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Biology 202
2002 First Paper
On Serendip
Each year, billions of dollars are spent on cosmetics, facial firming, bacterial injections, double eyelid surgery, and the list goes on. All in the name of beauty. But, what is beauty? What defines it? Is there a universal beauty? Can it be obtained?
According to BBC, our perception of beauty begins in the womb. Studies show that babies have a tendency to look the longest at faces with smooth skin, round eyes, plump lips, and symmetry. In fact, BBC reports that our DNA is written to produce symmetry, yet factors such as environment produces asymmetry. Universally, these characteristics represent youth and fertility. Our faces are "an advertising hoarding which provide a potential mate with information about health, fertility and appropriateness as a partner" 1. Men look for young and healthy faces, translating to mates that are youthful with big eyes and plump lips 1. Whereas, females look for mates with the most testosterone, indicating fertility and strength. Bony protrusions such as the nose, cheek bones, brows and jaw indicate a potential for healthier children 1.
With the birth of the Golden Ratio, by Dr. Stephen Marquardt, dreams of achieving beauty have been made possible 1. This mathematically generated ratio claims to be the "essence of facial beauty" 1. It explains that the majority of people are attracted to faces that conform to the 1:1.618 Golden Ratio 1. As the founder of Marquardt Beauty Analysis in California, Dr. Stephen Marquardt and his researchers have taken it upon themselves "to develop and provide information and technology into which to analyze and positively modify (ie. improve) human visual attractiveness" 2.
So, we know that we are programmed to be attracted to beautiful faces and many of us spend our entire lives trying to understand it, but what exactly fuels our obsession?
According to a recent study done by Itzhak Aharon and his colleagues, it appears that the viewing of beautiful faces activates a reward circuitry in the brains of humans, similar to that activated when eating, having sex, using cocaine, or making money 3. The reward circuitry is activated by the neurotransmitter Dopamine, which is produced in the nucleus accumbens and released in the ventral tegmentum of the midbrain 4. Dopamine serves many purposes, for example it is needed for learning and memory processes 5, but for the purposes of this study, Dopamine is used as a method of motivating behavior 3. When a desired behavior is performed, a release of dopamine gives the person a sense of pleasure, causing a willingness to continue, repeat, and reinforce a specific behavior.
The study 3 consists of three components using four categories of faces: average female, beautiful female, average male, and beautiful male. Their main goal was to differentiate between aesthetic and rewarding qualitites.
The first component 3 required eight young heterosexual males to rate the attractiveness of faces using a rating from 1 ("very unattractive") to 7 ("very attractive"). There was a significant difference in rating between average and beautiful for both male and female faces rated. As the number of exposures to the faces increased, the beautiful female faces increased slightly in ranking, while the average female faces decreased more in rating. Yet for the male faces, continued exposure resulted in increasing ratings for both average and beautiful faces, with the difference in rating between beautiful and average remaining the same. Regarding the viewing of female faces in the first component 3 , the increase in rating of beautiful faces and decrease in rating of average faces may be a result of a early release in dopamine. When looking at a beautiful face a little bit of dopamine is released. So, with continued exposure, when the subject views the picture, he is reminded of the first release of dopamine, then he is rewarded with another release of dopamine 6. Whereas, when looking at an average face, no dopamine is released, therefore there is no reason to continue the behavior.
The second component 3 involves fifteen young heterosexual males that were given the keypress task. In this test, the subjects were allowed forty minutes to view eighty images that were always in a new random order, meaning that the categories of faces were intermixed. The results were that the subjects only expended effort to increase the viewing time of beautiful female faces. Whereas for all the other categories, they keypressed to make the faces disappear. The additional effort to increase the viewing time of only beautiful female faces rather than both beautiful male and female in the second component 3 indicates that although the viewing of male faces may be aesthetically pleasing, it is not rewarding.
In the third component 3, the fMRI was used to monitor six specific regions of the brain that been previously associated with the reward circuitry: the nucleus accumbens, sublenticular extended amygdala fo the basal forebrain, amygdala, hypothalamus, orbitofrontal cortex, and ventral tegmentum of the midbrain. In these targeted regions, six regions of interest were selected to base the comparison between the four face categories. So, six young heterosexual males were shown a set of average faces with neutral expressions. This set would be the foundation for image focusing and centering. A couple minutes later a rapid presentation of faces intermixed with fixation points was shown, and the subjects were to focus on the fixation points. For the comparison, different signal changes were noted in the different regions or interest.
The use of the fMRI showed two important things. First, the neuroimaging patterns obtained matched those using drugs, eating, and money stimulus, indicating a generalized circuitry processing rewarding stimuli. And secondly, the similarity in signal profiles between viewing beautiful faces and using money as a stimulus, suggests that reward regions respond to reinforcing characteristics rather than aesthetics.
It is interesting to note that in the third component 3, for males viewed, either average or beautiful, no signal changes were noted. This coincides with the results of the first two components 3 demonstrating a separation between attractiveness and reward value regarding beautiful male faces. In another study 7, Berridge distinguishes the difference between "liking" and "wanting." "Liking" shows pleasure while "wanting" shows incentive motivation. Therefore, when viewing beautiful females, the subjects expressed "wanting," and while viewing beautiful males, the subjects expressed "liking."
So, then where does that leave us? Well, I am not really too sure, but those of you who are in search of this universal beauty, I would like to end with a reminder from Dr. Marquardt who still believes that beauty is in the eye of the beholder and that the ones we love and admire become more beautiful with time 1.
2) Marquardt Beauty Analysis,Official Website
3) "Beautiful Faces have Reward Value: fMRI and Behavioral Evidence"
4) Diagrams and Brief Descriptions of the Central Nervous System
5) "Increased Dopamine Release in the Human Amygdala During Performance of Cognitive Tasks"
7) "Food Reward: Brain Substrates of Wanting and Liking"