Why do we dream? A new theory on how it protects our brains • Hacker News Board

Re: Why do we dream? A new theory on how it protects our brains

#91

Post by agumonkey » Fri, Jan 01, 2021, 2:32 PM UTC

FailMore wrote: post #79

This idea ignores a fascinating aspect of REM sleep. During REM, the brain shuts down the executive functions, while the brain goes into extreme 'story generation mode'. A story in which you are a character. I think this is one of the most overlooked and interesting parts of dreaming. We are able to observe ourselves in our dreams acting without the constraints of our 'executive functioning' brain. This means we get…

Makes me wonder when did animals started to dream, even prototypcally.

Mammals ? Reptiles ?

Re: Why do we dream? A new theory on how it protects our brains

#92

Post by sundarurfriend » Fri, Jan 01, 2021, 2:38 PM UTC

> dreams are primarily visual precisely because ...

This is a central claim in the article that's just stated and taken for granted.

In my experience, at least, dreams are not primarily visual. They have a visual component, but also a vague auditory component, a motor-experience (feeling of movement) component, etc., and all of those feel equally important. And most of all, there is a "felt experience" component that actually feels like the primary element of it; emotion is the core element of that, but a better description is "the lizard brain's interpretation" of what's happening in the dream, that feels like the central element of the dream.

The visual part is also not in full colour generally, in my case, it's like early movies during the transition from black-and-white, with slight colour tints generally towards the bluish colour regions.

I'm curious what others' dream experiences are like, and in particular whether it's the case that most people do experience them as primarily visual.

Re: Why do we dream? A new theory on how it protects our brains

#93

Post by sundarurfriend » Fri, Jan 01, 2021, 2:41 PM UTC

FailMore wrote: post #79

This idea ignores a fascinating aspect of REM sleep. During REM, the brain shuts down the executive functions, while the brain goes into extreme 'story generation mode'. A story in which you are a character. I think this is one of the most overlooked and interesting parts of dreaming. We are able to observe ourselves in our dreams acting without the constraints of our 'executive functioning' brain. This means we get…

I think the article describes one good reason for why we dream, one of the benefits of dreaming, but it doesn't have to be the only or even main reason. I think it's most likely that dreaming provides multiple benefits, and what the article claims is one of the minor ones.

Re: Why do we dream? A new theory on how it protects our brains

#94

Post by LinuxBender » Fri, Jan 01, 2021, 2:42 PM UTC

ben_w wrote: post #82

syrrim wrote: post #11

This doesn't explain why consistently interrupting REM sleep will lead to death. Also, the exposition suggests that this is somehow particularly necessary for visual information because we can't see while sleeping. They originally suggest that this is because it's dark at night, but later modify it to be because one's eyes are closed while sleeping. However, to my knowledge, very little hearing is done while one is s…

> consistently interrupting REM sleep will lead to death. I’ve seen this claim many times, but I’ve not seen any studies that say “no [REM] sleep causes you to die”. The closest I can find are studies in the form “less [REM] sleep correlates with all causes of death to go up” - it’s not like you can literally kill someone just by keeping them awake for a month. https://www.nhlbi.nih.gov/news/2020/study-links-poor-dre…

I don't have a link handy, but I recall watching a documentary where a bunch of college students participated in a study that involved waking them every time they reached REM state. After 6 days they started becoming psychotic. After 7 days someone stepped in and aborted the project as the students were going fully psychotic. I don't recall who intervened. They may not have died but if I recall correctly, they would have killed each other.

Re: Why do we dream? A new theory on how it protects our brains

#95

Post by seesawtron » Fri, Jan 01, 2021, 2:45 PM UTC

Link to original paper which is still a non-peer reviewed biorxiv article [0]. The crux of the paper is based on expressions of plasticity correlating with the percentage of sleep time spent in REM (fig.2). Apart from the high-level questions raised already in the comments there are several caveats in the data:

    Data points are sparse i.e. the number of samples included are too few to strongly believe in correlations. Taking out extreme data points would make the correlations look independent.

    The data values across 25 primate species are based on averages across previous studies and using proxies where some data was not available. I do not know how justifiable such approaches are but I am skeptical about them.

[0] https://www.biorxiv.org/content/10.1101/2020.07.24.219089v1....

Re: Why do we dream? A new theory on how it protects our brains

#96

Post by agumonkey » Fri, Jan 01, 2021, 2:52 PM UTC

sundarurfriend wrote: post #92

> dreams are primarily visual precisely because ... This is a central claim in the article that's just stated and taken for granted. In my experience, at least, dreams are not primarily visual. They have a visual component, but also a vague auditory component, a motor-experience (feeling of movement) component, etc., and all of those feel equally important. And most of all, there is a "felt experience" component that…

To me the most peculiar aspect of dreams is how vivid the universe you're in is. It feels as emotionally impactful as the best moments of your life. Super weird

Re: Why do we dream? A new theory on how it protects our brains

#97

Post by EugeneOZ » Fri, Jan 01, 2021, 2:56 PM UTC

silverpepsi wrote: post #83

EugeneOZ wrote: post #70

Earlier quoted context omitted.

You and they making a mistake saying that blind people should not see dreams. I wonder how such an idiotic idea reached the HN at all. It's Daily Mail level. People see dreams not every time they sleep, not every night, sometimes we can have multiple nights without dreams. By this moronic theory our “visual cortex” should be modified to “blind mode” just in the first night of sleep without dreams. Articles containing…

I would recommend rereading the article, your reading comprehension wasn't up to par to tackle it in one pass. Also you're assuming a TON of things that were never suggested. Jumping to conclusions won't help you read what was written I'd say

Quote where I’m wrong or don't start it. Just saying “a TON of things” without a single example is ridiculous.

Re: Why do we dream? A new theory on how it protects our brains

#98

Post by bjornsing » Fri, Jan 01, 2021, 2:58 PM UTC

I don’t buy it. Dreaming is computationally/metabolically expensive. If the sole purpose was to prevent plasticity then there would be far cheaper ways to accomplish the same result.

Re: Why do we dream? A new theory on how it protects our brains

#99

Post by EugeneOZ » Fri, Jan 01, 2021, 2:59 PM UTC

silverpepsi wrote: post #81

EugeneOZ wrote: post #26

So by their theory blind people don't need to sleep? Total bullshit.

Well, why are you implicitly insisting on the unproven theory that "sleep serves just one single purpose" - one that no one else has proposed? What if sleep is needed for more than one reason? Is the complexity of the world so hard to fathom that you throw up your hands and yell 'bullshit' on the first hint of challenge!

Lol. Please quote where I’m saying this. I never wrote that phrase you quoted in your comment. Are you trying to lie? :)

Better read my words one more time:

“People see dreams not every time they sleep, not every night, sometimes we can have multiple nights without dreams. By this moronic theory our “visual cortex” should be modified to “blind mode” just in the first night of sleep without dreams.”

Clearly “your reading comprehension wasn't up to par to tackle it in one pass” ;)

Re: Why do we dream? A new theory on how it protects our brains

#100

Post by krapp » Fri, Jan 01, 2021, 3:06 PM UTC

agumonkey wrote: post #96

sundarurfriend wrote: post #92

> dreams are primarily visual precisely because ... This is a central claim in the article that's just stated and taken for granted. In my experience, at least, dreams are not primarily visual. They have a visual component, but also a vague auditory component, a motor-experience (feeling of movement) component, etc., and all of those feel equally important. And most of all, there is a "felt experience" component that…

To me the most peculiar aspect of dreams is how vivid the universe you're in is. It feels as emotionally impactful as the best moments of your life. Super weird

The same brain that simulates your entire perception of reality from external inputs is using all of its resources to simulate its own, with itself as an input.

What's really weird is how dream-reality always makes sense to you in context, regardless of how absurd or random it is, because your self awareness and identity are being simulated the same way, both in dreams and in reality. It's like a virtual machine inside a virtual machine.