Beauty and the Brain

The intrinsic desire for beauty bleeds into every facet of life, whether in framing one’s identity or defining the status quo. As a concept, beauty remains notoriously difficult to define, yet is ever present in day to day life, especially in relation to pleasing our egos. Beauty’s prominence has been documented since antiquity- dating back to ancient Greece through the notion of Kallos, an ideal to aspire for both physical beauty and moral integrity [1]. Although, at the time there were no scientific discoveries to cement this philosophy into fact, the new millennium has found empirical evidence to support the notion that what embodies beauty is equated to virtue in the mind of the observer. The “Beauty-is-Good” stereotype is a phenomenon in which physically attractive people are assumed to be more socially adept and morally good than others. In Ancient Greece, a woman named Phyrne was on trial for impiety and was exonerated on the basis of her beauty, as it was an indication she was favored by the gods. Beauty for our intensive purposes can be classified into facial attractiveness, audiovisual beauty, and moral goodness [2]. Audiovisual beauty is implicit to the senses, an automatic assessment of incoming stimuli based on aesthetical rules. These evaluations can be either learned, or intrinsic. For instance, humans have an automatic ability to categorize facial features as attractive or unattractive when they are just a few weeks old [2]. Moral goodness utilizes one’s higher order cognition to comprehend socially acceptable behavior. To experience moral beauty, it is necessary for emotion to accompany the judgment. In every person, there is an extremely delicate interplay between our emotions, genetic composition, and judgements that give rise to the experience of beauty, which influences one’s perception of themselves, others, and their environment. Through better understanding of why we experience beauty can a person evaluate their unconscious assumptions and conscious thought processes to redefine beauty for the better. 

Darwinian Theory of Beauty 

Beauty encompasses every facet of life: as a scenic landscape, an alluring face, the sound of a friend’s laugh, or even the movement of the body. It is a vast and complex concept that could never be simplified to language. From an evolutionary perspective, philosopher Dennis Dutton believed artistic beauty as the result of natural selection. Dutton has carefully examined evidence supporting a Darwinian theory of aesthetics. For example, before the use of language, humans that were able to sculpt the finest, most sophisticated stone axes were viewed more favorably by other humans and thought to have more advantageous features such as high intelligence and dexterity. Hence, mates were attracted to these individuals and were more likely to reproduce with them, carrying on their bloodline. Dutton says, “beauty is a gift handed down from the intelligent skills and rich emotional lives of our ancestors [3].” Although beauty is a complex concept, we widely find beauty in near flawless execution, such as the stone axes of cavemans, the fluidity of dance, a well written novel, or a masterpiece of artistic innovation. 

Natural selection, an evolutionary mechanism responsible for the adaptation and survival of various organisms, is able to seamlessly explain our biological predisposition towards revulsions and attractions. In terms of developing disgust, the area known as “postrema” has a huge role. Postrema is a brain region vital to detecting toxic substances within the blood, which triggers the vomiting reflex [4]. Consequently, when our ancestors would eat potentially poisonous food, this reflex would expunge the dangerous substance. As a result, a taste aversion would be learned [5]. This safety mechanism has proved to be an evolutionary advantage for survival while also being a clear example of how human psychology permits higher order conditioning in which the taste, smell, or sight of a certain food will trigger revulsion. Comparatively, with pleasure inducing foods rich in fats and proteins, we are more inclined to naturally enjoy them as they are the building blocks to healthy neuronal functioning [6]. Thus, in both scenarios, we see the process of natural selection strengthen pleasurable stimuli whilst simultaneously weakening harmful stimuli. 

Feelings of disgust can be aroused from either immorality, unwanted sexual advances, or bacteria. Pathogen-related variables have been correlated with judgments of physical beauty. In an experiment administering hypothetical scenarios to invoke feelings of disgust, whether imagining stepping in animal feces or sitting next to someone with open sores on their arms, those especially sensitive to repulsion were more likely to give lower attractiveness ratings to unattractive faces [7]. From an adaptive perspective, perceptions of ugliness invoke avoidance whereas beauty inspires approach motivation. As the mere sight of unpleasant faces activates the behavioral immune system, the body’s defense system against pathogenic threat. Meaning at an unconscious level unattractive people are treated like they have a contagious disease, whereas attractive people are assessed as having better health and fertility [8]. In terms of landscape humans have an aesthetic predisposition for landscapes improving survival chances such as open forests adorned with lush, diverse greenery [9]. Common attributes ascribed to beauty pertain to form and symmetry. Within every facet of nature appears the Golden Ratio or “Divine Proportion”, in which the ratio of the whole to its larger part is equivalent to the ratio of the larger part to the smaller, giving rise to perfectly symmetrical distribution between two proportions. The pattern is ubiquitous in nature appearing in various forms such as shells, clouds, flowers, galaxies, and waves. It can also be observed in man made objects such as architecture (for example the Eiffel Tower) and artwork (such as the Mona Lisa) whether intentional or incidental [10]. The significance of symmetry in our perception of beauty indicates an underlying mathematical component to what is considered beautiful. The sensation of beauty arising from mathematical structures activates the medial orbitofrontal cortex, which is aroused when experiencing moral, visual or musical beauty [11].  These characteristics also aid in survival, as a symmetrical face indicates robust genes and strong health, whereas an asymmetrical, drooping plant would reveal potential danger. Decisions we make related to survival initiate activity in the reward center of our brain, producing feelings of pleasure that encourage us to keep engaging in the behavior [12]. Beauty and ugliness arise as an adaptive effect resulting from the process of  natural selection. Experiencing the beautiful creates feelings of pleasure promoting our attraction whereas potentially harmful stimuli are viewed ill-favorably and provoke evasion.

The Universal Beauty Standard 

Infants have an inherent disposition to attend to faces compared to other stimuli at just a few days of age [13]. Interestingly they demonstrate an automatic capability to class faces as attractive or unattractive during this time period whether it be the faces of  humans or tigers. Overall this is a  reflection of general processing mechanisms rather than for reproduction [14]. These natural assumptions however are still prone to be modified due to experience, as prolonged exposure creates familiarity that can lead to attraction [15]. As brains continue to develop, they have the capacity to extract the emotional expression, gaze direction, and overall attractiveness of someone’s face in an instant. Attractive faces are able to bypass conscious processing and penetrate awareness faster by virtue of the unconscious mind [16]. Allurement is a quality valued across the animal kingdom, as various species rely on ornamentation via feathers, fur, or fins to attract a mate [17]. Captivating human faces share qualities that make them appealing across cultures, suggesting that beauty is a universal feature hardwired into our genetic composition. Meaning, attractiveness and the ability to detect it are under evolutionary pressure to be selective for favorable traits promoting survival [18]. 

Appraisal systems used to determine attractiveness typically revolve around age, health, symmetry, averageness, and sex-specific traits for reproductive success. Facial symmetry has a positive influence on perceived attractiveness [19]. One study demonstrated using a pair of identical twins that the twin with more symmetrical features was perceived to be more attractive, indicating balanced proportions proved to be more advantageous [20]. Furthermore, symmetry is also positively related to characteristics indicating fitness which in turn suggest growth rate, fertility, and survivability [21]. Other features, such as smooth, uniform skin and glossy hair are viewed as alluring whilst simultaneously indicating favorable health [22]. Averageness amongst faces refers to how closely an individual resembles the majority. Features aligning with the general population are linked to genetic diversity [21] as well as strong phenotypic conditions. In terms of sex-specific traits, females can exhibit desirability through distribution of body weight and emphasizing youthful qualities such as a small nose, small feet, and hairless skin. Low waist-hip ratio is deemed sexually attractive whilst also indicating high levels of estrogen and testosterone satisfiable for potential future reproductive function. Whereas in males their physical appearance tends to demonstrate social dominance which has the dual effect of intimidating competition and attracting mates. Sexual characteristics provide input on hormonal status and phenotypic insurance for superior genes [23]. Interestingly, the effects of conformity have an active effect on the beauty standard. All it takes is a single person to share their attraction to another for the judgment to be contagious [24]. 

All of these traits are reflective of specific psychological adaptations that cultivate survival of the fittest, or more accurately survival of the prettiest. More often than not do individuals neglect to remember wisdom bestowed from the past in the simple phrase  “don’t judge a book by its cover.” Yet, our knee-jerk assessments are seemingly impossible to halt as our first impressions help guide our internal reality to navigate the external world. The ‘attractiveness halo’ is a well documented phenomenon spanning across all eleven world regions in which those considered physically desirable are accredited preferable traits, whether more confident, conscientious, emotionally stable, extraverted, intelligent, responsible, or trustworthy [25]. Although, this assumption is driven more by the presumption that ugly equates to bad rather than beauty inherently indicating virtue [26]. As fundamentally social beings, hierarchies naturally develop in groups and status ranking based on physical attractiveness can arise, having unfavorable ramifications for those devalued based on their appearance. Good-looking people are less likely to be found guilty by juries and more likely to get a lighter sentence. At the polls, voters tend to gravitate toward more physically enticing politicians. Even in the classroom better-looking children are favored by their teachers and peers [8]. In job interviews attractive people are still more likely to get hired and on average earn 12% more than unattractive candidates [27]. Paradoxically, however, evidence suggests that in male dominated positions when a female applicant applies, the reverse effect happens. Female candidates deemed attractive are rated less favorably than their unattractive counterparts in the “beauty is beastly” effect [28]. 

Even though attractiveness has been documented to exert positive influence on social evaluation and decision making [29], the same evaluations do not always hold consistent for people of the same sex, depending on sexual orientation. Attractive same-sex members can often be perceived as a threat whilst also making the other party feel insecure [30]. Being perceived as the rival can cause others to react negatively in a jealous manner as the intimidation settles in. This perception bypasses conscious processing and can occur at an automatic, unconscious level without engaging awareness [31]. These negative responses not only extend to romantic settings, but also in organizational decision making [32]. 

The underlying neural circuitry eliciting positive responses to attractive faces are directly related to reward circuits stimulated by dopamine pathways. In an experiment using male faces ranging from pleasurable to aversive, increased activation was found in a reward circuit, activating the anterior cingulate cortex (ACC), lateral and medial orbitofrontal cortex (LOFC and MOFC), striatum (nucleus accumbens (NAC), caudate, putamen), and the ventral tegmental area (VTA). This reward system functions to guide intentional behavior, such as approach or avoidance. LOFC and putamen activation increases as attractiveness decreases. When attraction increases, the MOFC and putamen are aroused [33]. Responses in the MOFC are further amplified in the presence of a positive facial expression, such as a smile, thus enhancing the reward value of an attractive face [34]. 

Beauty in Virtue 

The medial orbitofrontal cortex has been linked with processing ‘positive stimuli’ whether it be pleasant audiovisual input, attractive faces, or in experiencing acts of morality requiring higher order cognition. In contrast, the insular cortex has been associated with ‘negative stimuli’, such as in viewing an unattractive face or in processing morally negative stimuli. Furthermore, the insular cortex has been correlated with ‘social pain’ following an unfavorable interaction whilst also being activated from interpreting negative cues from facial expressions [2]. The opposing activity between the MOFC and insular cortex during aesthetic and moral judgements supports the notion of the Beauty-is-Good bias as well as demonstrating the role of the MOFC to approach rewards and the insular cortex in avoiding punishments. The experience of moral beauty uniquely only involves the orbital frontal cortex (OFC). Additionally it spans a vaster cortical network compared to facial beauty, which reveals the complex cerebral representation necessary in experiencing moral beauty. Moral beauty is independent from perceptual beauty and comes from the comprehension of abstract social norms pertaining to expressions of humanity, virtue, and altruism. Whereas facial beauty involves the cortical reward region OFC and a subcortical reward region, the putamen [35]. Additional evidence for the OFC’s involvement in audiovisual beauty was found in a study using twenty one participants from various cultures. The partakers were instructed to rank paintings and music as beautiful, neutral, or hideous. When the participants interpreted a piece as beautiful, only one area, the MOFC activated in response to pleasurable audiovisual stimuli. The strength of activation was directly correlated to the degree of beauty participants experienced [36].  

There is a distinction between the experience of moral goodness and moral beauty. Both refer to virtues exhibited by humans, but the key difference is that moral goodness is the predecessor to experiencing moral beauty. Emotional elevation, a self-transcendent emotion characterized by inspiration and heartwarming movement, must accompany perceived moral goodness for the experience to be qualified as moral beauty. Both discernments recruit the left inferior orbitofrontal cortex, while moral beauty engaged additional brain regions involved in elated emotions consisting of the anterior cingulate cortex (ACC), medial prefrontal cortex (mPFC), superior frontal gyrus (SFG), and left temporoparietal junction (TPJ). These regions have been further implicated in moral cognition. Furthermore, when participants made assessments of moral beauty, brain regions involved in empathy–the midline structures and anterior insula–also became activated [37]. The take home message here is that the neural activity underlying facial attractiveness and moral goodness overlap, as numerous studies have documented how activity in the medial orbitofrontal cortex increases in a direct response to perceived gorgeousness and righteousness. These activations are strongly correlated to one another [2]. 

The related circuitry involved in both moral and aesthetic beauty lay the foundation for social aesthetics. Social beauty relies on the MOFC due to its involvement in facial and ethical aesthetics. The two systems influence each other, as facial attractiveness can influence personality judgment, hence the Beauty-is-Good bias. Likewise, an individual’s virtue can have a positive aesthetical influence on their facial features, in the Good-is-Beauty stereotype [38]. Positive traits, such as kindness, humility, honesty, and friendliness promote overall attractiveness whereas negative traits reduce allure [2], [39]. Having a likable personality can override physicality, suggesting character to be of more value than innate appearance [40]. 

Human societies are unique in their deep regard for morality, justice, and fairness, as the majority of people possess some semblance of morality [41]. In hierarchical societies demonstrating qualities of morality and warmth can lead to attainment of higher status [42]. The intense emotional ecstasy invoked by beauty underlies our perceptual experience and gives rise to affections of pleasure, shared universality, harmony, meaningfulness, and ecstasy [43]. There is seemingly a parallel between physical properties and virtuous characteristics as delicate objects invite gentleness, smoothness welcomes caressment, and the appreciation of these qualities invokes euphoric feelings corresponding with ecstasy. Likewise beautiful traits gravitating towards a gentle disposition create unity amongst people whether in cases of vulnerability or compassion. Other virtues igniting this response pertain to altruism and overcoming self-serving inclinations. Ecstasy is characterized by the transcendence from self and an interconnectedness to the world promoting morality, empathy, and harmony. In one study, individuals imagined three different hypothetical scenarios: a compassionate act, a just act and a neutral act. In the conditions where the individual engaged in acts of sympathy and fairness the participants viewed them to be more beautiful than the impartial control. The compassionate individual was ranked most favorably, as their empathetic nature promoted transformational ecstasy, the desire to cultivate one’s own morality [44]. Additional benefits to engaging in acts of kindness cause improvements to one’s own health and well being. Demonstrating charitability has been proven to increase serotonin and endorphin levels, hormones that promote happiness while simultaneously decreasing levels of cortisol, the stress hormone that when reduced promotes anti-inflammation which promotes anti aging and overall cell vitality [45].  Increased serotonin has also been shown to enhance one’s subjective confidence [46] which in turn is viewed as a favorable trait in a potential partner [47]. 

Conclusion 

Ecstasy is the visceral creator of beauty as it provides the emotional undercurrent for our sensory experience. Emotions guide our perception of beauty and are not always linked to the external world but rather can rely on higher order perceptions based solely on mental representations [48]. Implying any internal experience of beauty can be subject to change based on the current emotional state. As the medial orbitofrontal cortex has been implicated in both aesthetical appraisal and moral beauty, virtuous qualities enhance one’s attractiveness as compassion and morality are universally valued traits. The dichotomy of consciousness is in juxtaposition with the unconscious mind, as parts of perception are under conscious control and some are not. What is under our domain of control can be subject to change through reframing one’s chain of thought. As articulated by Mark Grief in his collection of essays, Against Everything, “Let anyone’s ordinary face fascinate you as if it were a bust of Caesar, let the lights of a city draw your eyes like Egyptian gold or the crown jewels, let a cigarette case you find on the road evoke the whole life of its imagined owner, let your fellow human beings be bearers of plot and motivation as in a work of fiction, possessors of intricate beauty or ugliness as in a painting, objects of uniqueness and fearful sublimity in a wonder of nature.”  

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