Why Can't I Stop Overthinking? A Therapist Explains | Insights Wellbeing

I want to describe something, and you tell me if it sounds familiar.

It's late. You're tired. You've done everything right, brushed your teeth, put your phone away, and turned off the lights. And then your brain goes: "Hey, remember that thing you said at lunch three days ago? Let's replay it 40 times and figure out exactly how badly you messed up."

So you lie there. Running the same conversation. The same scenario. The same worry. Over and over. You know it's pointless. You know you're not solving anything. But you can't stop.

Or maybe it's not nighttime for you. Maybe it's the middle of a workday, and you've spent 45 minutes deciding what to eat for lunch because every decision feels like it has consequences. Maybe it's a text you sent two hours ago, and you've already checked your phone eleven times to see if they've replied.

If any of this sounds like you, hi. I'm Priya. I'm a Counselling Psychologist. And overthinking is probably the thing I work with most. Not overthinking as a hashtag. Not overthinking as a quirky personality trait someone puts in their Instagram bio. Overthinking is a real, daily, exhausting experience that makes you feel like your brain is working against you.

Because — in a way — it is. And there's a reason for that.

There's Actually a Part of Your Brain That Does This

Okay, I'm going to mention one slightly science-y thing, and then I'll make it simple.

Your brain has something called the Default Mode Network. Researchers call it the DMN. It's a group of brain regions that light up when you're not focused on a specific task, when you're resting, lying in bed, sitting on a bus, or just... being.

The DMN's job is actually really useful. It handles self-reflection. Planning. Processing experiences. Making sense of your day. It's the part of your brain that goes, "What did that conversation mean?" and "What should I do about that situation at work?"

Good stuff. Necessary stuff.

But here's what happens in people who overthink: the DMN doesn't know when its shift is over. It just keeps going.

A meta-analysis looking at brain scans of people who ruminate found exactly this: overactivity in the Default Mode Network is directly linked to the kind of repetitive, circular thinking that overthinkers know intimately. Your brain's reflection system gets stuck. It's like pressing "replay" on a song you didn't even like.

I explain it to clients like this: imagine your browser has 47 tabs open. Each tab is a different worry. Your brain keeps switching between them, but it never actually closes any of them. So it just... keeps running. Slowing everything down. Heating up. And you're sitting there wondering why you feel so mentally exhausted even though you "didn't do anything all day."

You did do something. Your brain ran a marathon. You just didn't go anywhere.

Why "Just Stop Thinking About It" Makes It Worse

I need to talk about this because someone has definitely said it to you. Maybe a parent. A friend. A partner who doesn't overthink and genuinely doesn't understand why you can't just... not.

"Just stop thinking about it."

If that worked, you would have stopped years ago.

Here's what's actually happening when you try to suppress a thought: your brain, in order to check whether you've successfully stopped thinking about it, has to think about it. It's called thought suppression rebound, and it's one of the most replicated findings in psychology.

Your brain treats "don't think about the presentation" as "definitely keep monitoring the presentation thought." The harder you try to push it away, the stickier it gets.

This is why I never tell my clients to "stop overthinking." It's like telling someone with a broken leg to stop limping. The instruction makes sense. It's just completely useless.

What I do instead is help them change their relationship with their thoughts. Which is a very different thing.

Three Kinds of Overthinking (Yours Is Probably One of These)

One thing I've learned from working with clients who overthink is that not all overthinking feels the same. And knowing which kind you do matters, because the fix is different for each.

The Replayer. You go back. Again and again. To something that already happened. A conversation. A mistake. A moment where you said the wrong thing or didn't say enough. You replay it, looking for what you should have done differently. But the replay never ends with relief. It ends with guilt, shame, or that knot in your stomach that just... sits there.

The Rehearser. You go forward. Into the future. Running simulations of things that haven't happened yet. What if I fail? What if they reject me? What if I say yes and it's the wrong choice? Your brain treats these simulations as if they're actually happening, which is why your heart races and your stomach drops even though you're just sitting on your couch imagining a scenario.

The Decider Who Can't Decide. You're stuck between options. Every choice leads to another "but what if." You research, you compare, you ask five friends, and you still can't choose. So you do nothing. And then you overthink about the fact that you did nothing.

Most of my clients have all three. But one is usually loudest. When I know which one is running the show, I know which therapeutic approach will actually help.

What I Actually Do With Clients Who Overthink

I'm going to skip the generic advice. You don't need me to tell you to go for a walk, drink chamomile tea, or journal your feelings. If that worked, you wouldn't be reading this at, let me guess, sometime past 11pm.

Here's what actually works in my sessions. These aren't tips. These are therapeutic tools I use with real clients, in real sessions, every week.

For the Replayer — we use CBT to catch the thought and examine it.

When your brain says, "I shouldn't have said that, they definitely think I'm stupid," we don't argue with it. We investigate it. What's the evidence for this thought? What's the evidence against it? What would you say to a friend who had this exact thought?

We're not replacing a negative thought with a positive one. We're replacing an inaccurate thought with an accurate one. "They definitely think I'm stupid" might become "I felt awkward, but I have no actual evidence that they think less of me."

That sounds like a small shift. In practice, it's everything. A meta-analysis across 83 studies confirmed that therapist-guided CBT produces measurable changes in how the brain processes threatening information. Your brain literally learns to respond differently.

For the Rehearser — we use ACT to change the relationship with the thought.

Instead of fighting the "what if," we observe it. One technique I use all the time: when the worried thought shows up, you add five words before it.

"I'm going to fail" becomes "I'm having the thought that I'm going to fail."

I know, it sounds too simple to work. But what it does is create a tiny gap between you and the thought. Instead of being inside the thought, you're looking at it. You're no longer the thought. You're the person noticing the thought. That gap is where freedom lives.

Over weeks, that gap gets wider. The thoughts still show up, but they don't run the show anymore.

For the Decider — we use scheduled worry time.

I know this sounds counterintuitive. But here's how it works: you pick a 15-minute window each day. That's your worry slot. When overthinking starts outside that window, you write the thought down and tell yourself, "I'll deal with this at 6 pm."

What happens? By 6 pm, most of those thoughts have already dissolved or feel way less urgent. The ones that remain get 15 minutes of focused attention instead of 15 hours of scattered attention.

It's not about suppressing thoughts. It's about containing them. Your brain learns: "I don't need to process this right now. There's a time for it."

For the one where it goes deep, we use Psychodynamic Therapy.

Sometimes overthinking isn't really about the thing you're overthinking about.

I had a client who couldn't stop replaying relationship conversations. Every text, every argument, every silence. We worked on it with CBT for a few weeks, and it helped, but the pattern kept coming back.

When we went deeper, we found this: she grew up in a home where saying the wrong thing had real consequences. Her overthinking wasn't a bad habit. It was a survival strategy she learned at age 8 that was still running at age 29.

Understanding that didn't magically stop the overthinking. But it changed how she related to it. Instead of "what's wrong with me," she started thinking "this makes sense given what I went through." That shift, from self-blame to self-understanding, is where the real healing started.

(Details changed for confidentiality, as always.)

When It's More Than Just "Overthinking"

I want to be honest about this part.

Overthinking by itself isn't a diagnosis. But when it's constant, when it's been going on for months, when it's affecting your sleep, your work, your relationships, when you can't remember the last time your brain felt quiet, it may be a symptom of something worth paying attention to.

Chronic overthinking is closely linked to generalised anxiety, depression, and OCD. That doesn't mean you "have" any of those things. It means that what you're experiencing has a name, it's well-understood, and there are structured ways to address it.

Not by trying harder. Not by being more disciplined. By working with a therapist who understands what's driving it.

Your Brain Learned This. It Can Unlearn It.

I want to end with the thing I wish someone had told me when I was studying psychology: your brain is not fixed. The neural pathways that drive your overthinking were built through repetition. Every time you replayed, worried, or spiralled, you deepened that groove. Your brain got really, really good at overthinking — because you practised it every day for years.

But neuroplasticity, your brain's ability to physically rewire itself, means those pathways can be redirected. Research confirms that structured interventions can reduce Default Mode Network overactivity by 30-40%, decreasing rumination and increasing present-moment awareness.

Your brain can learn to stop. But it needs structured help to get there. Not willpower. Not another listicle. Not a motivational quote on a sunset background.

It needs someone who can see the pattern, name it, and give you the tools to change it.

That's what I do.

If you've been living in your head for months or years, and nothing has made it stop, the exploratory call is where we start. 30 minutes. ₹500. Just a conversation to figure out what's going on and what might actually help.

Book an Exploratory Call →

Or text me directly: WhatsApp: +91 8123995406

Email: priya@insightswellbeing.com

Your brain has been running for long enough. Let's give it somewhere to land.

References

1. Zhou, H.X. et al. (2020). "Rumination and the default mode network: Meta-analysis of brain imaging studies and implications for depression." NeuroImage, 206, 116287. Read on PubMed →
2. Moshe, I. et al. (2021). "Digital interventions for the treatment of depression: A meta-analytic review." Psychological Bulletin (APA), 147(8), 749–786. Read the full study →
3. Santos, S.A. et al. (2025). "The Journey of the Default Mode Network: Development, Function, and Impact on Mental Health." Biology, 14(4), 395. Read the full review →
4. Svanishvili, G. (2025). "Real-Time Brain Feedback Reveals the DMN's Role in Creativity and Idea Formation." Premier Journal of Neuroscience, 2, 100006. Read the full study →