Why You Overthink? You May Have a Highly Sensitive Nervous System
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Why You Overthink? You May Have a Highly Sensitive Nervous System

Louise W Lu

Written by

Louise W Lu, PhD, MPH, BMLS

Alexandra V Goldberg

Written/Reviewed by

Alexandra V Goldberg, Registered Dietitian

In the first four articles of this series, we explored the biological roots of anxiety step by step:
From “Anxiety Doesn’t Speak — It Hides in the Body” where we identified the earliest physical warning signs,
to “Anxiety Is Not Just in Your Mind: When the Brain Forgets to Turn Off the Alarm” which explained how the nervous system gets stuck in “high alert,”
then “From Anxiety to Anxiety Disorder: When the Brain Turns Fear Into Habit” where we saw how anxiety becomes a learned loop,
and finally “Why Some Brains Can’t Let Go of Anxiety: Genes, Childhood, and Neural Memory” which revealed why some people are more vulnerable to anxiety than others.

In that last article, we discussed how certain brains are naturally more reactive— and how early-life stress and lifestyle rhythms can further train the nervous system to “hold on” to tension as if it were a habit.

So if you often find yourself easily tense, easily affected by others’ emotions, or easily overthinking— does that mean you’re weaker than others? Or does it mean your brain simply works differently?

In fact, it’s the opposite— you may belong to the Highly Sensitive Person (HSP) group, a natural neurobiological trait, not a flaw.

Think about yourself:
A single offhand comment from someone can stay in your mind all day;
a movie scene or song can instantly move you to tears;
crowded environments drain you quickly;
and you can sense emotional shifts in others almost immediately.

If these feel familiar— then this article is written for you.

In the following sections, we’ll dive into:
What exactly is High Sensitivity (HSP)? Why are HSPs more prone to anxiety?
And most importantly—how sensitivity can become strength, not suffering.

 


 

Ⅰ. What Are Highly Sensitive People (HSP)?

High Sensitivity (Highly Sensitive Person, HSP) is not a psychological disorder— it is anatural neurological trait, a kind ofhigh-resolution emotional and sensory system that makes you experience the world more vividly than most people. Research estimates that about 15%–20% of the global population are HSPs— which means roughly 1 out of every 5 people is highly sensitive.

Psychologist Elaine Aron describes HSP traits with the “DOES” model:

D: Depth of Processing
Your brain naturally processes information more deeply.
A conversation others forget in minutes may replay in your mind for hours;
before making decisions, you automatically analyze details and possible outcomes.
This isn’t overthinking—it’s your brain working in its “deep processing mode.”
O: Overstimulation
You are more sensitive to noise, crowds, bright lights, and busy environments.
Shopping malls, gatherings, or loud spaces drain your energy quickly;
when overstimulated, you may feel tired, tense, or experience a racing heartbeat.
It’s not weak stress tolerance—it’s a faster-responding nervous system.
E: Emotional Reactivity & Empathy
Your emotional system is more “three-dimensional” and “high-definition.”
Movies or music easily move you to tears; when someone is sad, you feel it in your chest too.
You don’t merely observe emotions—you absorb them.
This comes from stronger mirror-neuron activity.
S: Sensitivity to Subtleties
You notice things others miss.
A half-second change in tone, a subtle facial shift, or a shift in atmosphere— you pick it up instantly.
You’re not “too sensitive”—your internal dial is simply set to a finer frequency.

If you often feel like you “think too much, get tired easily, or are easily affected,” remember: this is not a flaw—it’s ahigh-precision brain system at work.
It gives you insight, creativity, and empathy. But without proper protection, high sensitivity can also make you more prone to anxiety.

Illustration of HSP brain features
Illustration: Highly sensitive brains react more quickly, intensely, and deeply to emotional cues, environmental changes, and subtle details.

 


 

Ⅱ. Why Are Highly Sensitive People More Prone to Anxiety?

Being a Highly Sensitive Person (HSP) is not the same as having an anxiety disorder. But the HSP brain does have several natural traits that make it easier to enter stress cycles—and harder to fully recover from them. This isn’t weakness. It’s a nervous system that operates in “high resolution” with a much higher input sensitivity.

1️⃣ A More Reactive Amygdala: Faster Threat Detection

The amygdala evaluates danger. In HSPs, it is more easily activated:
Imagine you’re in a meeting and your boss frowns or uses a slightly colder tone. Others may simply think, “He’s tired today,” but your brain is already running in the background:
“Did I present poorly?”
“Did I say something wrong?”
“Will this affect my performance review?”

Before you finish thinking, your body reacts first— tight chest, faster heartbeat, sweaty palms. Outwardly you’re still listening calmly, but internally, you’ve entered a mini emergency mode.

2️⃣ Deeper Prefrontal Processing: More Likely to Overthink

HSPs naturally process information more deeply:
What others forget instantly, your mind automatically expands into multiple possibilities. This gives you insight—but also makes you vulnerable to getting stuck in thoughts.

Example: A friend cancels your meetup with a short message:
“Feeling a bit tired today. Let’s do another time.”

Most people think: “Ah, she’s tired.”

But your brain might begin a full storyline:
“Did I say something wrong last time?”
“Maybe she doesn’t want to see me but feels bad saying it.”
“Did I misread the relationship?”

Deep processing is a strength— but when too much information + too much emotion come together, your brain becomes like a computer with too many tabs open: slowing down, overheating, and resisting shutdown.

3️⃣ Stronger Empathy Circuits: Absorbing Others’ Emotions

HSPs have more active mirror neurons, making them feel others’ emotions as if they’re their own:
When someone is anxious, you feel your own chest tighten. When someone is sad, you feel a lump in your throat. Every emotional “resonance” is also a physiological stress response.

Example: In an elevator after work, a colleague sighs and says, “I am so exhausted lately.”

On your way home, your mind won’t stop:
“Is she going through something serious?”
“Is work overwhelming for her?”
“Should I be helping?”

By the time you get home, you feel drained— not because something happened to you, but because you’ve involuntarily “carried” an emotional load that wasn’t yours.

4️⃣ Slower Nervous System Recovery: Stress Accumulates Easily

The HSP nervous system is like a high-sensitivity microphone:
It picks up more detail, feels emotions more intensely, and needs more recovery time. When stimulation is continuous, and rest is insufficient, anxiety becomes cumulative.

At work, you absorb every tone, expression, and subtle shift in atmosphere. You notice coworkers’ stress, your boss’s mood, clients’ reactions— and your brain logs it all.

After work, others unwind quickly. But you may still be replaying things:
“Did I say that correctly?”
“How should I prepare for tomorrow’s meeting?”

Your body may be sitting on the couch, but your nervous system is still on the battlefield of the day.
When this pattern repeats daily, anxiety stops being an episode—it becomes a constant background noise.

In short, high sensitivity does not cause anxiety—
but it creates a nervous system that is easily triggered and struggles to fully “turn off the alarm.”

In today’s high-stimulation, high-pressure world, HSPs are more likely to move along the path: Tension → Overload → Anxiety → Mental & Physical Exhaustion.

Neural mechanisms explaining why HSPs are more prone to anxiety
Illustration: HSPs show stronger amygdala activation, deeper prefrontal processing, and heightened empathy—creating a neural system more easily triggered by stress and slower to recover.

 


 

Ⅲ. When Sensitivity Meets the World: Information Asymmetry & Real-Life Conflicts

The challenge for Highly Sensitive People (HSP) is often not that they are “too sensitive,” but that their brains naturally receive far more layers of information than the average person around them. This creates a very common yet easily overlooked phenomenon— information asymmetry.

Most people receive just 1 layer of information.
HSPs receive 5 layers.
But everyone is communicating based on “the same message.”

This is why HSPs may feel uneasy, misread others’ intentions, or end up carrying more emotional load in relationships and workplaces. Your brain simply sees a world that is richer and more detailed than others realize.

🔹 Example 1: A Highly Sensitive Dad vs Non-HSP Family Members

During dinner, a family member casually says: “You seem a bit off today.”

For most people, this is just concern.
But for a sensitive father, it carries multiple layers:
“Did I disappoint them?”
“Did I not help enough today?”
“Are they hinting that something I did wasn’t good?”

The family gave only the surface-level message, while the HSP brain picked up emotional tone, micro-expressions, and subtle cues— naturally creating two different “realities.”

🔹 Example 2: A Single Sentence From the Boss

During a meeting, the boss says: “We’ll take a closer look at this part next time.”

Most people interpret it as: “We ran out of time today—let’s continue later.”

But an HSP’s brain instantly starts multithreaded processing:
“Did I not do this well enough?”
“Is the boss unhappy?”
“Do I need to redo everything tonight?”

Same sentence, completely different levels of complexity. This mismatch is why HSPs are more prone to anxiety loops.

So sensitivity is not a weakness— it is a neural pattern of high input → high emotional resonance → deep internal processing.
But in a fast, overstimulating modern world, your brain receives too much and gets too little recovery time— making tension, overload, and anxiety much more likely.

Comparison between typical and highly sensitive nervous systems
Illustration: Typical nervous system (left) vs Highly Sensitive nervous system (right), showing differences in stimulus input layers.

 


 

Ⅳ. How to Protect a Highly Sensitive Nervous System?

High sensitivity (HSP) is not a weakness—but without proper protection, in an era full of “invisible noise,” the brain can easily shift into overload → tension → anxiety.

The “noise” here does not refer to sound alone, but to all kinds of stimuli that keep the nervous system running nonstop: emotional noise, information overload, social undercurrents, others’ expectations, and even the red notification dots on your phone. Most people are not aware of these background signals, but an HSP brain receives, analyzes, amplifies, and then stores all of them.

The good news: with the right strategies, a highly sensitive brain can operate with stability, strength, and deep insight. The following five directions are the most essential protections for HSPs:

1. Set Emotional Boundaries — Reduce Absorbing Others’ Emotions
Highly sensitive individuals often internalize others’ emotions as their own. Learning to distinguish “this is my feeling” from “this belongs to someone else” can greatly reduce nervous system load. A simple practice: when you start feeling tense for someone else, ask yourself— “Is this really mine to carry?”
2. Rhythmic Restoration — Create a ‘Charging Station’ for Your Nervous System
HSP brains take in too much, so they need more structured output and recovery: consistent sleep, morning light exposure, and pockets of quiet time. Adequate sleep is especially important—it helps restore cortisol rhythm and shifts the brain from “stress mode” back to “repair mode.”
3. Reduce Environmental Stimuli — Give Your Brain ‘Noise Reduction’
HSPs are particularly sensitive to sound, light, and crowds. Quiet environments, soft lighting, and reduced social demands can significantly reduce overstimulation. This is not avoidance—it’s providing a healthy operating environment for a sensitive nervous system.
4. Strengthen the Prefrontal Cortex — Enhance Emotional ‘Braking’ Ability
Mindfulness, deep breathing, emotional journaling, and CBT techniques enhance the prefrontal cortex’s ability to regulate the amygdala. For HSPs, this is a crucial pathway: with a strong brake system, sensitivity becomes strength rather than anxiety.
5. Nutritional Support — A Preview for the Next Article
The HSP nervous system consumes more energy and has higher nutrient demands: magnesium (calming the nerves), Omega-3s (stabilizing emotional circuits), vitamin B6 (supporting neurotransmitters), L-theanine (calm focus), and adaptogens like Ashwagandha or Rhodiola (balancing the stress system). These are well-supported scientific “buffers” for the nervous system. In the next article, we will break down how these nutrients help the brain regain stability.
Illustration of protection and noise reduction strategies for HSP nervous systems
Illustration: A highly sensitive brain functions like a high-precision microphone— it needs noise reduction, rhythmic restoration, and nutritional support to perform steadily.

 

Authors:

Louise W Lu

Louise W Lu

Registered Nutritionist (NZ Reg. 82021301), PhD of Nutrition Science, Honorary Academic at the University of Auckland. Louise blends clinical research with public health to help people eat better and live stronger.

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Alexandra V Goldberg

Alexandra V Goldberg

Registered Dietitian (NZ Reg. 20-02273) and expert in nutrition, medicinal chemistry, and skincare. Alexandra helps clients reach their health goals with science-backed strategies in post-op recovery, feeding tolerance, and weight management.

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