# Crossed Neurons? **URL:** \ **Category:** Factual Questions\ **Created:** [June 15, 2001, 12:05pm UTC](https://boards.straightdope.com/t/crossed-neurons/68919 "2001-06-15T12:05:59Z")\ **Posts on this page:** 10\ **Page:** 1
**Author:** ![Pleonast](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/pleonast/32/1183_2.png) [@Pleonast](https://boards.straightdope.com/u/Pleonast)\ **Post date:** [June 15, 2001, 12:05pm UTC](https://boards.straightdope.com/t/crossed-neurons/68919/1 "2001-06-15T12:05:59Z")
For some time, I’ve been noticing a strange sensing phenomenom. Here’s how it typically goes: I’m lying in bed, half-awake, listening to the radio. The air conditioning unit turns on and makes a pop! sound. At the same time as the pop!, I perceive a visual flash. Then I perceive the audial pop!. More details:[ul] [li] I’m always in relaxed state, either half-awake/half-asleep, or in meditative state.[/li][li] My eyes are always closed.[/li][li] The pop! has come from several sources: AC, refrigerators, car back-fires, slammed doors. Basically, any short, loud sound.[/li][li] The flash is always perceived (slightly) before the pop!.[/ul][/li] So, does anyone else experience this sort of thing? Any theories to what’s going on? Do I need to see a neurologist? I have two guesses to the cause:[ol] [li] I have a couple crossed neural paths. So a strong audial signal crosstalks into my visual wiring.[/li] My eyes do an autonomous flinch when there’s a loud sound. The produces visual stimulation also.[/ol] ---
**Author:** ![Mangetout](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/mangetout/32/19_2.png) [@Mangetout](https://boards.straightdope.com/u/Mangetout)\ **Post date:** [June 15, 2001, 12:56pm UTC](https://boards.straightdope.com/t/crossed-neurons/68919/2 "2001-06-15T12:56:00Z")
You may be experiencing what’s known as [synaesthesia](http://www.thecure.com/robertpages/synaesthesiapiece.html) ---
**Author:** ![Pleonast](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/pleonast/32/1183_2.png) [@Pleonast](https://boards.straightdope.com/u/Pleonast)\ **Post date:** [June 16, 2001, 2:28am UTC](https://boards.straightdope.com/t/crossed-neurons/68919/3 "2001-06-16T02:28:09Z")
Thanks, **Mangetout** , that was an excellent lead. My experience is not as intense as a true synaesthesian, but it’s the same basic phenomenom. ---
**Author:** ![Nukeman](https://avatars.discourse-cdn.com/v4/letter/n/ce7236/32.png) [@Nukeman](https://boards.straightdope.com/u/Nukeman)\ **Post date:** [June 16, 2001, 10:08am UTC](https://boards.straightdope.com/t/crossed-neurons/68919/4 "2001-06-16T10:08:58Z")
Yes! I get this, but usually only when there is a loud noise when I am in bed just before sleep - I get a white flash in my vision, which certanly wakes me up pretty quickly to see what made the noise- maybe its a self defence mechanism. ---
**Author:** ![Neurodoc](https://avatars.discourse-cdn.com/v4/letter/n/848f3c/32.png) [@Neurodoc](https://boards.straightdope.com/u/Neurodoc)\ **Post date:** [June 17, 2001, 10:23am UTC](https://boards.straightdope.com/t/crossed-neurons/68919/5 "2001-06-17T10:23:59Z")
Your symptoms are fairly common, and are probably what are called “Sleep Starts,” due to a poorly defined hyperexcitablity of the central nervous system as you fall asleep. A frequent co-symtom is a lightening-like jolt that results in adduction spasm of the legs. If you have this, you are almost certainly experiencing a hypnogogic sleep starle response. This hyperexcitability is more common when you are exhausted and “stressed out.” Synesthesia is a relatively rare phenomenon. It seems to be due to abnormal interconnections between normally separate sensory circuits—e.g. the person who “hears” or “tastes” colors, etc., etc. ---
**Author:** ![Pleonast](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/pleonast/32/1183_2.png) [@Pleonast](https://boards.straightdope.com/u/Pleonast)\ **Post date:** [June 19, 2001, 2:10pm UTC](https://boards.straightdope.com/t/crossed-neurons/68919/6 "2001-06-19T14:10:33Z")
Could it be more of a “Sleep Ends”? The symptons appear usually in the late afternoon/early evening after I’ve taken a 10-20 minute rest/nap/meditation. It’s in more of a becoming-more-active state, not a becoming-less-active one. I’ve never had any physical motion associated with it. It’s good to hear about the variety of different sensations that people experience. ---
**Author:** ![bughunter](https://avatars.discourse-cdn.com/v4/letter/b/aeb1de/32.png) [@bughunter](https://boards.straightdope.com/u/bughunter)\ **Post date:** [June 19, 2001, 7:06pm UTC](https://boards.straightdope.com/t/crossed-neurons/68919/7 "2001-06-19T19:06:51Z")
No, it’s not synaesthesia, nor sleep starts. It’s just an autonomic reaction to being mildly startled, the same as the “fight or flight” reaction, just to a lesser degree. This is causing your irises to momentarily dilate and allow more light in. You perceive this as a “flash.” So yes, in a way you could say you have your “neurons crossed.” But they’re supposed to be crossed that way. As for the relative timing of your wisual and aural perceptions, I cannot guess - but a large portion of the brain is devoted to visual processing, more than for sound (and there’s a lot of that, too). Perhaps that has something to do with it. ---
**Author:** ![ignatzmouse](https://avatars.discourse-cdn.com/v4/letter/i/b2d939/32.png) [@ignatzmouse](https://boards.straightdope.com/u/ignatzmouse)\ **Post date:** [June 20, 2001, 2:16am UTC](https://boards.straightdope.com/t/crossed-neurons/68919/8 "2001-06-20T02:16:26Z")
> [@](#): > > the relative timing of your wisual and aural perceptions When I read this phrase, I have an involuntary image of Walter Koenig. Does this mean that my neurons are crossed? I’m wondering why bughunter ruled out sleep starts. ---
**Author:** ![Pleonast](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/pleonast/32/1183_2.png) [@Pleonast](https://boards.straightdope.com/u/Pleonast)\ **Post date:** [June 20, 2001, 12:26pm UTC](https://boards.straightdope.com/t/crossed-neurons/68919/9 "2001-06-20T12:26:30Z")
I like **bughunter** ’s explanation the best so far. I can test the iris hypothesis by checking if there’s no longer a flash when I’m in a completely darkened room. He probably ruled out sleep starts because of my previous comments. I think there’s some element of hyper-excitability, in that I only notice the effect when I’m in a relaxed state (so there’s a lack of other stimuli). But the the stress-out and physical-motion elements of the sleep start don’t really fit my case. > [@](#): > > I have an involuntary image of Walter Koenig. This sounds like a serious pathology. See a doctor at once. 😉 ---
**Author:** ![bughunter](https://avatars.discourse-cdn.com/v4/letter/b/aeb1de/32.png) [@bughunter](https://boards.straightdope.com/u/bughunter)\ **Post date:** [June 20, 2001, 9:47pm UTC](https://boards.straightdope.com/t/crossed-neurons/68919/10 "2001-06-20T21:47:05Z")
> [@](#): > > **But the the stress-out and physical-motion elements of the sleep start don’t really fit my case.** Exactly. And also, sleep starts do not occur in response to external stimulus. I get them myself sometimes. (I once sleep started so violently I kicked the wall next to my bed and broke my toe. I didn’t fall asleep anytime soon after that!) > [@](#): > > **wisual** Heh. I don’t know how I did that. The _w_ is nowhere near the _v_ – talk about crossed neurons! I need to have my motor cortex examined.