Nitrous Oxide effect on auditory perception

[MyExcuse]

Recently I've been toying around with nitrous oxide and have noticed something interesting. I can't seem to find much on the impact of nitrous oxide on the perception of sound in literature, and I was hoping someone may be able to shed some light.

Anyone familiar with N2O has experienced the "wah-wah" throbbing drone, which slowly tapers off as the effects subside. I've discovered, for myself at least, this effect is modulated by the frequency of sound heard. Particularly, higher pitched noises become much more perceptible beyond the "wah-wah" throbbing tonality.

An example is that of wind rustling through the leaves of a tree becoming much more perceptible. I live in a 2-story condo, and the sound of wind through the trees parallels the sound of a car passing by. What is interesting most of all, is that the threshold for perceptibility is dramatically increased. What I mean is, the "wah-wah" sound will match the onset of the sound of the wind at a higher frequency of which I normally am not as consciously aware of.

To put it simply, it is as if my ability to hear higher frequency tones is enhanced.

Conversely, lower frequency tones are unaffected (eg, a bathtub filling in an adjacent room).

Is there any known explanation for the auditory impact of nitrous oxide inebriation?

P.S. For what it is worth, I keep a canister of aviators breathing oxygen (95%) on hand and balance my inhalation of nitrous with relatively pure oxygen.

 

[JessFR]

I dunno the explanation, but yeah I remember that being an effect back when I used nitrous many years ago.

 

[dopamimetic]

Get this sometimes on other dissociatives too, was very pronounced on extended DCK sessions.. There's an explaination in White's DXM FAQ, he calls it 'flanging', caused by a slowdown of sensory input and processing, somehow like you getting lagged frames but auditorially. It's pretty nice and somehow dissociation is indeed able not only to lower but also to heighten sensoric resolution. But leave it to others with better English to explain the concept..

 

[jackie jones]

Well, it is certainly distorted, I would say impaired as well.

I think "Wah-wah" is a good description of the sound. I would not say that auditory distortion would be one of the Pros of doing Nitrous. I do not do it anymore (I think I have done enough), but I would say the pros would be an overall psychedelic, slightly dissociative, sedating effect.

 

[dopamimetic]

It can become pretty interesting with eg DCK when you have plenty of time to get used to and to analyze it, then it's not really an impairment but more of access to the unfiltered input (somehow I guess the wah-wah are echos from the soundwaves getting reflected at surfaces of houses, walls, etc.. as it's particularly pronounced with traffic and similar noise. Not really sure though and might even be a related but different phenomenon.) But can be annoying too and not really a pro, yeah.

 

[polymath]

Other anesthetic gases and vapors cause this auditory effect too, it can also sound like crickets or a bicycle's bottle dynamo. And then there's that 'deja vu' effect, "the high has begun like this every time".

 

[dopamimetic]

Other anesthetic gases and vapors cause this auditory effect too, it can also sound like crickets or a bicycle's bottle dynamo. And then there's that 'deja vu' effect, "the high has begun like this every time".

Afaik the deja vu phenomen has been linked to instabiities (seizure-less seizures) and dissociatives appear to facilitate such kind of activity in this lobe (the DXM FAQ by White covers this topic somewhat, and also the 'flanging' which is the theory concept about frame rates of sensory input, that dissociatives will lover that as dosage increases, which results in flanging).

9.2.5 Temporal Lobe Involvement
Probably the greatest degree of DXM's effects come from consequences of the aforementioned receptor binding on the temporal lobe limbic areas. The blockade of NMDA receptors by DXM has specific consequences in these areas. The normal functioning of the hippocampus and amygdala are disrupted since NMDA blockade prevents long-term potentiation. The posterior cingulate and retrosplenial cortex paradoxically become more active. There may be spontaneous "noise" effects in the entire limbic system amplified by feedback. One paper suggested that dissociatives may induce "microseizures" or limited areas of high activity in the limbic system (176).

There is also the suggestion of a "top-down" inhibition of the senses, i.e., inhibitory signals from the limbic areas and surrounding cortical areas are sent "down" to sensory networks, lowering the strength of sensory data. This "top-down" inhibition of the senses may be the mechanism behind dissociative anaesthesia; sensory information is still processed by the brain, but never makes it to the conscious mind and is never encoded in intermediate-term declarative memory (in the hippocampus).

Finally, dissociatives seem to alter the flow of signals through the limbic areas, possibly increasing the degree of internal feedback within these areas (or between these areas and the neocortex) and diminshing the amount of sensory data that comes in. Gating of signals coupled to the theta rhythm through the posterior cingulate (311) may be altered.

Putting this all together into some sort of cohesive theory may be too soon but I'm going to do it anyway. My belief (which will probably change as new research becomes available) is that the diminished sensory data (from top-down inhibition), and the decreased encoding of intermediate-term memory, combined with the enhancement of activity in the posterior cingulate and retrosplenial cortex, all lead to an increasingly closed feedback loop. Within this loop, random noise, individual differences in temporal lobe "wiring", the contents of intermediate memory, and the influence of electromagnetic fields (332) all combine to give rise to profoundly abnormal neural patterns.

An interesting aside to this is that the sense of smell is sometimes reported to be enhanced on DXM. This hasn't been formally studied, and may be all in one's mind, but since olfactory data is treated somewhat differently by the brain than the other senses, it may be spared from the descending inhibitory signals that attenuate other sensory data. If so, then the feedback loop could actually serve to increase the strength of olfactory data, by repeatedly adding the same, small signals together.



9.2.7 Flanging


One of DXM's most prominent effects if the flanging of sensory input. This happens to some extent with many drugs, and I have a hypothesis on this. Note in particular the relation of flanging to "stoning" and "buzzing" - in some ways, flanging is a more profound degree of stoning. Some people have noticed a flanging or strobing effect after smoking a great deal of cannabis, and nitrous oxide users are also familiar with flanging of sounds. Even alcohol can produce it.

What it seems many of these drugs have in common is the ability to inhibit hippocampal long-term potentiation. Some have suggested that there are more than one set of signals that pass through the same limbic areas, with those in phase with the theta frequency and those out of phase being gated differently. Perhaps one set of signals is more strongly involved with memory, and the other set more strongly involved with sensory data. Or, perhaps all drugs which inhibit hippocampal LTP all activate the posterior cingulate cortex. In either case, signals at one phase of the theta rhythm could be disrupted, leading to a pulsing of perception in step with theta rhythm.

A different theory is that networks in the brain will re-process the same data repeatedly until a stable configuration is formed, and that DXM (and other drugs) slow down this process. With some networks slowed down and others operating at normal speeds, the characteristic frequencies of the two sets of signals would differ, leading to a "beat frequency" in much the same way that two very similar sounds can lead to a beat frequency (for a quick demonstration of this, listen to someone tuning a guitar by ear).

Then, we have papers like this: The Effects of Nitrous Oxide on Hearing

Yet which other anesthetic gases and vapors do you refer to, if these aren't dissociatives - like propofol for example? Somehow I was under the impression, that this specific sort of auditory effect was quite particular but I could have been wrong of course.

 

[polymath]

Yet which other anesthetic gases and vapors do you refer to, if these aren't dissociatives - like propofol for example?

I mean chloroform and other more dangerous chemicals you can get the same kind of effects from.

 

[MyExcuse]

Thank's to all for the input!

It's been about 10 years since I investigated psychedelic substances in any seriousness (for self-exploration purposes), and I'm certainly more attuned to the nuanced and granular aspects than I was when I was more youthful.

 

[polymath]

@dopamimetic Do you have experience combining nitrous oxide with other dissociatives? Would inhaling N₂O after a small dose (100-150 mg) of DXM produce a ketamine-like effect without the anxiety that large doses of DXM can cause?