Love at First Sight

Valentine's Day is only two weeks away. In anticipation of this, the next blog posts will cover topics that center around the neuroscience of Love.


The idea of love at first sight has been around since the times of Plato and has since been promoted by western media [1], but does it really exist?

by raquelcarmo via pixabay

We define romantic love as a state where one experiences strong loyalty, trust, tolerance, physical attraction, and empathy toward someone [2]. However, many of these emotions require a long time to cultivate. This would contradict love at first sight from the get-go, but if “falling in love at first sight” is a continuous process as the “falling” implies, then it could also be defined as a strong readiness or certainty to develop those emotions.

The two-factor theory of emotion proposes that both physiological arousal and cognitive label are the basis for emotion [3]. As such, an increased pulse from climbing stairs might be interpreted as fear or love depending on the emotional cues present in the immediate environment; for example the person or task waiting at the end of the stairs. A study along those lines asked people before and after a rollercoaster ride to rate a photograph of a person from the opposite gender. After the ride, the participants rated the same photograph higher in terms of attractiveness and desirability to date [4].

Upon first encounter, there are a few key features which determine whether we find a person attractive. These include waist-to-hip ratio (of optimally 0.7 for women) and facial symmetry, preferably a face similar to our own [5]. Other factors require some closer observation: middle finger length, lung volumes, and metabolic rate [5]. Human fMRI studies on loving couples have revealed the brain areas activated when pictures of their partners were shown [6]. Areas involved in sight recognition and love were dopaminergic (e.g. the putamen and caudate nucleus), associated with reward, and also areas involved in somatosensory integration. Incidentally, there is a striking overlap with brain regions activated by euphoria-inducing drugs such as cocaine. The amygdala, on the other hand, deactivates the brain areas responsible for the condition of love causing depression and emotional stress or, in this cas,e a broken heart.

So, what about you? Have you seen love at first sight?


[1] http://tinyurl.com/lxk9h2v
[2] http://tinyurl.com/lqekluu
[3] Khan, Physiol Psychol, 1962
[4] Metson and Frohlich, Arch Sex Behav, 2003
[5] http://tinyurl.com/kvmzuva
[6] Ortigue et al, J Sex Med, 1999


By Rick Cornell Hellmann, PhD Student Medical Neurosciences, AG Spinal Cord Injury
This article originally appeared June 2014 volume 7, issue 02, The Neuroscience of Love