A cardiologist is a specialist in hearts and the human circulatory system. You can trust a cardiologist to speak accurately about how hearts work and what hearts do. For example, if a cardiologist tells you that hearts normally beat about 60 times a minute when people are resting, and often more than 100 times a minutes when people are running, you can trust that this statement is correct. One of the reasons we can trust cardiologists to speak accurately about hearts is that cardiologists are not members of a belief community. There is no set of dogmas that you are indoctrinated in if you train to become a cardiologist.
But in regard to neuroscientists, we have a vastly different state of affairs. Neuroscientists are members of a belief community that we can call the NBC, the Neuroscientist Belief Community. Just as the members of some church share some particular articles of faith, neuroscientists share a set of dogmatic belief tenets that make up a creed. The two main dogmas of this creed are:
(1) the belief that the human mind is merely the product of the human brain, or perhaps that the human mind merely consists of particular brain states;
(2) the belief that human memory is a product of the human brain -- that memory creation involves some act of storage going on in the brain, and that memory recall involves the retrieval of information stored in the brain.
Because neuroscientists are members of a belief community that adheres to these dogmatic tenets, very much like church members clinging to some creed, we should not have a simple, uncomplicated trust in the accuracy of neuroscientists when they speak about brains and minds. In particular:
(1) whenever neuroscientists talk about the cause of mental phenomena and attribute such phenomena to brains, we should be suspicious about whether their statements are accurate;
(2) we cannot even have high confidence when neuroscientists speak about how brains behave;
(3) we cannot have high confidence in the accuracy of neuroscientists when they generalize about the type of mental experiences that people have.
The reasons why we should have such a lack of confidence include the following:
- In general, neuroscientists are very often not very thorough or deep students of human minds and human mental experiences, a topic of oceanic depth. Part of the reason is that getting a neuroscience PhD does even require a deep study of the human mind and human mental experiences. You can look at the required courses needed to get a master's degree in neuroscience, and you will see that such courses involve very little study of the human mind and human mental experiences (often as little as one or two courses in psychology).
- The statements of neuroscientists are very strongly biased by their desire to propagate and bolster the belief tenets of the belief community they belong to. So when neuroscientists attempt to generalize about things such as memory and creativity, they will often be giving us little sermons that preach to us the central dogmas of the creed of their belief community.
As Exhibit A backing up the title of this post, I refer you to a recent NPR article entitled "7 surprising facts about dreams — why we have them and what they mean." We have an interview with neuroscientist Rahul Jandial, who makes some statements that are inaccurate or poorly supported.
First, we have this generalization that is incorrect:
"'Reports of nightmares and erotic dreams are nearly universal,' Jandial says, while people rarely report dreaming about math. Jandial says the lack of math makes sense because the part of your brain primarily responsible for logic — the prefrontal cortex — is typically not involved in dreaming."
There is no good basis for claiming that logic comes from the brain, or from any particular part of the brain. See my post "Reasons for Doubting Thought Comes from the Frontal Lobes or Prefrontal Cortex" for relevant facts and reasons. All regions of the brain are continually firing electrical signals, regardless of whether someone is awake or dreaming. So the idea that the prefrontal cortex is electrically inactive during dreaming is incorrect. The prefrontal cortex is just as active as any other region during dreaming.
As for the idea that people don't dream about math or don't use logic in dreams, that is incorrect. I have for years recorded my dreams. I get numbers and number themes very frequently in my dreams. I have had many dreams involving complex math and philosophical topics. Several of my dreams dealt very explicitly with the extremely mathematical and philosophical topic of the fine-tuning of the universe's fundamental constants, and in some of these dreams I recalled and mentioned at least one specific mathematical fact relating to such a topic. In the dream accounts here (made from notes I took at night just after the dream), on the highly philosophical topic of whether very complex biological organization can be naturally explained, I recalled correctly the rough number of types of protein molecules in the human body (20,000), and also the rough number of types of cells in the human body (about 200), and used such facts as part of subtle complex logic. In another dream mentioned in that post, I used mathematical reasoning to back up claims I was making about the evidence for ESP. Just yesterday I had a dream involving people trying to compute the area of a rectangle with a big circular hole in its center, and I said in the dream "you'll probably end up using pi," and even recalled that pi is 3.14. My mathematical guess in the dream was correct; pi is used as part of the solution of such a problem (given in the Appendix of this post). My dreams very frequently refer to philosophical themes such as life after death.
In Section 2 of the NPR post, we have the unbelievable claim that neuroscientist "Jandial learned something fundamental about dreams in the midst of performing brain surgery." We are told that during brain surgery done on a conscious patient "after one zap of electricity, Jandial’s patient experienced a nightmare that had recurred for him since childhood." The NPR story attempts to pass this off as some evidence that brains produce dreaming. It makes no sense, because the patient wasn't dreaming, but was awake. And you don't prove that X causes Y because of one case in which X and Y happen at the same time. Having open-brain surgery while awake (something like vivisection) and being zapped with electricity at the same time would for many people be a nightmarish experience. For someone to recall a recurrent nightmare he had during such a nightmarish brain surgery is something we might expect regardless of whether brains produce dreams.
We then have a mixture of a false claim from the article writer, and a misleading claim by Jandial:
"Research has since confirmed that nightmares, and all dreams, arise from brain activity. 'Now we know from different measurements of electricity and metabolic usage, the sleeping-dreaming brain is burning hot. It's sparking with electricity. We might be asleep, but the brain is on fire,' Jandial says."
No, brains don't get hotter during sleeping or dreaming, nor does neural electricity increase. Research has not confirmed that dreams are produced by brains. For related evidence, see my post "The Lack of Evidence That Brains Produce Dreaming, and Some Evidence Hinting They Don't." In a major study called the Dream Catcher study, discussed here, scientists looked at EEG readings taken just before sleeping patients woke up, and were asked about whether they were dreaming when awoken. Scientists tried to predict from the EEG readings whether subjects were or were not dreaming, based on the EEG readings. Their predictions were not better than chance. The study provided evidence clashing with the claim that your brain produces dreams.
We then have an important-sounding statement by Jandial that is the exact opposite of the truth. He states this:
"Jandial says there’s evidence that death may come with one final dream. 'Once the heart stops, with the last gush of blood up the carotid [artery] to the brain, the brain's electricity explodes in the minute or two after cardiac death…Those patterns look like expansive electrical brainwave patterns of dreaming and memory recall,' Jandial says."
What Jandial claims here is the exact opposite of the truth. When the heart stops, instead of "exploding" in the sense of greatly increasing, the brain electrical activity very quickly dies away and flatlines, trailing off to a flat line usually within about 10 or 15 seconds. For a discussion of some neuroscience papers that deal with this subject, and show parallel graphs of heart activity and brain wave activity when the heart stops, see my post here.
The term "isoelectric" or iso-electric in reference to brain waves means a flat-lining equivalent to no electrical activity in the brain, as measured by EEG readings. The paper here states, "Within 10 to 40 seconds after circulatory arrest the EEG becomes iso-electric." Figure 1 of the paper here says that such an isoelectric flat-lining occurred within 26 seconds after the start of ventricular fibrillation, the "V-fib" that is a common cause of sudden cardiac death, with "cortical activity absent." Also referring to a flat-lining of brain waves meaning a stopping of brain electrical activity, another scientific paper says, "several studies have shown that EEG becomes isoelectric within 15 s [seconds] after ischemia [heart stopping] without a significant decrease in ATP level (Naritomi et al., 1988; Alger et al., 1989)." Another paper tells us this about brain waves and infarction (obstruction of blood flow), using CBF to mean cerebral blood flow:
"When normal CBF declines, the EEG first loses the higher frequencies (alpha and beta bands), while the lower frequencies (delta and theta bands) gradually increase. When the CBF decreases further towards an infarction threshold, the EEG becomes isoelectric."
This is the exact opposite of what Jandial asserted. Similarly, another paper refers to blood pressure, and tells us, "When flow is below 20 mL/100 g/min (60% below normal), EEG becomes isoelectric." meaning that brain electrical activity flat-lines. The 85-page "Cerebral Protection" document here states, "During cardiac arrest, the EEG becomes isoelectric within 20-30 sec and this persists for several minutes after resuscitation." Another scientific paper states this:
"Of importance, during cardiac arrest, chest compliance is not confounded by muscle activity. The EEG becomes isoelectric within 15 to 20 seconds, and the patient becomes flaccid (Clark, 1992; Bang, 2003)."
Similarly, another paper A 2017 paper was "Electroencephalographic Recordings During Withdrawal of Life-Sustaining Therapy Until 30 Minutes After Declaration of Death." That 2017 paper studied the brain waves of four humans who died in Ontario, Canada after their hearts stopped. The paper stated, "We also did not observe any well-defined EEG states following the early cardiac arrest period as previously reported in rats." No "well-defined EEG states" means the same as no brain electrical activity. Similarly, a recent paper referring to EEG readings of brain waves states this: "The trajectory of EEG activity following cardiac arrest is both well defined and simple. It consists of an almost immediate decline in EEG power, which culminates in a state of isoelectricity [flatlining] within 20 s [seconds]."
Do a Google search for "EEG becomes isoelectric" or "EEG becomes iso-electric" and you can find quite a few other papers saying that brain waves (as measured by EEG) become isoelectric (in other words go flat or flat-line or die off) within about 20 seconds after a heart stops, or as soon as blood pressure falls below about 50% of normal.
As for Jandial's claim about "expansive electrical brainwave patterns of dreaming and memory recall" there are no such brain wave patterns that tell when dreaming or memory recall is occurring. When people dream and recall, their brains do not have any kind of unusual or distinctive brain wave activity that allows you to distinguish such states. There is no distinctive neural correlate of either dreaming or recall. That's one reason the Dream Catcher study mentioned above produced only a null result, with scientists being unable to predict whether the subjects had been dreaming before they were awaken. For a discussion of the lack of any evidence that there is any such thing as distinctive brain patterns of memory recall, see my posts here, here and here.
The glaring misstatement Jandial made about an explosion of electrical activity in the brain after the heart stops (totally contrary to the observed facts) is similar to misstatements made by another neuroscientist, misstatements I debunk in my post here. A search for Jandial's scientific papers on Google Scholar shows very many intelligent-looking papers relating to the brain and neurosurgery, which make him sound like a good reliable doctor; but I can't find any paper by him about dreaming. A Google Scholar search for "Rahul Jandial+dreams" produces no relevant papers. So I'm baffled by why NPR would be trying to present Jandial as some expert on dreaming. What we should remember is that in general most neuroscientists are not very careful scholars of human minds and human mental experiences, a topic of oceanic depth. The academic science involving the study of human minds and human mental experiences is not called neuroscience; it is called psychology. You don't have to study much psychology to become a neuroscientist or a neurosurgeon.
In an article in the Guardian, Jandial gives us an account of dreaming that is not accurate:
"Dreams are the product of profound changes the brain automatically undergoes each night. The rational, executive network in the brain is switched off, and the imaginative, visual and emotional parts are dialed way up. As a result, the dreaming mind is given free rein in a way that has no parallel in our waking lives. We couldn’t think this way when we are awake even if we tried."
Not true. The brain does not undergo any profound change when you are in bed. I record my dreams at night, typically several times a night at different intervals during the night, and I experience normal rational mentality the instant I wake up, as I do while recording my dreams in darkness, and then thinking about what I have recorded, typically for quite a few minutes. My rational mind ponders calmly and thoughtfully numerous times during the night. And people can think in imaginative dream-like ways when they are awake, as creative writers and daydreamers often do.
In an interview Jandial offers a nonsensical-sounding account of why we dream. He states this:
"Why do we dream? The brain’s activity during dreams suggests it’s preserving or cultivating something essential. Some theories propose dreams as a form of threat rehearsal or a nocturnal therapist. I believe it’s more fundamental: similar to the ‘use it or lose it’ principle that applies to muscles, our brains engage in a nightly routine that stimulates thoughts and ideas not typically relied upon during the day. This built-in process keeps our thinking adaptive and nimble, fostering divergent thoughts and offering an evolutionary advantage. That’s the broader concept I’m exploring."
The explanation makes no sense at all. Dreams do not have any survival value, and cannot be explained as offering some "evolutionary advantage." Theories of why we dream are "a dime a dozen." As one scientist said in 2022, "I don’t think there’s a consensus on what dreaming is, why we dream, what we do, what the function of dreaming is, or even if there is a function." Jandial has written a book entitled "This Is Why You Dream." Such a title is a great example of the explanatory hubris of neuroscientists. Once again, we have a neuroscientist pretending to know something he does not know. No scientist understands why people dream, and Jandial does not sound at all like anyone with a credible theory of why dreams arise. Also, it is not true that "the brain’s activity during dreams suggests it’s preserving or cultivating something essential," because experimental studies trying to suggest this idea are in general poorly designed studies guilty of Questionable Research Practices such as way-too-small study group sizes.
The idea advanced by Jandial that dreaming is a product of random brain activity is very much contrary to my own experience, which is several consecutive years of dreams with meaningful content that is strongly thematic, being overwhelming centered upon a philosophical theme of life-after-death. You can read about such dreams in my post here.
In a Salon interview, Jandial is asked why we dream, and he says, "The fundamental principle of neurons, neural tissue, is that either you use it or you lose it." No, actually, totally contrary to such a claim I rode a bike very well when I tried to ride a bike after not riding a bike for ten years, and I could drive well after not driving for ten years. There is no strong evidence of mental inactivity being a big cause of neuron loss. And people are often amazingly good at remembering things they learned or experienced decades ago and never thought about in the intervening years, contrary to such a "use it or you lose it" claim. Jandial has no credible story to tell in the interview regarding why people dream. In the same interview Jandial again makes the utterly untrue claim that an "explosion of brainwaves happens in the minute or two after the cessation of electrical activity on EKG," which is the opposite of the truth, as I show above (what actually happens is that brainwaves flatline -- become isoelectric -- within 20 seconds after " the cessation of electrical activity on EKG," the same as the heart stopping).
In the same interview Jandial also makes the untrue claim that in the one or two minutes after the heart stops the brain "explodes with neurotransmitters." There is no good evidence that neurotransmitters appear more frequently after a heart stops, and the very strong evidence we have of the quick cessation of brain electrical activity upon a heart stopping is a strong reason for thinking no such increase in neurotransmitters occurs. The untruth of Jandial's claim here should be obvious when you consider that there is no device capable of measuring human neurotransmitter increases or decreases in the minutes after a heart stops. Neurotransmitters are measured by blood or urine tests, which are never done at the moment of death, and which require lab work.
Mind activity varies vastly, but brain activity (as measured by EEG and fMRI) is remarkably stable (unlike heart activity that varies by 200% or more). The lack of big changes in brain activity corresponding to changes in mental activity is one of many reasons for thinking that brains are not the source of minds. There is only one time when brain activity very sharply spikes: during the "electrical storm" events called seizures. If you're not talking about seizures or fevers and you're not talking about military destruction, you should not be using any language like that in the visual above. Brain imaging visuals typically involve misleading depictions of brain activity differences of less than 1%, differences so small they cannot be accurately described as some region of the brain "lighting up."
Neuroscientists have an enormously bad speech habit regarding how they describe the activity of humans. The habit consists of senselessly claiming brains were the source of things that we only know came from people, things which cannot credibly be explained as brain-caused. So we have neuroscientists senselessly speaking like this:
- Instead of saying "people can recall things very quickly" a neuroscientist will say something like "brains can recall things very quickly."
- Instead of saying "people can solve hard math problems," a neuroscientist will say something like "brains can solve hard math problems."
- Instead of saying "people have strong beliefs about politics" a neuroscientist will say something like "brains can have strong beliefs about politics."
- Instead of saying "a person has a unified sense of the self," a neuroscientist will say something "the brain gives rise to a unified sense of the self."
- Instead of saying "you use facts to guide your decisions," a neuroscientist will say something like "your brain uses facts to guide its decisions."
- Instead of saying "someone may recall an experience from long ago," a neuroscientist will say something like "a brain may recall an experience from long ago."
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