Chameleon having nightmares?

[OreoPapii]

Do chameleons dream or have nightmares because very rarely my cham with wake up in the middle of the night I’ll hear him run around his cage like he’s scared and he will fall and things like that so I’m wondering if this is something bad or what’s going on and I wanna know if anyone has answers?

 

[Klyde O'Scope]

Yes, it's been known for a few years now that lizards dream. Here are some articles:
do reptiles dream?

“If you forced me to speculate and to use a loose definition of dreaming, I’d speculate that those dreams are about recent notable events: insects, maybe a place where there are good insects, an aggressive male in the next terrarium, et cetera,” said neuroscientist Gilles Laurent, director of the Max Planck Institute for Brain Research in Germany.
https://www.japantimes.co.jp/news/2...nightmare-rem-episodes-suggest-lizards-dream/

Whether some of those dreams can—or should—be characterized as "nightmares" is anybody's guess.

 

[Fchamel]

Wow! It's 10 am and I've learned two things! ?

 

[nightanole]

Meh happens to my beardies quite often. For some reason they wake up before light, and just walk around in the dark getting stuck and doing burn outs. They end up spending the rest of the night in the people bath tub till i wake up and put them back in the cage. Im not sleeping through all that racket.

 

[Klyde O'Scope]

Meh happens to my beardies quite often. For some reason they wake up before light, and just walk around in the dark getting stuck and doing burn outs. They end up spending the rest of the night in the people bath tub till i wake up and put them back in the cage. Im not sleeping through all that racket.

What's your secret? Mine's been dead to the world (brumating) since 9/18. He wakes up every week & a half or so, basks for a couple hours, then crawls back underneath... ? ?
I'm starting to wonder if he's part groundhog... coming out to look for his shadow...

 

[kinyonga]

In this thread,
https://www.chameleonforums.com/threads/do-chameleons-dream.122386/
Chris Anderson said...
"There has been one study on sleep in chameleons and it found that brief periods of rapid eye movement (REM) sleep is present in chameleons while sleeping, at least in the form of unilateral eye movements. Electroencephalograms, however, suggest no true REM sleep occurs (no change in the EEG trace between periods of REM and no eye movement). That said, their recordings were made in the telencephalon and recordings from the brain stem would really need to be made to confirm a lack of REM sleep. Now, REM sleep does not necessarily mean dreaming in mammals, and we really don't know if reptiles brains would be similar anyway in that regard."

I remember reading this study too.

 

[Klyde O'Scope]

In this thread,
https://www.chameleonforums.com/threads/do-chameleons-dream.122386/
Chris Anderson said...

FWIW, that thread is from 2013.
The study cited is from 2016. Granted, it was on bearded dragons.
The abstract can be found here.
"electrophysiological characteristics"; is that EEG?

Then there's this...



(Where's that smilie with its tongue jammed into its cheek?)

What's that action about 30 seconds in, where the one chameleon appears to kiss the other, then closes its eyes and has a snuggle? It appears it may conflict with the information here:
https://chameleonacademy.com/chameleon-behavior-eyes-shut/
Another reason for a chameleon closing its eyes during the day? I'm asking.

I just think there's a lot the experts don't know yet, but that's the way of science & knowledge! ?

 

[nightanole]

What's your secret? Mine's been dead to the world (brumating) since 9/18. He wakes up every week & a half or so, basks for a couple hours, then crawls back underneath... ? ?
I'm starting to wonder if he's part groundhog... coming out to look for his shadow...

I havent seen my tegu since october. I shine a light in the hole and an eyeball opens up, so hes still alive...

My beardies only brumate for 2-3 months, normally mid november till mid jan.

 

[Klyde O'Scope]

I havent seen my tegu since october. I shine a light in the hole and an eyeball opens up, so hes still alive...

That's what I do!!!

My beardies only brumate for 2-3 months, normally mid november till mid jan.

Well... that would have been nice, but it's his first time, and he made the decision—not me.
Meanwhile, the roaches just keep eating and growing... ?

I wonder if roaches have nightmares of being eaten alive by Gojira...

Wondering what the heck my dog dreams about too—he makes more noise in one night than he does in a month of being awake.... ?‍

 

[kinyonga]

" 44 reported evidence for REM sleep in the chameleon lizard. They reasoned that this animal, having very mobile active eyes in waking would be more likely to show eye movement periods during sleep. They, like most subsequent researchers working with reptiles, found relatively little modulation of forebrain EEG across the sleep-wake cycle, compared to the dramatic modulation in mammals. Some spiking occurred in forebrain leads during sleep, but no change in EEG occurred during periods of rapid eye movement. In "REM" sleep, one eye could be open while the other remained shut. No change in muscle tone occurred during sleep. No arousal threshold testing is described in this brief report. " ...
https://www.semel.ucla.edu/sites/default/files/sleep/pdf/rem-evolution.pdf

"Some REM characteristics have been found in reptiles, including chameleons, desert iguanas and caimans. But the experiments all had problems that have left the question open."...
https://www.dovepress.com/the-influence-of-gravity-on-rem-sleep-peer-reviewed-fulltext-article-OAAP

"they demonstrated that typically brief periods of REM are present while sleeping. Unilateral eye movements with the eyelid opened are also observed without any changes in sleep posture. However, their electroen- cephalographic recordings from the telencephalon suggested no true REM sleep is present. Given the radically di erent anatomy of the lizard brain, recordings from the brain stem (where the structures homologous to those recorded in mammals and birds reside) would be needed to con rm this. In conclusion, neurophysiological studies in reptiles are woefully lacking behind those of other vertebrates and much remains to be investigated." ...
http://www.anthonyherrel.fr/publications/Herrel 2013 Physiology - Chameleon Book.pdf

 

[kinyonga]

There's not much out there about REM in chameleons.

 

[Klyde O'Scope]

" 44 reported evidence for REM sleep in the chameleon lizard. They reasoned that this animal, having very mobile active eyes in waking would be more likely to show eye movement periods during sleep. They, like most subsequent researchers working with reptiles, found relatively little modulation of forebrain EEG across the sleep-wake cycle, compared to the dramatic modulation in mammals. Some spiking occurred in forebrain leads during sleep, but no change in EEG occurred during periods of rapid eye movement. In "REM" sleep, one eye could be open while the other remained shut. No change in muscle tone occurred during sleep. No arousal threshold testing is described in this brief report. " ...
https://www.semel.ucla.edu/sites/default/files/sleep/pdf/rem-evolution.pdf

"Some REM characteristics have been found in reptiles, including chameleons, desert iguanas and caimans. But the experiments all had problems that have left the question open."...
https://www.dovepress.com/the-influence-of-gravity-on-rem-sleep-peer-reviewed-fulltext-article-OAAP

"they demonstrated that typically brief periods of REM are present while sleeping. Unilateral eye movements with the eyelid opened are also observed without any changes in sleep posture. However, their electroen- cephalographic recordings from the telencephalon suggested no true REM sleep is present. Given the radically di erent anatomy of the lizard brain, recordings from the brain stem (where the structures homologous to those recorded in mammals and birds reside) would be needed to con rm this. In conclusion, neurophysiological studies in reptiles are woefully lacking behind those of other vertebrates and much remains to be investigated." ...
http://www.anthonyherrel.fr/publications/Herrel 2013 Physiology - Chameleon Book.pdf

I'm not sure I understand the point (or the tech—this stuff is really outside my ken!) unless to debunk the notion that reptiles (chameleons) dream.
The first citation bears a date of 1999.
The second citation is a quote from a document from 2003.
The third citation references work done in 1966.

The quoted paragraph of the second citation went on to say:

Were they in REM or just awake? Does slower heart rate count as atonia? More studies are needed to determine if REM is active in reptiles.
http://improverse.com/ed-articles/richard_wilkerson_2003_jan_evolution.htm

I think the 2016 study may qualify as one of those "More studies".

As you say, there's not much about chameleons, and what there is is (as I read it) not conclusive.
A few observations:
1. Inconclusivity isn't proof or lack of proof.
2. The 2016 study ostensibly establishes that some reptiles do experience REM sleep, supplanting the previous studies.
3. REM sleep isn't always required for dreaming.

I can concede the question is still pretty much open; the articles about the 2016 study are rife with weasel words. Paraphrasing: "The new study suggests reptiles experience REM sleep, and indicated they may dream."

I still like to keep an open (and optimistic) mind. I expect one day we will know for sure.

 

[kinyonga]

I hope one day we will know for sure and really expect to find out they can/do dream.

 

[Deejay]

My study proves that they have rem and dream. I did a 3-hour sleep recording and my Chameleon looks like a dog dreaming. There is no mistaking it.