The Curious Case of Dr. Nuro and the Shrinking Startle

Dr. Nuro was not your average neuroscientist. She had an unusual hobby: she ran a skydiving neuroscience lab. Yes, you read that right. Strapped to the backs of plummeting grad students were EEG caps, pulse monitors, and more cameras than a reality TV reunion. Her mission? To understand how the brain learns to chill out—or freak out—when the world won’t stop screaming at it.

Her favorite case? A graduate student named Toby.

Toby was the ultimate jumpy test subject. His startle reflex was legendary—he once yelped at a wind chime. Dr. Nuro, thrilled, made him the prime subject of her Habituation & Sensitization project.

Day 1: Jump 1.
Toby was launched from the plane. Heart racing, face twisted in horror. Cameras caught a perfect State A expression: pure, unfiltered terror. But once his feet hit the ground, something interesting happened—he laughed. That was State B—the after-feeling. The exhilaration. Dr. Nuro took notes. Dual-process theory in action. The primary reaction (terror) might weaken with repetition, but the after-feeling? That could increase.

Jump 4:
Toby’s screams were shorter. He stopped grabbing the instructor’s leg midair. His startle response had begun to habituate. Why? Because of a quiet neural process unfolding deep in his spinal cord: his S-R (stimulus-response) system was adapting.

You see, habituation isn't fatigue—Toby’s legs still kicked; they just didn’t care anymore. The same stimulus (falling through the sky) was repeated, and the sensory neurons—originally yelling “PANIC!”—now whispered, “Eh, been there.” Synaptic transmission weakened. Less neurotransmitter. Reduced post-synaptic response. The reflex itself got quieter.

But then came Jump 5—where a rogue goose flew near the plane. New, intense stimulus. BAM. The State System (arousal-based) kicked in. Toby screamed like he was on fire. This was sensitization—an increase in response, driven by a separate neural track, lighting up like Times Square during New Year’s Eve.

Dr. Nuro was ecstatic. She showed her lab rats (the students, not the literal ones) a diagram:

• The S-R system handled habituation: low-level, reflex-based adaptation.

• The State System handled sensitization: activated by intense or novel stimuli. Like sky geese.

But Dr. Nuro wasn’t done. She ran a post-jump study on after-feelings. Toby reported: “At first, I was terrified. But now I love the thrill.” Dr. Nuro hypothesized that while the fear (State A) habituated, the joy (State B) sensitized—it grew stronger as the fear faded.

She called it the “motivational momentum” model: we're not driven by the stimulus—but by the emotional echo. That lingering feeling after it's over.

Over time, she even observed stimulus-specific habituation: if Toby jumped with a red parachute every time, and suddenly got a blue one—dishabituation! His nervous system said: “Wait, this might be new danger.” But repeat the blue? Habituation returned—faster this time. That’s time-tracking in the brain—neurons remembering how long it's been since they last shrugged something off.

So, what did Dr. Nuro conclude?

1. All nervous systems habituate—it’s survival. You don’t want to keep freaking out at ceiling fans.

2. Reflexes exist to protect, but their urgency fades with familiarity.

3. Habituation and sensitization are two separate, coexisting systems—a neural yin and yang.

4. And the real kicker? People jump out of planes not for the fall—but for the afterglow.

And Toby? He became an instructor. Still jumps. Still laughs. Still has no idea the goose incident made him famous in four journals and one TEDx talk.