The reason: decision fatigue. Taking tests requires a series of complex decision-making to choose the right answer, and the longer students spend doing that, the more exhausted their brains become. Just as you might start running slower and paying less attention to your form toward the end of a hard run, your brain will begin processing decisions slower and make more mistakes as it becomes more fatigued.

What Is Decision Fatigue?

“The more decisions you have to make, the more fatigue you develop and the more difficult it can become,” explains Dr. Lisa MacLean, a psychiatrist and chief wellness officer at Henry Ford Health System. The human brain is like a muscle. It gets tired of working just like legs might get tired of running. As your brain reaches the point of exhaustion, you might find yourself experiencing some of these symptoms:

Difficulty thinking clearly or staying focused on the decision Feeling easily overwhelmed Headaches, upset stomach, and other physiological symptoms of stress Irritability, frustration, and short temper Dissatisfaction with all available choices

In that stressed and tired state, you’re liable to make impulsive, short-sighted decisions—or you might procrastinate and avoid making a decision. Some might find themselves paralyzed with indecision, unable to make any choice at all.

As the studies of judges, doctors, and school students show, anyone can experience decision fatigue, but it usually happens after making a lot of really complex decisions—like answering increasingly challenging academic questions on a test or deciding the fate of a prisoner asking for parole. For people with ADHD, on the other hand, decision fatigue can become a near-constant state, even on days when they aren’t making any especially tough decisions. One possible explanation is that the vast majority of those 35,000+ decisions we make each day involve something called cold cognition.

Hot vs. Cold Decisions

When the choices are emotionally charged enough, we can act on instinct and intuition rather than consciously and methodically processing information. Intuitive “hot” decision-making like that is exactly where people with ADHD usually excel. I have often noticed (and used to find it strange) that while I can get easily overwhelmed in typical situations, I tend to feel calmer, and my thinking seems clearer in moments of crisis. Once, while I was still learning to cook, I accidentally started a grease fire in my oven. I’d spaced and forgotten to cover the ribs to prevent splatter. When my non-ADHD roommate saw the flames, she froze in panic, unable to figure out what to do. Meanwhile, I sprang into action. I sent a friend out to find a neighbor with a fire extinguisher since we didn’t have one, tasked my panicked roommate with going outside and calling the fire department, all while I went to get our very frightened cat into his pet carrier so we could all get away from the fire until it was extinguished. Within a few minutes, we’d secured a fire extinguisher, and the situation was under control without any serious injuries or damage. I then ordered a fire extinguisher to keep in our apartment for any future emergencies. We’re not putting out literal fires most of the time, though. Most days, we’re making thousands of emotionally-neutral decisions like what to eat, what to wear, what to watch on TV, and how many bagels to bring to the morning meeting. If you’re making 35,000+ difficult-for-you decisions every single day, you’re bound to feel fatigued pretty often.

How Decision Fatigue Affects Different Areas of Life

Struggling with frequent decision fatigue can make just about every part of your life more challenging. In your personal life, decision fatigue can put a lot of strain on your relationships. If you tend toward impulsivity, you might not think through the things you say and end up saying something inconsiderate, offensive, or just not helpful. It can also lead to impulsive actions—like ordering that extra round of shots when you should have just called it a night or agreeing to foot the dinner bill even though you’re already over budget. Impulsive decisions in the workplace can lead to mistakes and oversights in your work. The same is true for homework and class assignments if you’re a student. Avoidance and procrastination can be just as harmful. If you often procrastinate or avoid giving a firm answer to friends about plans, they might assume it’s a lack of interest rather than decision fatigue. When your boss asks if you’d like to take on a new project, waiting too long could both signal a lack of ambition and hurt your chances of career advancement. Decision fatigue can even impact your life indirectly. In this more irritable and frustrated state, you might snap at your partner over minor non-issues or have an outburst at work. If you’re prone to headaches or stomach aches when stressed, frequent decision fatigue might mean frequent aches and pains.

How Can Those With ADHD Cope with Decision Fatigue?

The good news is that decision fatigue is a lot like the fatigue you feel after a hard workout. With enough rest, it will go away on its own. Moreover, if you’re experiencing chronic decision fatigue, it’s likely a sign that you’re overworking your brain and need to look for ways to reduce the load. Here are a few strategies that can help you reduce cognitive load and get the rest that your brain needs.

Use Routines to Eliminate “Cold” Decisions

Sticking to a routine might sound like one of the most impossible things you could ask a person with ADHD to do, but when it comes to these everyday “cold” decisions we have to make, it can be easier to keep a routine than it is to overcome the paralysis of decision fatigue. For example, I used to agonize over deciding what to eat—three meals a day, and they all have to be different? Are you kidding me? You can eliminate that problem by making a meal plan for yourself. For best results, keep it simple. You don’t really need seven different breakfasts, lunches, and dinners each week. You can get away with picking two or three dishes for each meal and then just alternating days. In my case, I eat the same breakfast every day: fruit with yogurt. The only thing that changes is the type of fruit I add. It might sound monotonous, but its routine has made it so much easier to get myself to eat breakfast consistently because I don’t have to think about it. Before I started meal planning, I’d often skip meals entirely and wouldn’t manage to feed myself until late at night. Now, it’s as automatic as making my coffee in the morning. For lunch and dinner, I usually pick two recipes for each week from a list of go-to recipes that I like and know how to make. In most cases, they’re also recipes that I can easily make in bulk to reheat leftovers for the next day or two.

Give Yourself More Time

In the study of Danish students mentioned earlier, researchers found that, just like with physical exercise, rest can help reenergize your decision-making functions. After a 20- to 30-minute break in the school day, Danish students showed a 1.7% average increase in test performance, enough to compensate for nearly two hours of cognitive strain. Sometimes, the best thing you can do is indulge the urge to procrastinate. If the decision is a big one and you’re too exhausted to give it the consideration it needs, it’s better to put it off until you’re in a better headspace. The caveat: you can’t procrastinate forever. Instead, block out a specific time in your calendar to make that decision. Then, use that extra time you gave yourself to actually rest. Too often, people with ADHD use the time spent procrastinating to agonize over all the things they should be doing at that moment. Try to shut that critical voice out so you can relax during this break. Go for a walk outside. Take a long bath with your favorite scented candles and a glass of wine. Lay on the floor and listen to your favorite chill-out playlist. Do something that you enjoy and that reinvigorates you. That way, when you do come back to the decision, you’re coming back refreshed and energized.

Make the Most Important Decisions First

Every week, you can start your Sunday morning by listing the biggest decisions you know you have to make in the coming week. Is a coworker going on leave, and you expect your boss might ask you if you’re willing to shoulder some of their tasks? Do you need to pick a topic for an essay due next week? Are you planning to buy a new laptop or make another large purchase? Use that Sunday morning (or whatever your free, least stressful day is) to make those decisions so that when the everyday choices of the week wear you down, you know that your fatigue at least won’t impact the bigger decisions. Follow Now: Apple Podcasts / Spotify / Google Podcasts

Talk Through It Out Loud

If you have ADHD, your brain is probably loud. You might start your thought process about what show to watch with every intention of arriving at a decision by the end of it. But somewhere along the way, you find yourself needing to know who the tsar of Russia was in 1679. Three hours of a Wikipedia wormhole later, you don’t have time to watch anything because you have to go to bed. Sometimes, talking through your decision aloud can help cut through the noise and keep you on track. For example, when figuring out a show to watch, you might say what your main options are and talk through why you do or don’t want to watch each one.

When All Else Fails, Just Flip a Coin

Some decisions need to be made on the spot, like whether to say yes or no to the friend that just invited you out for a drink or which dish to pick from a menu at a restaurant. In these cases, when it’s not a major life decision and you can’t afford to procrastinate, just let random chance decide. Flip a coin and just go with what it tells you. “Should I get the chicken nuggets?” No. “Should I get the bacon cheeseburger?” Yes. You’re done. Similarly, you can crowd-source these decisions in some cases. Don’t know what cocktail to order at a bar? Just ask the bartender to make you their favorite one. Don’t know which sheets to put on the bed? Text a friend and ask them to pick a color.  As long as the consequences aren’t life-altering, it’s better to save your brain the effort by leaving it up to chance.