Psychodermatology at a Glance

Psychodermatology is a relatively new field of study, diving deeper into the interplay of mental health and skin disorders. The skin and brain originate from the same embryonic tissue, the ectoderm, and remain intricately linked throughout life through neural, hormonal, and immune pathways. Therefore, the mind can influence a multitude of conditions, including eczema, psoriasis, alopecia, and acne. The simplest way of psychology manifesting into physical results is the worsened mental health that these conditions bring. For example, alopecia, which results in the loss of hair, worsens confidence and, on a broader scope, worsens mental health. This leads to a cycle of negative psychology, directly resulting in worsening conditions. Since the early days, celebrated scientists such as Hippocrates and Freud have hypothesized that stress can directly affect mental health. Though their understandings were only fundamental, it has paved the way towards our modern understanding. The contemporary understanding is that, due to the embryological link between the brain and skin (ectoderm), there are multiple mechanisms of connection. Some are the neuroendocrine, immune, cellular, and oxidative/molecular mechanisms. 

The neuroendocrine pathway is essentially there to say that when a person is experiencing stress, the hypothalamic-pituitary-adrenal (HPA) axis releases corticotropin-releasing factor (CRF), ACTH, and cortisol. These elevated levels of cortisol disrupt the skin barrier, delay wound healing, and can even prematurely shift hair follicles from the growth (anagen) phase to the resting (telogen) phase. Stress also alters immune balance, increasing pro-inflammatory cytokines like IL-6, IL-1β, and TNF-α. Not only can this worsen inflammatory skin diseases, but it can also trigger autoimmune reactions such as alopecia areata. In hair follicles, stress-related inflammation damages the hair follicles, leading to shedding and delayed hair regrowth. Further research also shows that stress also generates reactive oxygen species that damage DNA and proteins in hair and skin cells. With cortisol also reducing protective molecules like hyaluronan and proteoglycans, it promotes a weakened follicle structure and early regression of the hair cycle. Finally, with neurogenic and sensory signaling, this indicates that as the skin is rich in sensory nerves that release neuropeptides (substance P, CGRP, VIP, etc.) during stress, these chemicals can cause inflammation, blood vessel permeability, and stimulate immune cells, all of which negatively affect the hair follicle. This process, as previously mentioned, creates the cycle where stress sensations worsen inflammation, and so as visible symptoms increase, so does stress perception. 

One of psychodermatology’s biggest challenges is objectively measuring stress. However, this invites opportunities for further research to be done focusing not only on biochemical markers, but also on understanding how personal perception of stress shapes physical outcomes. Currently, researchers measure it with both subjective and biological indicators. Psychologically, scales such as the Perceived Stress Scale and Hospital Anxiety and Stress Scale assess stress levels. Biologically, stress is measured by looking at HPA-axis markers such as cortisol and inflammatory cytokines, as these show that the neuroendocrine and immune pathways are on. Other scales further note heart rate variability and behavioral observations in an attempt to fully measure a person's stress. 

To fulfill a holistic assessment, psychodermatology is forced to take on a unique approach compared to traditional dermatology treatments. Instead of creams or medication, therapy and stress reducers come into play. Therapy for stress management, for example, has been shown to reduce flare-ups in conditions like acne and psoriasis. Studies have shown that approximately 30% of dermatology patients exhibit psychiatric and psychosocial disorders, significantly contributing to the overall disability associated with dermatoses. Additionally, high rates of suicidal ideation have been reported, with 8.6% of outpatients with skin conditions. 

Psychodermatology reveals how deeply connected the mind and body truly are. Stress and emotion are seen as being intangible, but they manifest biologically through hormones, immune responses, and inflammation that can fundamentally alter the health of our skin and hair. Still, as much as science explains the mechanisms,  the field also challenges medicine to look beyond the physical, emphasizing the importance of treating patients as whole beings.

The Placebo Effect

It’s raceday. You need to set a new personal record by .5 seconds to make it to states. At higher levels, it's these precious milliseconds that matter most. Of course, there is an easier, guaranteed way to make that time. The first thing that comes to mind is probably PEDs, or performance-enhancing drugs. But, what if there was a way for similar results to occur without doing anything illegal? 

Then, a mysterious figure comes into view. He offers you a pill, saying that it will make you run faster. With the race about to start, you don’t even question if it’s legal and take it. So, you run, and are overjoyed when you see the time qualifying for states. Still, your heart feels heavy, so you go up to him to ask, “What was in that pill you gave me?” He responds, “It was just sugar”. The placebo effect occurs when a placebo—in this case, sugar—creates a beneficial effect, not due to the treatment itself, but because of the psychological belief in the treatment.

The placebo effect was first studied in the 20th century, during World War II. When morphine was starting to run low, American anesthesiologist Henry Beecher noted that wounded soldiers given saline—essentially salt water—instead of morphine, saw similar pain relief, simply because they believed that they were receiving a powerful drug. This phenomenon prompted deeper research into the mind’s ability to influence the body’s response to treatment. 

The placebo effect operates on expectation. When someone believes that a pill or treatment will improve their condition, whether it's for pain, anxiety, or even athletic performance, their brain often responds accordingly. Neurotransmitters like endorphins or dopamine may be released, physically changing how the body feels or functions. In sports, this physiological trick can translate into tangible performance improvements. Runners might shave off milliseconds, lifters might add extra reps, and fatigue might set in later than expected. All of this is due to the brain's belief in an edge that does not chemically exist. 

When placebos can have a surprising impact, they also raise ethical questions. Is it right to deceive someone, even if it's for their benefit? And how far can the placebo effect truly go? Obviously, you can’t sugar-pill your way to Olympic gold, but the belief that you can get better, faster, or stronger might just be enough to tip the scale in cut-throat situations.

In a world where the tiniest edge can make the biggest difference, the mind might be the most overlooked performance enhancer of all

Interestingly, some researchers are now studying open-label placebos, where people are told they’re receiving a placebo, yet still experience benefits. At first, this might seem counterintuitive, but it shows the profound impact of the mind-body connection. In sports, this could open doors to mental training methods that boost performance without violating any rules.  

In a world where the tiniest edge can make the biggest difference, the mind might be the most overlooked performance enhancer of all. Whether through traditional placebos or open-label versions, belief can sometimes be just as powerful as biology.  In competitive sports, where boundaries are strictly regulated, harnessing these effects through transparent, evidence-based methods, such as open-label placebos, could redefine the way we approach performance in sports. The effective use of placebos holds immense potential for the future of training and competition.

The Uncanny Valley

Credit: https://www.nytimes.com/2023/12/13/style/the-polar-express-hero-girl-tiktok.html

At first glance, the character above appears almost human—but something about her smile, her eyes, or her facial expression is odd. That unease isn’t just your imagination; it is the Uncanny Valley at work. This photo is from The Polar Express, a film often notorious for its hyper-realistic animation that lands uncomfortably between cartoon and human. Hopefully, you felt something was off—that’s the psychological effect at work. Holly, also called “Hero Girl,” is a lot more realistic than, say, a cartoon Superman. And yet, despite more realistic, she triggers more discomfort because she is almost—but not quite—human.

The Uncanny Valley was originally developed in 1970 by Japanese robotics engineer Masahiro Mori. At face value, this phenomenon might just seem like an instinct you have and nothing more, but there is a whole lot more. 

The process of analyzing human faces and emotions is complex, involving a network of brain regions like the fusiform face area (FFA) and amygdala, working together to interpret facial expressions and extract meaning for social interaction. The specific patterns of facial muscle activity that create emotional expressions have been shaped over millions of years. Three main ideas attempt to explain the origin of this effect.

The Uncanny Valley is not just a feeling you get in your gut when you look at something off—it’s the product of deeply-rooted psychological and evolutionary mechanisms

The evolutionary theory suggests that there was a point in history where evolution required slight deviations from human-like features to trigger discomfort; examples of this could be people who could be potentially dangerous or diseased individuals. 

Another idea is cognitive dissonance, defined as the mental discomfort felt when people hold attitudes or beliefs that conflict with their behaviors. In this case, when something looks human, people then subconsciously hold expectations of human-like behavior—when this expectation is not met, though, people may feel cognitive dissonance, consequently leading to a feeling of uneasiness. 

Finally, impaired empathy is the inability to understand or share the feelings of other people. Small cues such as facial expressions and body language are extremely important to human interaction and socialization. Similar to dissonance, when these boxes are left unchecked, it creates complications in our ability to truly connect—impaired empathy—adding to the sense of eeriness. 

The Uncanny Valley is not just a feeling you get in your gut when you look at something off—it’s the product of deeply-rooted psychological and evolutionary mechanisms. Our brains have spent millions of years being able to recognise human faces and to ring an internal alarm when something looks human but doesn’t feel quite right. From unnatural movements to abnormal reactions, these things disrupt our set of expectations, triggering discomfort. 

As AI and hyper-realistic technology become a growing part of our daily lives, we can see why this valley matters. With growing exposure to these almost human-like entities, it can blur the line between human and machine. The more we interact with “almost-humans,” the more the line between real and artificial grows thinner, challenging our very sense of what it means to connect.

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Masahiro Mori, “The Uncanny Valley,” IEEE Spectrum, 2005.

Nancy Kanwisher et al., “The Fusiform Face Area,” Journal of Neuroscience, 1997; Ralph Adolphs, “Recognizing Emotion from Facial Expressions,” Behavioral and Cognitive Neuroscience Reviews, 2002.

Mahdi M. Moosa and S. M. Minhaz Ud-Dean, “Danger Avoidance,” Biological Theory, 2010.

Ayse Pinar Saygin et al., “Predictive Coding and the Uncanny Valley,” Social Cognitive and Affective Neuroscience, 2012.

Angela Tinwell et al., “Perception of Psychopathy and the Uncanny Valley,” Computers in Human Behavior, 2013.