Saturday, October 14, 2023

The Lack of Evidence That Brains Produce Dreaming, and Some Evidence Hinting They Don't

In a year 2020 "Dream Catcher" study described here and the scientific paper here, EEG recordings were made of subjects while they were sleeping. The subjects were awakened at random times, and asked to state whether or not they were dreaming.  Then some scientists ("blind" to which EEG reading were from the dreamers) were asked to guess whether particular subjects were dreaming. The result was a null result. There was no evidence that by studying EEG recordings you can tell whether a person is dreaming.  

Scientists apparently delayed the release of these results for years. A 2015 paper describes results just like those of the Dream Catcher study, but results that had apparently not yet been published:

"When data from serial awakenings of 9 subjects had been collected, these data were divided. Introspective reports and electroencephalographic recordings were analysed by different judges who were ignorant of which EEG sequences had led to dream reports and which ones had not. An external EEG research group used a number of statistical methods to identify the signature of the recordings that were followed by dream reports. But the accuracy of their predictions turned out to be no better than chance. A doctoral researcher presenting these findings at a conference explained that there were 4 different explanations for this failure: ‘Subjective experience is a) not in the brain, b) is in the brain, but not in the EEG, c) is in the EEG, but not in our data, or d) is in the data, but needs more complex and novel methods of analysis.’" 

The paper then quotes someone from 2008 saying this:

"We still haven’t found any objective sign indicating the presence or absence of consciousness in the dreaming brain. Maybe that’s something that Descartes would have predicted: that you cannot objectively capture consciousness because it is this immaterial, non-spatial, and imperceptible thing ... We haven’t been able to disprove the Cartesian position ... The dream catcher experiment is a test of the whole emergent materialist position ... We will continue our analysis, but if we can’t find anything then we have a real problem where to go."

The result suggested the brain is not the source of our dreams. There is another reason for thinking such a thing. There is no robust evidence that removing or damaging some part of the brain causes a cessation of dreaming. The paper "Dreaming and REM sleep are controlled by different brain mechanisms" is an example of one of the countless neuroscience papers that make claims not established by the research that is cited. The paper claims "Dreaming is eliminated by forebrain lesions which completely spare the brain stem."  The paper claims that "108 further cases with complete (or nearly complete) loss of dreaming in association with focal forebrain lesions have been published."  The use of the phrase "or nearly complete" should alert us that no good evidence has been given that "dreaming is eliminated by forebrain lesions."  The claim of 108 cases referred to were cherry-picked from dozens of papers that each mentioned only a few cases; but neuroscientists often make incorrect citations claiming that papers said things the papers did not show or state. The paper does not even give the titles of the papers it claims contained such cases. The paper then claims that dreaming is lost by damage near the "parieto-temporo-occipital (PTO) junction."  But a 1985 paper "Dream Recall After Sleep Interruption in Brain-Injured Patients" had found successful dream recall in  6 out 8 brain-damaged patients that were identified as having lesions in just such a "parieto-temporo-occipital" region (Table 1). 

A 2004 press release is entitled "The (Brain) Stuff Of Which Dreams Are Made." It describes a case of a woman who had a stroke, and then reported she no longer dreamed several times a week, as she did before. The story is referred to by a 2015 Psychology Today article, as if it was evidence that brains create dreams. What the Psychology Today article fails to mention is that the press release had told us that the woman's dreaming ability returned, with dreams occurring as often as once a week. The facts in the 2004 press release are misrepresented by the Psychology Today article, which falsely tells us "her vision issues improved after several days, but her dreaming remained suspended." 

Another example of the literature misleading us is a 1951 paper entitled "Cessation of Dreaming After Brain Injury." The paper reports three cases of brain injury, and in two of them there was actually no "cessation" but merely a self-reported reduction in dream activity. In one of the three cases someone reported a complete cessation of dream activity. But we don't know how accurate such a report was. A 2014 paper tells us that "the inability to recall dreams and the loss of dream experience are rare in stroke patients," something we would not expect if brains produce dreams.  

Anecdotal reports of dream cessation are not very reliable, and papers reporting dream cessation after brain damage tend to have unreliable standards for reporting such a cessation. Someone may be asked "Do you recall any dreams you recently had?" and the answer may be "no."  Such a person may then be described in a paper as someone who lost his ability to recall dreams, even though no good evidence yet exists the person has had such a loss.  We can imagine something like this sometimes occurring:

Neurologist: So can you recall any dreams you had last night?
Patient: No. 
Neurologist: Well, I'm real interested in people with brain damage who can't recall dreams, because that helps to show that the brain causes dreaming. Can I put you down as one of those people?
Patient: Sure. Whatever. 

Memories of dreams usually fade very rapidly, so asking someone whether they recall dreams (at a time 30 minutes or more after they woke up) in not a reliable way of judging whether they are dreaming. The only reliable way to test whether someone has lost dreaming ability is to do something a lot more rigorous, like waking someone up many different times at random intervals (preferably after REM activity had been detected), and to immediately ask whether he recalled having any dream that night. If such a test failed after 30-different sudden wake-up events on ten different nights, that might be good evidence that the person had lost the ability to dream.  But I doubt whether a test as rigorous as this has been applied to most of the people described as brain damaged people who lost the ability to dream. 

A 2017 paper was entitled "The Neural Correlates of Dreaming." The paper was disputed by a 2020 commentary entitled "The Neural Correlates of Dreaming Have Not Been Identified Yet. Commentary on 'The Neural Correlates of Dreaming. Nat Neurosci. 2017.' "

No one has ever given a credible account of any natural reason why humans would have developed the ability to dream, something that has no survival value or reproduction value. Accounts that attempt to describe biological reasons for dreaming are usually examples of mere hand waving. Studies cited to support the claim that dreaming helps consolidate memories are typically bad examples of junk science. For example, we often get people claiming that rodent studies have suggested an idea, with a reference to the paper "Reactivation of Hippocampal Ensemble Memories During Sleep." But the paper seems like p-hacking science shlock, as it  involves a way-too-small study group size of only 3 rodents, and reporting unimpressive statistical significance of merely p < 0.05. 

There have been some studies that had people in a lab engage in some video game task in the hour before falling asleep, and then had the subjects woken up at various times at night to be asked about what they were dreaming about. It was claimed that the people dreamed more frequently about the task they had done before sleeping,  but anyone being a subject in such a study might tend to interpret dreams as having some relation to some task he did before sleeping, knowing or suspecting that this was the result desired by the scientists. Claims of better performance by those who dreamed of the task are unimpressive, involving small study group sizes and unimpressive statistical significance.  

My own personal experience is that for the past three years I have been playing video games for about an hour in the ninety minutes before sleeping, and I have also been also been rigorously recording my dreams during the past three years, recording them at night on a notepad just after awaking after the numerous random times during the night in which I would wake up. My very extensive account of such dreams is here. Among the thousands of dreams I have recorded during these three years, there never seemed to be a single dream in which I was replaying or rehearsing any of the tasks that were occurring in a video game I had played, nor did there ever seem to be a single dream that contained any of the content or characters or challenges of the video games I was playing.  Based on this experience, I am very skeptical of all claims that dreaming serves to consolidate memories. 

What I have seen after three years of recording most of my dreams is an effect completely at odds with claims that dreams are random content produced by the brain.  During the past three years my dreams have very strongly seemed to express thematic content, with more than 400 dreams seeming to suggest themes of life after death.  There is another very meaningful theme that has occurred more than 300 times in my dreams, one I have not listed in my published dream log, because it is too personal to make public. That theme is also related to life after death.  Counting dreams I have listed as related to life after death in my published dream log, and 300 additional dreams also related to life after death that I have not published, the total number of dreams I have had in the past three years that seemed to refer to life after death (often through symbolism) is in excess of 700. In addition to such dreams, I have also had over 600 dreams of deceased people during the past three years. Besides such dreams I sometimes have dreams with extremely subtle and sophisticated philosophical concepts, dreams that leave me thinking "such a dream could not have come from a sleeping brain." 

There has been considerable evidence (experimental or anecdotal) for telepathic effects or clairvoyant effects occurring during dreaming.  You can read here about some of the laboratory evidence for ESP during dreaming, which was mainly collected at the Maimonides laboratory in the 20th century.  The meta-analysis here finds highly significant evidence for ESP during dreaming.  Such evidence is inconsistent with claims that dreams are products of the brain. All evidence of ESP is evidence against claims that the brain is the source of the mind, as no one can conceive of how telepathy could occur by any action of the brain.  That is part of the reason why we see such a strong effect in academia of psi denialism, in which professors stubbornly deny two centuries of strong evidence for psi effects such as ESP,  including very strong laboratory evidence gathered in the past hundred years (some examples are discussed here, here and here). 

There are many cases of dreams seeming to foretell a death, as I describe in my posts here, here and here.  A reasonable hypothesis consistent with such reports is the idea that when people get old or come within a few years of death, they may start to get content in their dreams alerting them (often through symbolism) of the transition ahead of them, in which they will go from this earthly realm to some afterlife realm.  My dream experience during the past three years has strongly supported such a hypothesis.  The evidence for ESP during dreams is consistent with such a hypothesis. A dreaming mind may get dream content through ESP from residents of some afterlife realm.  To further substantiate such a hypothesis, more old people or dying people should keep long-term dream logs like those I have kept.  There have been some studies done  on dreams of the dying, which tend to support or be consistent with the hypothesis I mentioned.  But such studies have usually been affairs in which people in hospices were simply asked what dreams they remembered.  A more vigorous way to study the topic is to have older people maintain long-term dream logs, in which they write down on a notepad all dreams while waking up in the middle of the night, and then publish the results, while trying to categorize what they think the dreams suggest. 

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