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Decision Fatigue in a Digital World

Decision Fatigue in a Digital World

Why understanding ego depletion and bounded rationality is essential for health comms clarity (3 of 4 in Clarity Series)

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Ruth Dale
Jul 17, 2025
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Decision Fatigue in a Digital World
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Ever sat staring at a screen and thought:

"I literally can't decide anything right now."

That’s not laziness.
That’s ego depletion. Your brain’s decision battery running flat.

If that’s you right now, skip to the end to grab your free Breathwork and regain clarity

fictional animals looking stressed with mobiles


What ego depletion feels like

During the COVID crisis, I was working in behaviour change marketing for Public Health England, supporting the government’s national marketing response to the unfolding events.

When I was there, the phrase “cognitive exhaustion” came up constantly.
Internal comms channels. On the news. In WhatsApp groups. With neighbours.

Everyone’s brain was fogged by uncertainty, and decision-making became hard.
So many decisions that were once handled by mental shortcuts were suddenly made conscious.

When to shop.
How to shop.
Can I walk the dog?
Can I leave the house?

(Where I live, the police even stopped people to check if they were local or a day tripper.)


In behavioural science, this feeling is called ego depletion.
It refers to the temporary state where your self-control and decision-making capacity deteriorate after sustained use (Baumeister et al., 1998).

So when we talk to our audiences, we must ask:

How depleted are they?

And the answer?

If they’re online more than six hours a day, chances are: very, very depleted.


Bounded rationality. The second layer.

Now let’s add another behavioural layer: bounded rationality.

Coined by Nobel Laureate Herbert Simon (1955), it means:

People want to make good decisions.
But they’re limited by time, mental energy, and available information.
So they make “good enough” choices with what’s left.

In Episode 1 of this Clarity Series, we asked:

Are we expecting people to behave as calm, logical decision-makers in a noisy, overwhelming world?

Bounded rationality says they can’t.
And your clarity means you stop expecting them to.


Clarity or pressure?

So today’s clarity question is:

Are you adding pressure to a depleted brain, or clearing the way for action?

Your audience isn’t ignoring your message because they don’t care.
They’re ignoring it because their decision-making power is maxed out.

If your message relies on a rational, calm audience, it’s in trouble.
Design for the real audience: tired, distracted, short on time, long on noise.

What helps?
Clarity. Always clarity.


First, a gift for you 🎁

Before we share the Change Card, please grab your free BrainFuel Breather below.

This is the third in our intro-to-breathwork series. Written by Sabine, a gifted breathwork facilitator and yoga teacher, it’s created especially for people who write for a living.

It’s five minutes. And it works.


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Audio playback is not supported on your browser. Please upgrade.

Enjoyed these ideas - there is more on this on Episode 74 of the BrainFuel Podcast
Digital Overload in a Digital World: Health Messaging vs. Bounded Rationality & Ego Depletion.
Search BrainFuel on Spotify, Apple.


Preview: Change Card 003

Ego Depletion and Bounded Rationality

Want to see what’s inside before upgrading? Here’s what this Change Card includes:

  • Three signs you’re assuming too much cognitive capacity

  • Three prompts to simplify your messaging

  • Three techniques to reduce friction in CTAs and copy

Examples from smoking, sexual health and vaccinations.


The Change Card is also available as a downloadable - so you can get using it immediately. And don’t forget you get free access to the Social Norms Mini-Training that is taking place on the 19th August 2025 when you upgrade for the year.

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© 2025 Ruth Dale
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