romantic, more passionate love that usually occurs in the first stages of a relationship is characterized by obsessive behavior, focused attention, intense craving as well as the experience of euphoria when things are going well but terrible mood swings when they aren't. This is due to extremely high dopamine, PEA (phenylethylalamine) and norepinephrine with plenty of adrenaline but low seratonin levels. 

This is the stage of love when we see people act the most irrational, impulsive and emotional; once again showing direct similarities to the emotional mind frame of addiction. The chemisty of love

Dopamine is the 'desire and reward chemical', triggering an immense rush of pleasure as a reward when its released. Its responsible for learning new behaviors and the feeling of disappointment when expected rewards are not presented. While an increase of dopamine is a biochemical reward our brain treats us to so that we know a behavior is correct; it's decrease also lets us know we are acting inappropriately and need to repeat behaviors that in the past led us to this reward. It is believed to be the underlying cause of most drug and even video game addictions.

Adrenaline increases heart rate, contracts blood vessels and dilates air passages and participates. Its the  cause of the "fight or flight" response of the sympathetic nervous system. This tends to make us particularly impulsive and irrational because it tells our body it better act quick or it's going to loose everything. People can also become addicted to the release of adrenaline which incidentally is why we have the term 'adrenaline junkies'. This might cause us to become bored and restless as the relationship progresses into it's deeper, more stable stages. So if you have a difficult time staying in a committed romantic relationship or seek out new lovers because you are addicted to the feeling of falling in love….again and again and again...This behavior doesn't just make you a jerk (although it might make you act like one), theres actual biochemical processes involved. 

Norepinephrine is similar to adrenaline in that it plays a big role in "fight or flight" responses including a direct increase in heart rate, the release of glucose from energy stores, and an increase in blood flow to skeletal muscle. Both a neurotransmitter and a hormone, norepinephrine is synthesized with dopamine. It can also cause us to act brashly upon our first impulses because it also effects your alertness, awareness, arousal and reward systems. An example of the effect of this biological process might be a tendency to act far more inappropriate then usual when jealous, jump to conclusions or become overly-anxious due to signs of trouble that may be completely unnoticeable or nonexistent to others. So once again this behavior doesn't just make you a jerk (althought it might make you act like one as well), theres actual biochemical processes involved.  

PEA is a neurotransmitter that speeds up the flow of information between nerve cells. It is released in the region of our brains known as the limbic system. The limbic system controls our basic needs, emotions, and desires such as hunger, thirst, sleep, joy, sadness, as well as sex. It is the most primal and animalistic part of our psyche. When that part of our brain kicks in, it is usually futile to disregard its directions. It's the neurotransmitter that tells you you are to hungry not to steal your friends french fries when they leave the table to go to the bathroom or to thirsty to worry about the germs all over the public water fountain therefore causing you to act before you have a chance to think more clearly.

The feeling of a true bond with someone or rather the sense of calm, peace and stability that this bond causes, is attributed to the hormones oxytocin and vasopressin which are also released during child birth, milk production and orgasms.  This illustrates why the idea that the more sex a couple has the deeper their bond is actually is scientific fact. Finally, here we see addiction's patterns differentiate because no drug can quite replicate the biochemical processes of true, deeply connected love or to be more scientific; no drug can completely replicate the release of oxytocin and vasopressin. As romantic as that may sound it also causes the loss of bounded love such as divorce or the parting of a couple thats experienced child birth especially painful since the bound is suddenly expected to be broken. As much as you may hate a person, your still chemically bounded to them. This might be why it's so common for those experiencing a nasty divorce to say things such as "Even though I hate them more then anyone else in the world...I still love them.." In fact, most domestic abuse continues behind the victim's reasoning that they  'love them to much' until a life is taken or severely threatened. 

This bring's us to the horrible experience I unaffectionately refer to as 'love withdrawals'. Dopamine receptors that have been conditioned to fire more during the period of vested love are no longer activated. Less chemicals flood the body causing withdrawal effects such as depression, laziness, anxiety, loss of interest, loss of or increased appetite, restlessness, irritability, irrationality and hopelessness.  Extreme anxiety is thought to cause abnormal neuronal activity of the nonconvulsive type in the limbic system. Which in turn is thought to result in the feeling of confused panic and a desperation to act immediately we more commonly refer to as a panic attack. 'Heartbreak' is the most famous misnomer for this intense anxiety although a feeling of 'butterflys in the stomach' is more common for the more mild forms associated with the anxiety that takes place before you make an action your mind has deemed dangerous. The PEA neurotransmitter won't be to happy with you either since after all, you failed to meet it's demands. This means your reward systems won't give you the dopamine rush you've become accustomed too, seratonin (the happy chemical) will decrease and you may even feel 'slow' as PEA is no longer speeding up neural impulses. Even evolutionary biology seems to be against our departure or loss of a committed relationship despite how unhealthy, miserable or dangerous they may be. Evolutionary biology wants us to stay monogamous because this results in the highest survival rate for our offspring. Basically, its a whole-hearted supporter of 'staying together for the kids' and is prepared to release or inhibit emotion provoking chemicals to remind you, even if you don't have any children yet. After all how should it know your parental stats?

So despite how good a couple's 'chemistry' is, it can still have some rather bad behavioral and emotional results. Love is as natural to the human life process as eating. Trying to stop will only result in hunger-pains and discomfort but eating to much is just as unhealthy as not eating at all. Therefore, it is important to remember moderation and practice self-control. In conclusion, the next time your wondering why the heck he or she makes you act like such an idiot, remind yourself it's not easy to be a sort of organic test tube with chemical reactions causing the occasional spill over and consequential mess. After all it takes the utmost self-control for most of us to moderate those crazy chemical impulses, just pick up your closest celebrity gossip magazine if you don't believe me. 


Ngozi Nwabineli
Posted on Jan 1, 2010
Posted on Dec 31, 2009