Viva Las Vagus (and Trigeminal)

Alejandro Covalin [00:00:01]:
Have you ever wanted to know the full story of a medical device company? From the initial spark of an idea to launching an FDA-approved product. I'm Dr. Alejandro Covalin, Chief Technology Officer at Spark Biomedical. With me are my co-founders, Daniel Powell, CEO, and Dr. Navid Khodaparast, Chief Science Officer. Welcome to Spark: A Conversation.

Daniel Powell [00:00:24]:
I remember the first time the two of you put this concept together for me—that we’re going to hit the vagus nerve and the trigeminal. I was pretty familiar with the vagus nerve from implantable devices for epilepsy. But I guess we come back to: what do they each do independently, and why put them together?

Navid Khodaparast [00:00:54]:
The vagus is just... no offense to the trigeminal.

Daniel Powell [00:01:00]:
The trigeminal expert. The vagus expert’s all right. Can we get the Fight Club vagus shirt?

Navid Khodaparast [00:01:11]:
Hashtag vagus.

Daniel Powell [00:01:12]:
Put that in the marketing.

Alejandro Covalin [00:01:13]:
Vagus is larger, that’s for sure.

Daniel Powell [00:01:15]:
Vagus is what?

Alejandro Covalin [00:01:16]:
Is a larger nerve.

Navid Khodaparast [00:01:17]:
It’s a much larger nerve. Yeah, but the vagus is important for a lot of reasons. One, it’s one of 12 cranial nerves. The trigeminal is one. But what’s cool—in Latin, it’s the “wandering” nerve. It’s the only cranial nerve that leaves your head and goes throughout your body.

Navid Khodaparast [00:01:44]:
It connects to your heart, lungs, almost every organ system. So if I can deliver electricity to this nerve—it can change your heart rate—what does it do to your spleen? Your stomach? Maybe I can help with that too.

Alejandro Covalin [00:02:12]:
It’s very interesting. This nerve sends and receives signals. So depending on how you stimulate it, you may affect different systems—your heart, your spleen. It’s not one-size-fits-all.

Daniel Powell [00:02:48]:
Traditionally, we thought: if you’re going to hit the vagus nerve, go for the neck, where it's in the carotid sheath. But then you guys said, “Let’s hit it from the ear.” So we’re hitting branches of the vagus and trigeminal nerves.

Navid Khodaparast [00:03:16]:
We get that a lot—“Are you stimulating the vagus nerve?” Yes, a branch of it, on your ear.

Daniel Powell [00:03:34]:
That ridge we call the simba concha, right above the ear canal.

Navid Khodaparast [00:03:38]:
Yes, the simba concha.

Daniel Powell [00:03:40]:
Where we access it.

Alejandro Covalin [00:03:41]:
It comes from the back and goes into the ear.

Navid Khodaparast [00:03:47]:
It comes off the vagus nerve—hence, auricular branches.

Daniel Powell [00:03:52]:
Do we need to get the anatomy software out?

Navid Khodaparast [00:03:55]:
Yes. And then, the trigeminal nerve goes all over your face. It really branches out.

Alejandro Covalin [00:04:10]:
It has three branches.

Navid Khodaparast [00:04:11]:
Tri-geminal.

Daniel Powell [00:04:15]:
I was nodding like I knew that already—I didn’t.

Alejandro Covalin [00:04:20]:
It’s collecting all this sensory information.

Navid Khodaparast [00:04:24]:
And we can access both vagus and trigeminal branches around the ear—which is convenient. Imagine having to stimulate the ear and the forehead. That would be intrusive.

Daniel Powell [00:04:47]:
The convenience of it being compact.

Alejandro Covalin [00:04:50]:
Exactly. The trigeminal branch is right here, and the vagus branch is right here. Co-located.

Navid Khodaparast [00:05:06]:
Alejandro’s going to want occipital next.

Alejandro Covalin [00:05:08]:
Yeah, some occipital branches go to the spine right here too. Very convenient location.

Daniel Powell [00:05:19]:
So why stimulate these two nerves together?

Navid Khodaparast [00:05:22]:
That’s the theory of synergism. Both nerves go to the brain and synapse in the same spot. If we stimulate both, it’s like pushing something with two people instead of one—more force, more neurotransmitters, more dopamine. Better withdrawal response.

Alejandro Covalin [00:06:11]:
And if two nerves are sending the same signal, the brain pays more attention. Like when two people tell you the same thing—it holds more weight.

Navid Khodaparast [00:06:54]:
That’s synergism. More, in this case, is better.

Daniel Powell [00:07:00]:
And the result is autonomic balance. The amygdala—where you process fear and pain—is in a hyper fight-or-flight state.

Alejandro Covalin [00:07:13]:
Very sympathetic.

Daniel Powell [00:07:14]:
So we want to shift from sympathetic (fight/flight) to parasympathetic (rest/digest).

Alejandro Covalin [00:07:22]:
Exactly. People in withdrawal are stuck in that hyper-sympathetic mode.

Navid Khodaparast [00:07:34]:
And you can see that in brain scans—parts of the brain firing like crazy. So we try to quiet those signals. Vagus stimulation slows the heart and restores parasympathetic tone.

Navid Khodaparast [00:08:13]:
That improves autonomics—gets people back to baseline.

Daniel Powell [00:08:25]:
People wonder how this helps so many conditions—epilepsy, PTSD...

Alejandro Covalin [00:08:33]:
There’s no magic.

Daniel Powell [00:08:35]:
Right. It's autonomic imbalance. That wandering nerve hits every major organ. Restoring balance could help multiple systems.

Alejandro Covalin [00:09:06]:
And triggering parasympathetic activity changes neurochemical output. That can improve mood, learning, healing—even cognition.

Alejandro Covalin [00:10:19]:
It’s not just parasympathetic balancing. We’re also activating cognitive centers in the brain that support learning, neuroplasticity, even forgetting—because that’s part of learning too.

Daniel Powell [00:10:50]:
We’ve been doing heart pacemakers for 80–90 years. Where are we in the lifecycle of this?

Navid Khodaparast [00:11:06]:
I think we’re in the middle. Auricular neurostimulation isn’t new—it’s just becoming more mainstream.

Navid Khodaparast [00:11:23]:
We need more studies, more refinement. There’s method behind the magic.

Alejandro Covalin [00:11:43]:
It’s old science.

Daniel Powell [00:11:45]:
We didn’t know how old until you found that paper from Russia—1947. Auricular stimulation.

Navid Khodaparast [00:12:04]:
Yeah.

Alejandro Covalin [00:12:04]:
The idea’s old. What’s changed is the tech and our understanding.

Daniel Powell [00:12:21]:
And now we can use fMRI to see what’s happening in the brain in real time.

Alejandro Covalin [00:12:26]:
And adjust the tech accordingly.

Daniel Powell [00:12:39]:
I agree—we’re in the middle. The biggest breakthroughs are still ahead.

Alejandro Covalin [00:12:49]:
That’s always the case. You need the slow first half to know what to do. Then the second half feels like rapid progress.

Navid Khodaparast [00:13:10]:
That’s discovery.

Daniel Powell [00:13:20]:
Awesome.

Alejandro Covalin [00:13:21]:
That second half is the application.

Daniel Powell [00:13:27]:
And I feel like that’s us.

Navid Khodaparast [00:13:30]:
We’re on that ramp.

Daniel Powell [00:13:31]:
Just at the beginning—but we feel it.

Navid Khodaparast [00:13:35]:
Yeah.

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