Are you afraid of spiders? Many of us are, and when confronted with one, we’ll have one of two responses - the first is fight- to spring into action and show that spider who runs the jungle. The second is flight- to run away in fear. This human response to perceived threats is aptly named the fight-or-flight response, and is the result of an interaction between our brain and endocrine system, an interaction called the - you ready? - hypothalamic-pituitary-adrenal axis*. For brevity’s sake, we call it the HPA axis.

Say you need to get a bunch of your friends—more than a quintillion of them, in fact—from one place to another to do an important job. Naturally, you’re going to need a creative way to get them there. Would you use a plane, train, or car? Maybe you’d need all of the above! This is exactly what the respiratory system does: it gets oxygen from the air, through the body, and all the way to the tissues to help the cells make energy from the food you eat. Then it needs to send the cells’ waste—carbon dioxide—out of the body. We call this process gas exchange. Fortunately, it gets a hand from your circulatory system and several clever modes of transportation to get the job done.

Welcome back to another Ask Dr. B. Today we’re talking about social psychology—that is, how your thoughts, beliefs, and actions are changed by interacting with others (and I don’t just mean things you do by yourself that you would be embarrassed to do in front of other people—like singing into your stethoscope in front of a mirror! Not that I do that….). Let’s get out of our heads and into the questions.

We can't see it, and usually can't smell it...but have you ever thought about the air you breathe? What's it made of, anyway? Is all air created equal? The lungs are the central organs of the respiratory system. They play a vital role in a wide variety of critical bodily functions that keep you alive and healthy. For example, the lungs, assisted by muscles of respiration like the diaphragm (located below the lungs) and the intercostal muscles (found between the ribs), are responsible for the body’s ability to breathe.

When an allergen enters your respiratory system, it can set off a false alarm that causes your immune system to mistake it for an invader. Recall from Adv. 6 that your immune system responds to viral invaders by creating antibodies[note for web design: link to Adv. 6materials]. The immune system does just that - it forms antibodies to fight the allergen, even though it’s harmless. Each time you encounter the allergen thereafter, the new antibodies alert the immune system, which responds by releasing histamine (Say it like this: HI-stuh-meen).Histamine is a hormone, and we remember from Adv. 8 what they do[note for web design: link to Adv. 8 materials]- they tell your cells to do stuff! In this case, they tell your cells to sneeze, cough, irritate your eyes, or make your nose run.

Let's take a look at how we’re affected by what  others  are thinking and feeling (or what we assume they’re feeling). This science, called  social psychology,  is the study of how our interactions with other people change the way we act and think. People have been writing about social psychology as far back as the ancient Greeks (and likely even further), but it was William McDougall who published   An Introduction to Social Psychology  in 1908, the first notable work on the subject written in English.  Since then, psychologists have been studying and naming various ways the speech, actions, and presence of other people affect our own - in obvious and in not-so-obvious ways.

You’re sweating, flushed, nauseous, and fumbling for words...is the flu coming on? No, it’s just time to talk about the “P” word: puberty. Are you worrying about how to bring up the topic with your pre-teen? It can be an awkward subject for both parents and kids, but understanding the science of what’s happening can help to put everyone at ease.

Hello, Adventurers! Today I’m answering your questions about the endocrine system—the system in your body that regulates all kinds of important functions inside of you. Your brain and other organs do this by sending out signals in the form of  hormones, which instruct parts of your body to grow, adjust temperature, process nutrients, and almost everything else that keeps you up and running. At any given time, your hormones might be telling you that you need to eat, take a nap, or put on a sweatshirt…mine are telling me to move on to your questions.

Our thoughts, emotions, and behaviors are all deeply connected. So connected, in fact, it’s sometimes hard to tell them apart. For instance, “I feel like I’m not good at math,” and “I feel like she doesn’t like me” are both thoughts, even though they use the word “feel.” Kind of confusing, right? Let’s take a closer look.

There’s no denying that humans are emotional beings. Everything we see, hear, or experience incites an emotional reaction, even if that reaction is sheer boredom. Sometimes this can feel exhausting, but it’s not without good reason -- emotions inform decision-making, and help us assess risk and prioritize needs. Emotions also help us communicate with and care for others, allowing us to create friendships and build communities.

You have over 600 muscles in your body. So many, in fact, that muscle makes up about half your weight. It may seem muscles take up more than their fair share, but they have good reason to make such a heavy claim to your frame: muscles are your body’s primary source of power. Whenever something inside you needs to move, chances are your muscles make it happen.

A muscle sprain or strain may sideline you to the couch. But while you’re resting up, do you ever wonder...what are my muscles doing right now? Your body has some clever gadgets to help you heal. While you’re catching up with your favorite show or re-reading a book, your muscles are calling on their own in-house repair team, which is always waiting in reserve to help you out in a pinch (or sprain).