Subtitles section Play video Print subtitles Did you know that astronauts in space have a hard time communicating without words because their weightless bodily fluids make their faces all puffy and hard to read? Have you heard that Botox can actually improve your mood, and not by smoothing wrinkles but actually by easing depression? Or that this "come here" gesture is common in the US but is considered so rude in the Philippines that it could actually get you arrested. Yeah. All true! Emotions and the ways we express them are strange and powerful things. And emotions aren't just ephemeral psychological phenomena, they affect our bodies and our health. Because so many emotions have a certain contagious quality, our feelings and the behaviors they drive also affect the minds, and bodies, and health of those around us. This is true whether your emotions of the moment are of the feel-good variety. Or not. The powers of both positivity and negativity are stronger than you may know. Lots of studies have shown that people with a positive outlook on life tend to live longer, more fulfilling lives than their mean and grumpy neighbors. Fear, anger, and other more difficult emotions and how we handle them are pretty closely related to this thing called stress. And stress is so powerful that it can straight up kill you in any number of ways, given the right opportunity. For better or worse we spend a lot of our lives swirling around like leaves on the winds of competing emotions. Before we can hope to harness these feelings, we first have to understand them. [Intro] What do you think this person is feeling? How about him? And her? What about this one? It's not really hard to tell, is it? Most of us are better than we think at reading non-verbal cues and subtle expressions. The understanding among some, but not all, psychologists, like emotion expert Paul Ekman, is that facial expressions are culturally universal. So a Greek, Britain, American, Samoan, or Nigerian would all be able to discern the same basic emotions; happiness, sadness, disgust, anger, fear, and surprise, just by looking at your face. And our expressions don't just communicate emotions. According to the Facial Feedback Hypothesis, they can help regulate our emotions, too. The act of smiling broadly, even if you aren't happy, can actually lift your mood just as scowling can lower it. This is how, bizarrely enough, a recent randomized controlled clinical trial suggested that a little Botox injection in the forehead might actually lessen depression. 'Cause it's apparently hard to feel down if your frowny muscles are frozen. Of course whether your face is paralyzed or not, some people are better at reading your emotions than others. For example, introverts are usually better at interpreting people's feelings, while extroverts are often better at expressing them. And you've probably heard embarrassing stories or even experienced first-hand how different cultures express emotions through particular gestures that are far from universal. For example, in the United States, this is a peace sign, but you don't want to flip it around in the UK. And the iconic thumbs up gesture means "good job" in many cultures, but if you toss that thumb around in Greece, well let's just say you won't make any new friends. But of course emotions involve a lot more than making faces and hand gestures, they're also about our conscious experience of what we're feeling. So how do we actually feel all these feels, and how many different emotions are there? Back in the 1970s, American psychologist Carol Izard identified ten distinct basic human emotions present from infancy on. They are: joy, surprise, sadness, anger, disgust, contempt, shame, fear, guilt, and interest or excitement. Others have since suggested that "pride" should be added to that list, and still others believe that love should be classified as a basic emotion as well, but Izard has argued that these and other emotions are just familiar combinations of the classic ten. Today, some psychologists describe our emotional experience as using a 2-dimensional model. The idea there is that any of the emotions you might feel while, like, reading Harry Potter or something are expressed on a spectrum, and as a combination of valence, roughly speaking "good" or "bad", and arousal--excited or not excited, basically. So if you're feeling both really excited and super positive when Harry finally bested Voldemort, you could say you were elated. On the other hand, if you're at that part in Deathly Hallows when Harry, Ron and Hermoine are just sort of wandering around on the lam in a heavy mood, maybe your emotions fell more on the opposite side of the spectrum. In this instance, feeling depressed might be a combination of negative emotion and lack of excitement. So potentially every emotion can fall in degrees on this 2-dimensional scale. Like being terrified means you're more frightened than if you're just scared, just as being enraged is a more extreme form of anger than simply being mad. These polarities--positive versus negative, high arousal versus low arousal--affect our psychological states, and therefore our bodies as well. Because, you'll remember that what is psychological is ultimately biological. And when it comes to the physical effects of our emotions, it pretty much goes the way you might expect. Happiness is helpful while chronic anger or depression makes us vulnerable to all kinds of problems with health and well-being. The good news is that if we're angry or sad, we often over-estimate the duration of our bad moods and under-estimate our capacity to adapt and bounce back from traumas, even if things feel hopeless, depressing, or stressful in the thick of it. And we've all experienced stress before, sometimes on a daily or even hourly basis. Much like anger or joy, stress can slowly build and simmer, or it can strike suddenly and with great intensity. And yeah, stress, certainly the chronic or extreme type can be bad for your health, but defining stress is trickier than you might think. Psychologists would define stress as the process by which we perceive and respond to certain events, or stressors, that we view as challenging or threatening. In other words, stress isn't technically an emotion, it's more of a reaction to a disturbing or disruptive stimulus. And our reactions stem in part from our appraisal of that stimulus. A person can either roll with, or get worked up about a missed flight, an increased workload, or a strange thump in the house. These external stressors typically fall into three main categories: catastrophes, or unpredictable large scale events like war, natural disasters and terrorist attacks; significant life changes, things like moving, having a child, losing or getting a job, or the death of a loved on; and then just everyday inconveniences like getting caught in traffic, running late, or feuding with your roommates. Any of these stressful events, big or small, even the good things, can fire up your sympathetic nervous system and trigger that old fight or flight response. In this way, it's important to understand that stress is ultimately natural. You experience it for a reason and a bit of short-lived stress can actually be a good thing. It can make you active and alert when you need to be, like an upcoming chemistry test might be stressing you out, but that might help you find focus so you can dominate that thing. And in your body, moderate stress can kick the immune system into action to do things like heal wounds, and fight infections. It does this by triggering the release of stress hormones like adrenaline and cortisol. These chemical messengers are what get your organ systems to respond the way you need them to when you're getting charged by a bear, or focusing really hard on the gas law for your chemistry test. But to also why chronic stress can really wreck a body and mind, research has shown that abused children have a high risk of chronic disease and people suffering from post-traumatic stress disorder, PTSD, which we'll talk about in an upcoming episode, experience higher rates of digestive, respiratory,