Stress has a reputation problem. We talk about it like it’s something we should simply manage better, like it’s a personal failure rather than a biological response. In academia, especially, stress seems to be embedded in the job description. It’s listed alongside tasks like “read papers” and “occasionally question life choices.” But stress isn’t just a feeling; it’s a physiological process that changes how our brain functions over time. Here’s something important to remember: your brain is not working against you. It’s trying to protect you!

Can it be overprotective at times? Yes. Can it not distinguish between being chased by a bear and receiving an email from your supervisor? Also, yes. Let’s talk about what actually happens to your brain under stress!

1. The Stress Response: Your Brain’s Emergency Mode
2. The Amygdala becomes More Reactive (a.k.a Everything Feels Like a Big Deal)
3. The Prefrontal Cortex Goes Offline (Your Brain’s CEO Has Left the Chat)
4. The Hippocampus (Your Memory Centre) Takes a Hit
5. Your Brain Starts Prioritising Short-Term Relief
6. Stress Slowly Becomes Your “Normal”

1) The Stress Response: Your Brain’s Emergency Mode

When you experience stress, your brain activates a system designed to keep you alive. The amygdala is the brain’s built-in alarm system that detects potential threats and signals the hypothalamic-pituitary-adrenal (HPA) axis. This leads to the release of stress hormones like cortisol. This is helpful in the short term! Your focus sharpens. Your reaction time improves and you become more alert! Basically, your brain goes into “lock-in” mode.

This is why sometimes stress can improve performance. But here’s the issue. Your brain doesn’t really understand the difference between

1. Being chased by a lion
2. And having three deadlines, a lab meeting, and a passive-aggressive email

So, it responds to both in the same way. When this system is activated constantly, your brain will never really get the memo that it’s safe to relax.

Further reading

https://journals.physiology.org/doi/full/10.1152/physrev.00041.2006?rfr_dat=cr_pub++0pubmed&url_ver=Z39.88-2003&rfr_id=ori%3Arid%3Acrossref.org

2) The Amygdala becomes More Reactive (a.k.a Everything Feels Like a Big Deal)

With prolonged stress, the amygdala becomes more sensitive. Meaning, your brain becomes quicker to detect “threats,” even when it’s something simple like

• An email notification
• A meeting invite
• Or someone saying, ‘can we have a quick chat’ (which let’s be real, it’s never really quick)

Over time, this can make you feel more anxious, reactive, and easily overwhelmed. Stress causes the amygdala to become hyperactive, triggering fight or flight. Acute stress causes the amygdala to bypass the rational prefrontal cortex, resulting in immediate, intense, and often irrational emotional reactions. Essentially, your brain has turned up the alarm system. Which is helpful if you’re in danger. Less helpful if all you want to do is write a methods section.

Further Reading

https://www.nature.com/articles/nrn2639

3) The Prefrontal Cortex Goes Offline (Your Brain’s CEO Has Left the Chat)

The prefrontal cortex is responsible for decision-making, planning, and rational thinking. Basically, your brain’s CEO. Under chronic stress, its activity is reduced. Stress switches the brain from “top-down” control (rational, PFC-driven) to “bottom-up” control (reflexive, amygdala-driven). This causes the brain to focus on fearful responses. So, when you’re under stress, you might:

• Struggle to focus,
• Procrastinate
• Find yourself in a deep YouTube rabbit hole about something completely unrelated

It’s not that you’ve lost discipline. It’s that your brain has decided that surviving is more important than productivity. Which is great in theory, but not ideal when your survival depends on submitting that report!

Further Reading

https://pmc.ncbi.nlm.nih.gov/articles/PMC2907136/#:~:text=Abstract,of%20stress%20on%20the%20PFC.

4) The Hippocampus (Your Memory Centre) Takes a Hit

The hippocampus plays a key role in learning and memory. Chronic stress, especially prolonged exposure to cortisol, can affect how well it functions. The elevated cortisol causes neuronal shrinkage, inhibits new neuron growth, and reduces overall volume. As the hippocampus is crucial for memory, structural changes in this area due to stress lead to cognitive deficits such as difficulty forming new memories. This makes it harder to:

• Remember what you just studied
• Retain new information
• Recall details when you need them

If you’ve ever said to yourself, ‘I literally read this yesterday, why do I remember nothing?’ Stress might be involved. Your brain isn’t being lazy; it’s just prioritizing survival over storing detailed notes about a paper you read at 11 PM.

Further Reading

https://pmc.ncbi.nlm.nih.gov/articles/PMC4561403

5) Your Brain Starts Prioritising Short-Term Relief

When stress is prolonged, your brain shifts toward behaviors that provide instant gratification, often biasing toward short-term rewards and habit-driven responses. This might look like:

• Procrastination
• Doomscrolling
• Reorganising your desk instead of doing work
• Or suddenly deciding that now is the perfect time to start deep cleaning your room

This may look like a lack of discipline from the outside. But from a neuroscience perspective, it’s your brain going: “We are overwhelmed. Let’s do something that feels easier right now.” The problem is that short-term relief often leads to long-term stress. This creates a cycle of stress -> avoidance -> more stress -> repeat.

A classic. Not a helpful one. But a classic.

6) Stress Slowly Becomes Your “Normal”

One of the most subtle effects of chronic stress is adaptation, sometimes referred to as allostatic load. This is the cumulative wear and tear on the brain and body. Your brain adjusts to the level of stress you experience regularly. Which means over time, being constantly stressed can start to feel… well… normal!

You might think:

• “This is how everyone in academia feels’
• “Everyone else is coping just fine.”
• “I just need to push through”

Meanwhile, your brain is running a full-time emergency response system in the background. This is why burnout often feels like it comes out of nowhere. It doesn’t. It just finally becomes too loud to ignore.

So what can you do?

1) Break own tasks

• Big tasks = big stress
• Small, clear steps = manageable

Instead of: “Write report,” try:

• Open document
• Write one paragraph
• Outline the next section

2) Protect sleep

Sleep is when your brain resets stress systems. Without it, everything is harder.

3) Reduce decision fatigue

The more decisions your brain has to make, the more overwhelmed it becomes. Simplify where you can: plan your day, have a rough routine, and remove unnecessary choices. Your brain will thank you.

4) Create Clear End Points to Your Day

If work never ends, your brain never switches off. Even a small ritual, closing your laptop, going for a walk, changing environment, can signal that it’s time to stop. Otherwise, your brain is still working… just with worse focus.

5.) Lower the Intensity, Not Just the Hours

Sometimes it’s not about working less, it’s about working less chaotically. Fewer tabs open. Fewer distractions. More focused blocks. Calm work is very underrated.

Final Thoughts: Your Brain Is Not the Problem

Stress changes the brain, but not because your brain is failing. It changes because your brain is adapting to what it thinks is a high-pressure environment.

The good news?

The brain is adaptable in both directions (neuroplasticity). With reduced stress, many of these changes can partially reverse over time. When stress is reduced, many of these changes can improve over time. So if you’re feeling overwhelmed, unfocused, or stuck, it doesn’t mean something is wrong with you; it means your brain has been working overtime.

And maybe, it deserves a break before it starts sending you even more “urgent” notifications.