What is Mental Health? Part I

Mental Design Institute
8 min readAug 17, 2023

People are talking more about mental health recently, but we never hear an explanation of what mental health actually is because it’s really complex.

But, we all have to deal with the ups and downs of life — so better understanding what mental health is and how it works can help, especially during tough times.

That’s why we’ve developed a simple way to think about mental health.

Many people have found this explanation helpful and it’s consistent with scientific understanding of how mental health works.

We are a team of Harvard-trained mental health scientists and clinicians as well as designers with experience communicating complex ideas clearly.

This is Part I of a three-part series.

Part One: Emotions and the Body

If we’re going to talk about mental health, we have to start with emotions.

Emotions define our day-to-day experiences. While experts don’t always agree about how emotions work exactly, everyone recognizes emotions are something our body (which includes our brain) produces. In the first part of our series, we’ll explain that emotions are signals: automatic messages sent from our body.

1. Emotions Are Automatic Signals

Our bodies are always busy keeping us alive. Our hearts pump blood, our stomachs digest food, and our immune system fights invaders. All these processes are automatic — our bodies do them without us needing to make conscious choices or help in any way.

But sometimes the body needs our help, so it sends us a message. The feeling of being hungry, tired or having to pee are signals sent by our body in the form of sensations. These sensations are messages to eat, sleep or go to the bathroom.

Emotions are also signals sent by our bodies, just like feeling hungry or feeling tired.

These signals are automatic because we don’t choose when to feel them. For example, our body decides when we’re hungry or tired.

Emotions work the same way.

When something happens, we can’t choose what emotion to feel or how strongly to feel it.

Like, when we hear that a friend has died, we don’t get to choose our emotional reaction.

Instead, our body automatically sends an emotion — and it decides how strong the emotion is.

(This doesn’t mean we’ll feel this way forever, or that we can’t control how we respond. But we’ll get into that in a bit!)

2. Signals Push Us to Act By Making Us Uncomfortable

Many of the signals our body sends are uncomfortable sensations, like being hungry, tired or having to pee. These signals push us to act — to do something, like eat, sleep or go to the bathroom.

Negative emotions — like sadness, anger, and fear — also are uncomfortable sensations, which push us to act.

For example, fear is an uncomfortable sensation that pushes us to run away.

Anger might push us to yell or hit someone.

Sadness might push us to do nothing, maybe stay in bed all day.

3. The Uncomfortable Sensations Change How We Think

When we feel uncomfortable, our bodies further push us to act by changing how we think. Uncomfortable sensations actually make us think differently — they change our perceptions and beliefs about the world.

Think about being hungry at the grocery store. Everything looks delicious! Being hungry literally changes what food is appetizing and we buy things we wouldn’t buy if we weren’t so hungry! This changed thinking is our body pushing us to eat.

Emotions change how we think, too. Emotions are very convincing, and they can make us believe things about the world — and ourselves — that aren’t entirely true (or helpful). Here are some examples:

When we’re afraid, we might believe we’re in danger — even if there is nothing that could hurt us.

When we’re angry with someone, we believe they’re wrong — even if when we’re not angry, we admit they were right all along.

When we’re sad, we might believe that no one cares about us — even when a lot of people actually love us.

By producing uncomfortable sensations and changing how we think, emotions push us to make different decisions and see the world differently. And the stronger the emotions are, the more they change the way we think and see the world.

4. We Have Choices Over How We Respond to Signals But It Takes Effort

When hunger is pushing us to eat, we don’t have to eat. But, because hunger is pushing us to eat, resisting the push requires effort from us.

Likewise, we can resist the push of emotions — but it takes effort. And the stronger the emotion, the more effort it takes to resist its push.

For example, if we’re afraid of people judging us, the anxiety will push us to leave and it will take effort to resist the push and talk to people.

Or if sadness is pushing us to stay in bed all day — although we technically have a choice to get up, it can take a great deal of effort to resist the push from sadness.

In this example, the push of sadness is like a heavy weight pinning us to the bed. The stronger the sadness, the heavier the weight. When the push from sadness is like a 50-pound weight, getting out of bed takes a lot of effort.

But, when we’re clinically depressed, the push from sadness is like a 300-pound weight. Even with maximum effort, getting out of bed may be impossible.

Still, all emotions — even strong ones — change over time. Eventually sadness will fade, the push will be weaker and then it might be possible to get up.

All emotions come and fade. Fear can be a very strong push because it is the body’s way of pushing us away from danger. But, once we feel safe, the emotion and discomfort fades.

The push from anger can fade quickly, although the length of time for emotions to fade partly depends on how strong the push was to begin with.

The way we react to our emotions can help or prevent emotions from fading, which we discuss in Part III.

It’s hard for us to understand each others’ emotions because they’re invisible. Often, we assume the strength of everyone’s emotional reactions are the same as ours. So when a sad friend can’t get out of bed, we assume they are just not exerting enough effort. But we can’t know how strong others’ emotional pushes are.

The push of negative emotions is perhaps one of the hardest things to deal with in life. Negative emotions feel so uncomfortable — and they change our thinking so much — that it’s extremely difficult to resist their pushes.

5. Our Environment Affects Our Responses to Signals

The situation around us can make it easier or harder to manage pushes from emotions.

When we’re in a stressful situation, it activates emotions that push us and drain our energy. If we have another emotional reaction — like if someone yells at us — we have less energy to resist its push.

For example, if we’re already feeling sad and anxious when a boss points out that we’re late, we have less energy to resist a push from anger and so we lash out.

So, our ability to manage emotions depends on other emotions we are dealing with.

Our body will consistently send emotions if we live in chronically stressful circumstances — a difficult relationship, poverty, or a stressful job. The pushes from these emotions drain our energy and make it more difficult to do normal things.

Alternatively, the more positive things going on around us — supportive and stable relationships, financial security, work we enjoy — the more energy we have to manage new emotions that come up. We may still get angry when our boss points out that we’re late, but we have the resources to resist the push to lash out.

End of Part 1

So far, we’ve shown that:

  1. Negative emotions are signals — just like hunger — sent automatically by our body to push us to act by being uncomfortable sensations and changing how we think.
  2. Even though we do not have any choice in whether we receive these signals, we can choose how to respond to them, but resisting their push takes effort.
  3. Finally, the environment around us affects how much effort we have to put in to manage our emotions.

In Part II, we explore why we have emotions and what this means for our mental health.

Next: Part II— Understanding Emotions

And, if you’d like to read more articles like this, please consider donating to the Mental Design Institute here.

Mental Design Institute is a nonprofit organization creating simple, clear, and scientifically informed ways to better understand mental health. We aim to reduce stigma and empower individuals through education.

With editorial assistance from Maggie Millner