# Brain flash with a 9Volt Battery
**URL:** https://boards.straightdope.com/t/brain-flash-with-a-9volt-battery/22531
**Category:** Factual Questions
**Created:** [June 16, 2000, 12:16am UTC](https://boards.straightdope.com/t/brain-flash-with-a-9volt-battery/22531 "2000-06-16T00:16:09Z")
**Posts on this page:** 17
**Page:** 1
### Author:  [@insider](https://boards.straightdope.com/u/insider)
#### Post date: [June 16, 2000, 12:16am UTC](https://boards.straightdope.com/t/brain-flash-with-a-9volt-battery/22531/1 "2000-06-16T00:16:09Z")
I read somewhere that if you hook up a wire to each terminal of a 9Volt and put one lead on your forhead and one on your tongue you will experience a flash. Is this true or does anyone have any info? Thanks
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### Author:  [@UncleBeer](https://boards.straightdope.com/u/UncleBeer)
#### Post date: [June 16, 2000, 12:31am UTC](https://boards.straightdope.com/t/brain-flash-with-a-9volt-battery/22531/2 "2000-06-16T00:31:39Z")
Where’s your sense of adventure? Where’s your dedication to science, man? Give it a try.
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### Author:  [@Ike\_Witt](https://boards.straightdope.com/u/Ike_Witt)
#### Post date: [June 16, 2000, 12:44am UTC](https://boards.straightdope.com/t/brain-flash-with-a-9volt-battery/22531/3 "2000-06-16T00:44:50Z")
I’m glad a mod suggested that he try it. That way the thread and all incriminating evidence can be deleted, should something go wrong 😉
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### Author:  [@manhattan](https://boards.straightdope.com/u/manhattan)
#### Post date: [June 16, 2000, 12:47am UTC](https://boards.straightdope.com/t/brain-flash-with-a-9volt-battery/22531/4 "2000-06-16T00:47:58Z")
Thread? What thread? I don’t see any thread.
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### Author:  [@red\_dragon60](https://boards.straightdope.com/u/red_dragon60)
#### Post date: [June 16, 2000, 1:03am UTC](https://boards.straightdope.com/t/brain-flash-with-a-9volt-battery/22531/5 "2000-06-16T01:03:59Z")
I don’t think it would work. My basis is this- to test if a 9V battery has juice, on occasions I have touched my tongue to both contacts. This produces a wonderful tingling, but not much else. Try it! Hmm, licking batteries for a buzz sounds just as funny as licking toads. Mmmm, toad…
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### Author:  [@TheNerd](https://boards.straightdope.com/u/TheNerd)
#### Post date: [June 16, 2000, 2:03am UTC](https://boards.straightdope.com/t/brain-flash-with-a-9volt-battery/22531/6 "2000-06-16T02:03:35Z")
You will see a flash if you put both terminals to the inside of your upper lip. At least, I do.
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### Author:  [@Luckie](https://boards.straightdope.com/u/Luckie)
#### Post date: [June 16, 2000, 2:59am UTC](https://boards.straightdope.com/t/brain-flash-with-a-9volt-battery/22531/7 "2000-06-16T02:59:48Z")
In junior high i touched a 9volt to my braces.
i got zoinked.
muscles jerked, loud sound in my head (no sound outside my head), and eyes went black for an instant and faded back in over the course of a couple seconds.
very interesting, kinda cool in a demented way.
but i never repeated, and don’t particularly have the urge to.
-luckie
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### Author:  [@argyle87](https://boards.straightdope.com/u/argyle87)
#### Post date: [June 16, 2000, 7:35am UTC](https://boards.straightdope.com/t/brain-flash-with-a-9volt-battery/22531/8 "2000-06-16T07:35:47Z")
My friend tried to kill himself by licking a nine-volt battery.
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Okay, well, I made that up. But wouldn’t that be the funniest obituary ever?
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### Author:  [@wastelands](https://boards.straightdope.com/u/wastelands)
#### Post date: [June 18, 2000, 1:39am UTC](https://boards.straightdope.com/t/brain-flash-with-a-9volt-battery/22531/9 "2000-06-18T01:39:08Z")
touching to your tongue is cool, plus as I was reading it I noticed a bonus. just thinking about doing it brings back the feel and taste. Anyone else ever has this happen?
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### Author:  [@Derleth](https://boards.straightdope.com/u/Derleth)
#### Post date: [June 18, 2000, 2:00am UTC](https://boards.straightdope.com/t/brain-flash-with-a-9volt-battery/22531/10 "2000-06-18T02:00:42Z")
In response to the OP, I’d try it. I doubt a 9V would have the juice to really fry you, and you’d doubtless get the same reaction as **Luckie**. He turned out fine, didn’t ya, Luck?
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### Author:  [@2nd\_Law](https://boards.straightdope.com/u/2nd_Law)
#### Post date: [June 18, 2000, 2:12am UTC](https://boards.straightdope.com/t/brain-flash-with-a-9volt-battery/22531/11 "2000-06-18T02:12:14Z")
Once when I was but a lad, when I was trying to figure out how to build a railgun with a capacitor I took out of a broken flash unit, I inadvertantly put both the wires connected to the capacitor in my mouth at the same time.
Yep, definately saw a flash. IIRC, damn near dislocated my jaw, too.
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### Author:  [@aha](https://boards.straightdope.com/u/aha)
#### Post date: [June 18, 2000, 2:32am UTC](https://boards.straightdope.com/t/brain-flash-with-a-9volt-battery/22531/12 "2000-06-18T02:32:15Z")
when I was little a friend of mine had an old crank telephone. We use to join hands in a circle as one of us slowly cranked the old telephone which was hooked up to a car battery. The faster the crank the hight the voltage. The first one to let go was the loser/winner.
Oh yeah those were the times…
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### Author:  [@AWB](https://boards.straightdope.com/u/AWB)
#### Post date: [June 18, 2000, 2:57am UTC](https://boards.straightdope.com/t/brain-flash-with-a-9volt-battery/22531/13 "2000-06-18T02:57:54Z")
A friend of mine in junior high hooked up a D-cell to a massive transformer which lowered the current but upped the voltage to 25000. He’d have his victim touch two terminals with his thumbs, then he’d hit a hidden On switch. Their arms would _fly_ off the terminals by reflex. Pretty cool.
Then we got sadistic and tried to see how long anyone could hold their thumbs on. A couple of guys got to 2 seconds. But then one guy really amazed us by doing it for 10 seconds. It was rather akin to riding a rodoe bull. 😃
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### Author:  [@Derleth](https://boards.straightdope.com/u/Derleth)
#### Post date: [June 18, 2000, 4:19am UTC](https://boards.straightdope.com/t/brain-flash-with-a-9volt-battery/22531/14 "2000-06-18T04:19:09Z")
Bit of warning: I can easily see someone frying their nerves quite literally by trying to pump all that juice through them at once. Like circuitboards can be ruined by too much energy, nervous systems can be damaged by the same. And nerves heal slowly, if at all. If you don’t mind being a bit numb and weak, by all means have at it. Just don’t say we didn’t warn you.
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### Author:  [@dropzone](https://boards.straightdope.com/u/dropzone)
#### Post date: [June 18, 2000, 5:41am UTC](https://boards.straightdope.com/t/brain-flash-with-a-9volt-battery/22531/15 "2000-06-18T05:41:52Z")
> [@](#):
>
> touching to your tongue is cool, plus as I was reading it I noticed a bonus. just thinking about doing it brings back the feel and taste. Anyone else ever has this happen?
Is this some sort of post-modern, Proustian thing?
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### Author:  [@Gunslinger](https://boards.straightdope.com/u/Gunslinger)
#### Post date: [June 18, 2000, 11:07pm UTC](https://boards.straightdope.com/t/brain-flash-with-a-9volt-battery/22531/16 "2000-06-18T23:07:56Z")
> [@](#):
>
> \*\*
> A friend of mine in junior high hooked up a D-cell to a massive transformer which lowered the current but upped the voltage to 25000. He’d have his victim touch two terminals with his thumbs, then he’d hit a hidden On switch. Their arms would _fly_ off the terminals by reflex. Pretty cool.
>
> Then we got sadistic and tried to see how long anyone could hold their thumbs on. A couple of guys got to 2 seconds. But then one guy really amazed us by doing it for 10 seconds. It was rather akin to riding a rodoe bull. 😃
> \*\*
What fun! In my physics class the teacher brought in a 30,000 volt Van der Graf static-electricity generator (the metal ball on a post thingy). She had the whole clas hold hands in a line across the room (I ended up in the middle). Then she told the person on one end to put a hand on the generator, and the other end to grab one of the lab faucets at the back. I was the only one in the class that knew what was gonna happen. “No, you idiot, you’ll ground…_ZAP!_…us.”
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### Author:  [@madd1](https://boards.straightdope.com/u/madd1)
#### Post date: [June 19, 2000, 12:56am UTC](https://boards.straightdope.com/t/brain-flash-with-a-9volt-battery/22531/17 "2000-06-19T00:56:19Z")
To the OP…
Moisten your forhead first.
Also try your temple.
Please post results, in the name of science.