What causes hallucinations and sounds while meditating?

Seth;

If you spend any amount of time on any meditation forum, you will see posts such as the following:

On very rare occasions I start hallucinating during meditation.
Does everybody experience hallucinations, replayed memories and imagery during meditation?
Does anyone here experience visual hallucinations while meditating?
I experienced a few moments where my whole body started to vibrate. Thoughts?

(All of these were topics from /r/meditation)

So seeing or hearing things while sitting in meditation seems pretty common. But why?

In my years of meditation and running this site I have seen many explanations. Here's a few possible explanations:

The meditator's third eye is opening to a higher plane.
The meditator's /posts/interesting-stuff/my-experience-with-kundalini-yoga/ is rising, causing visions and sounds.
The mind uses these images or sounds to distract the meditator from their meditation.
The meditator's body released DMT.
The meditator is about to leave his or her body via astral projection.
Demons are infiltrating the meditator's mind.
The meditator is one step closer to achieving enlightenment/nirvana/samadhi.

Now most of those explanations seem a tad... outlandish... especially to those meditators who do not believe in such things. In my opinion, I believe the explanations is much simpler than that.

The meditator is falling asleep.

Wow, that's kind of boring compared to the other possible explanations. But, hear me out, it will make sense.

The Hypnagogia State

The hypnagogia state is the transitional state between being awake and being asleep. According to the Wikipedia article on Hypnagogia, this state can include a "wide variety of sensory experiences. These can occur in any modality, individually or combined, and range from the vague and barely perceptible to vivid hallucinations." Below are a few different kinds of hallucinations people can experience in this state.

Sights

Sight is one of the more commonly reported hallucinations. They can range from being a bunch of lines and shapes to faces to full blown landscapes. Movement through a tunnel is also sometimes reported as well. My boyfriend has told me that he has seen tigers in a forest during some of his meditation sessions. For me personally, I don't have sight hallucinations during meditation or falling asleep. Clearly I need to open my third eye more ;)

Tetris Effect

The tetris effect is one I have experienced. You know the feeling when you spend the day in a wave pool or in the ocean go home and go to sleep it feels like you're still in the waves? That's the tetris effect. Any repetitive task done while awake can trigger it such as jumping on a trampoline, or even working at a checkout counter for 8 hours moving stuff over the scanner. This is one I have personally experienced while falling asleep, though I'm not sure if I've experienced it during meditation.

Sounds

Hearing sounds is another hallucination that can occur during this state. These can range from static, to voices, to loud bangs and pops. While falling sleeping, I have heard my name called out to me and various other voices (younger me was kind of freaked out by this).

And More!

However, there are some more creepy experiences that can happen as well. Sleep paralysis, which is a state where your body is asleep and paralyzed but your mind is awake, can occur. During this state, you are awake, but can't move your body. You might be able to feel "tingles" or "vibrations" during this state. Some people report seeing and old hag or witch or demon sitting on their chest or feel a very dark presence while paralyzed. Luckily, I've yet to experience sleep paralysis. My boyfriend has, but he's never seen anything scary while paralyzed; he usually just falls back asleep. However, taking a stroll to /r/sleepparalysis and you'll see some of the scary experiences people may have during this state. If you do end of in sleep paralysis, just remember, anything you see is not real (though from what I've read, thinking that is easier said than done).

Conclusion

So there you have it! A logical explanation as to why you may be seeing or hearing things during meditation. You are simply in the hypnagogia state while meditating. No demons or third eyes awakening or anything like that. That's not to say that those other explanation's aren't possible. They might be! I personally don't believe in it, but that doesn't mean that you shouldn't if you do believe.

But what should you as the meditator do during this state?

Interestingly, for both the "outlandish" explanations and this one, the general consensus from what I've seen is the same. They are a distraction. Acknowledge it, and return to your meditation technique. So regardless of what you believe in, its recommended to simply ignore it and refocus on whatever you were meditating on. And that's why meditation is awesome! Different backgrounds, different techniques, different beliefs, all leading to the same thing.

Happy Meditating!

-Seth

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