Neuroscience research often involves risks to human subjects involved in that research. Different types of research involve different types of risk.
fMRI Risks
Many patients undergo medically unnecessary scanning in fMRI machines, purely for the sake of neuroscience research. Such scans involve substantial risks, which are discussed in my post "Poorly Designed Brain Scan Experiments Needlessly Put the Needy at Risk." One danger of fMRI scans is well-known: the risk of the very strong magnets used by such machines causing some metal object to be hurled at a high speed, causing injury or death. In 2001 a six-year-old boy was killed in the US during an fMRI scan, when the machine turned an oxygen canister into a flying projectile. There is always a risk of lingering psychological trauma when certain people are put in some noisy high-tech machine and told they must be silent and not move for a long time such as an hour. There is also the risk that the more powerful fMRI scans (and longer fMRI scans) may raise the risk of cancer in the person getting getting the scan.
The 2009 study here ("Genotoxic effects of 3 T magnetic resonance imaging in cultured human lymphocytes") cautions about the use of a high-intensity ("3T and above") fMRI, and states that "potential health risks are implied in the MRI and especially HF MRI environment due to high-static magnetic fields, fast gradient magnetic fields, and strong radiofrequency electromagnetic fields," also noting that "these results suggest that exposure to 3 T MRI induces genotoxic effects in human lymphocytes," referring to effects that may cause cancer. There are very few studies comparing cancer rates in those who have had fMRI scans and those who have not had such scans. Now neuroscientists are starting to do neuroscience experiments on humans with more powerful fMRI scanners such as 7T scanners, which have potentially higher risks. So claims by scientists that "fMRI scans are safe" are not candid about risks. It is entirely possible that every time someone has a long fMRI scan (as often done for neuroscience research) that he is increasing his lifetime risk of getting cancer.
Claims that "fMRI scans are safe" are typically claims made based on short scans (such as 10 minutes) with 1.5T and 3T scanners, not claims based on hour-long scans often done in neuroscience research, and not claims based on scans with the higher-intensity 7T scanners. Neuroscience researchers often ask subjects to engage in multiple long scans, with the total scanning time as high as 3 hours or more. See here for an example in which subjects were unnecessarily scanned for almost 3 hours, and here for a poor-quality study in which subjects were unnecessarily scanned for 16 hours in a 3T MRI scanner. See here for a discussion of how subjects were scanned unnecessarily for 38 hours each in a 7T scanner (described as "ultra-high magnetic strength") to create an unnecessary database (of very dubious usefulness) tracking nothing other than how brains look when people were looking at different natural scenes.
Scientists do not track the long-term health of subjects they have subjected to long fMRI scans. Their rule is "scan them and forget them." It often happens that things that were once not thought to be carcinogenic are later shown to be carcinogenic. For example, today I read that the US surgeon general is saying alcohol uses causes 20,000 deaths a year in the US. In the high school I attended students were forced to dissect cats, and the dead cats were stored in a vat of formaldehyde, which often got on the students' skin. We now know formaldehyde is a carcinogen.
When we examine the history of fMRI scans, we see a history of overconfidence, and authorities dogmatically asserting that "fMRI scans are perfectly safe," when they did not actually know whether they were perfectly safe. Not many years ago there arose the great "contrast agent" scandal. Scientists began to learn that what are called "contrast agent" fMRI scans may not be so safe. In such "contrast agent" scans, a subject is given an injection that increases the visual contrast of the fMRI scan. For a long time, the main substance in such an injection was gadolinium. A mainstream cancer web site states, "Tissue and autopsy reports have also confirmed that gadolinium can accumulate in the brain and other organs." The results can be a health disaster, as described here. A 2019 Science Daily story says, "New contrast agent could make MRIs safer," letting us know that many of them previously were not so safe. On the same Science Daily web site, we read a 2017 news story with the title "MRI contrast agents accumulate in the brain." A 2020 paper ("Side Effect of Gadolinium MRI Contrast Agents") says this:
"Until recently, it was believed that gadolinium is effectively cleared within 24 hours after intravenous injection, and that it does not have any harmful effects on the human body. However, recent studies on animals and analyses of clinical data have indicated that gadolinium is retained in the body for many years post-administration, and may cause various diseases."
Neuroscientists extensively used such contrast agents (as described here), very often putting human subjects at risk. typically for the sake of junk poorly designed studies falling far short of the best experimental practices. You can do a Google search for "gadolinium deposition" to learn more about this issue.
The University of North Carolina publishes a template for an "Adult Consent Form" informed consent form, and the template has the selection below. I will boldface and underline two lines:
"As part of the MRl procedure you may receive a dye called gadolinium. Gadolinium makes it easier to see details on the MRI pictures. If you have any problems with your kidneys, you may be at risk for a condition called Nephrogenic Systemic Fibrosis or Nephrogenic Fibrosing Dermopathy (NSF). NSF has been reported to occur between 2 days and 18 months following injection of gadolinium. There is no known treatment for NSF. Some people have even died from this. Signs and symptoms of NSF may include: burning, swelling, hardening or tightening of the skin, blood vessels and internal organs (heart, lungs, live; yellow spots on the white part of the eyes; joint swelling and stiffness; pain in the hip bones or ribs; muscle weakness."
Probably the great majority of people who underwent fMRI scans for neuroscience research and who ingested gadolinium were not informed so candidly about the risks, and only in later years did language so candid tend to commonly appear in such forms.
Invasive Electrode Implantation Risks
Electrodes may be implanted in the brains of epilepsy patients to help determine the best way to do surgery for epilepsy. But the same person involved in doing such surgery may be doing neuroscience research, and may try to take advantage of the opportunity offered by implanting electrodes in a patient's brain. That person may cause additional electrodes to be implanted in the patient's brain, electrodes that were not necessary for surgery evaluation. All electrode implantation comes with risks.
A paper tells us the following:
"A meta-analysis of 2542 patients implanted with subdural grids for extraoperative monitoring prior to epilepsy resection, both with and without depth electrodes, the estimated pooled prevalence of pyogenic central nervous system infection was 2.3%, of intracranial hemorrhage was 4.0%, and of transient new neurological deficits was 4.6%, with 3.5% of patients requiring additional surgical procedures to manage adverse events.23 Similar complication rates were reported from a national hospital database in addition to an estimated 11.7% rate of cerebrospinal fluid leakage, a complication that often is unreported in published case series."
The paper also tells us that implanting electrodes may cause seizures, stating this:
"The primary risk of electrical stimulation mapping is provoking a seizure. This risk may depend significantly on technique; in a review of risks in intraoperative mapping for epilepsy surgery, the risk of seizure was 1.2% with the train-of-5 technique and 9.5% with the 60-Hz technique."
Transcranial Magnetic Stimulation Risks
Transcranial Magnetic Stimulation is a noninvasive technique in which the brain is bombarded by magnetism. The technique is sometimes used in neuroscience research. A wikipedia.org article on the technique states the following:
"Although TMS is generally regarded as safe, risks are increased for therapeutic rTMS compared to single or paired diagnostic TMS. Adverse effects generally increase with higher frequency stimulation. The greatest immediate risk from TMS is fainting, though this is uncommon. Seizures have been reported, but are rare. Other adverse effects include short term discomfort, pain, brief episodes of hypomania, cognitive change, hearing loss, impaired working memory, and the induction of electrical currents in implanted devices such as cardiac pacemakers."
The technique of Transcranial Magnetic Stimulation is a fairly new one, and no one has done has long-term studies on the topic of whether such TMS increases a person's risk of brain cancer, Alzheimer's disease or dementia. If you accept the typical assumptions of neuroscientists about memory, you should tend to suspect that such stimulation might increase a person's risk of dementia. Zapping computers with magnetism is known to incur a severe risk of data loss.
Transcranial Direct Current Stimulation Risks
Transcranial Direct Current Stimulation (tDCS) is a noninvasive technique in which the brain is bombarded by electricity. A scientific paper tells us this:
" Nevertheless, several papers have reported that, in tDCS, some adverse events persist even after stimulation. The persistent events consist of skin lesions similar to burns, which can arise even in healthy subjects, and mania or hypomania in patients with depression. Recently, one paper reported a pediatric patient presenting with seizure after tDCS, although the causal relationship between stimulation and seizure is not clear."
The technique of Transcranial Direct Current Stimulation is a fairly new one, and no one has done long-term studies on the topic of whether such tDCS increases a person's risk of brain cancer, Alzheimer's disease or dementia. If you accept the typical assumptions of neuroscientists about memory, you should tend to suspect that such stimulation might increase a person's risk of dementia. Zapping computers with electricity is known to incur a severe risk of data loss.
The Charade and Farce of "Informed Consent"
Neuroscientists claim that the human subjects used for neuroscience research have given what they call "informed consent." However, there are very strong reasons for believing that a large fraction or most of the subjects in neuroscience experiments do not understand the risks they are taking. Below are some of the reasons:
(1) Unclear "informed consent" documents. A person participating in a neuroscience research study will be asked to sign a document called an Informed Consent document. Such documents are typically long, filled with jargon, and hard for the layman to understand.
(2) "Informed consent" documents failing to candidly discuss all the risks. A person participating in a neuroscience research study will typically be asked to sign a document that is not candid about all the risks involved, a document that fails to adequately inform the person about all the risks involved. The document may give the person false ideas about the risks involved. Some technique such as fMRI scanning may be described as "safe," which gives the impression that there is no risk; but as I discuss above, there are actually very substantial risks involved in fMRI scanning, particularly when it occurs for longer periods, with repeated scans, and higher-intensity scans such as 3T scans and 7T scans. So-called "informed consent" documents are full of "spin" designed to reassure the subject about the safety of the procedures he will be exposed to. Such "spin" often fails to adequately inform the subject of the risks he is taking.
(3) "Informed consent" documents are frequently presented under situations in which the reader is discouraged from taking his time to read the document. Anyone who has gone to a hospital emergency room or a very busy hospital may have experienced a situation under which "informed consent" documents are rather a charade or farce, because of a high degree of time pressure to sign the long documents as quickly as possible. Lengthy fine-print forms are given to someone, with the clear impression given that he is expected to sign them very rapidly, rather than taking minutes to study and properly understand them. For example, a doctor may come to a hospital room and give three pages of fine-print forms for a patient to sign, while impatiently waiting for an immediate signature. I don't know how often such dynamics occur in neuroscience research studies, but I would imagine that the same "hurry up and sign" dynamics frequently occurs.
(4) No one ever verifies that the person reading the "informed consent" document is capable of reading and understanding a document of that type. So-called "informed consent" documents are typically written in college-level language. But studies indicate that roughly half of the US population cannot read well-enough to understand documents written in such language. A very sizable fraction of Americans have a native-language other than English, and a very large fraction of people whose native language is English never learned to read well-enough to understand language written like "informed consent" documents. It would be an easy task to verify that a subject can read and understand an "informed consent" document. You could ask them to read aloud a crucial part of the document, and then to summarize that part in his own words. Scientists never do that.
(5) Rarely does anyone ever verify that a subject spent adequate time reading an "informed consent" document. So-called "informed consent" documents are typically given to people, with some pressure for them to rapidly sign. Almost never does anyone verify that the person spent adequate time studying the document, a very easy thing to do.
(6) Rarely does anyone ever verify that a subject properly understood the risks explained in an "informed consent" document. It would be very easy to verify that someone properly understood the risks explained in an "informed consent" document. You could simply give the person a one-page multiple-choice test, asking him about the contents of the document. Anyone failing to answer all of the answers correctly would be assumed to not understand the risks involved. Such tests are virtually never done.
At the link here, we have a University of Michigan template for an "informed consent" document for a research study. It is ten pages of fine print, written at a reading level that most or a large fraction of Americans will not be able to understand well. The documents mentions an unusually long fMRI scan time of 1 to 3 hours, much longer than the average MRI scan (between 15 and 30 minutes). No mention is made of how strong the fMRI scanner will be (whether it will be 1.5 T, 3T or 7T). The document fails to make any mention of the very real possibility of an increased cancer risk or dementia risk caused by the long scanning, which is small but real and significant in that long a scan. We have a document that will fail to cause most of its readers to understand the risk in the experimentation involved. The document has a profoundly misleading clause claiming "it is anticipated that at least 10,000 subjects will participate," tending to create a reassuring impression of very high numbers of people participating. The truth is that the vast majority of neuroscience experiments involve fewer than 20 human subjects, and a brain-scanning study of more than 50 people almost never occurs.
For all of these reasons and others, the "informed consent" procedures of neuroscience experiments are a charade and a farce. We should assume that the majority of subjects in neuroscience experiments do not understand the risks they are taking. The very idea of a mere "informed consent" is a profoundly defective one. A more stringent standard would have to be followed in order for good morality to be practiced in neuroscience experiments on humans. You might call such a standard the standard of "risk-cognizant consent."
The idea of risk-cognizant consent would be to verify that a subject understood all of the risks involved in an experiment, not merely that he had been informed of such risks in a way that might well have failed to cause a good understanding of the risks. Here is how such a protocol of risk-cognizant consent might work.
(1) Consent documents would be carefully written according to a "plain English" standard.
(2) All risks would be candidly discussed, including known risks, and unknown risks that it might be reasonable to suspect the subject was incurring.
(3) Before any subject was asked to sign such a document, his or her reading skills would be verified (for example, he might be asked to read the first paragraph aloud).
(4) Anyone lacking very good reading skills would be offered the consent document in an audio form or video form, or would have the consent document read to him.
(5) It would be made clear that a test would be given on the content of the consent document, and that therefore it should be studied very carefully.
(6) It would always be verified that the person had spent adequate time studying the written consent document or listening to the audio form of the document, without any of the nonsense going on in emergency rooms, where people are routinely given long documents and pressured to quickly sign them, with medical personnel routinely accepting signatures when people obviously had not taken adequate time to sign what they had written.
(7) All persons signing such a document would then be given a ten-question multiple-choice test trying to determine how well they understood the information in the consent document.
(8) Any persons failing to score very highly on such a test (such as scoring 9 out of 10 or higher) would be excluded from participation in the experimental study.
Following such a protocol would make it likely that the great majority of subjects in neuroscience research understood well the risks they were taking by participating in such research. It is not practical to follow this type of protocol in a rushed hurry-up environment such as a hospital emergency room. But neuroscience experiments never have such a time factor. With neuroscience experiments, there is abundant available time to follow a morally responsible protocol such as the risk-cognizant standard I have described. A mere "informed consent" protocol is not an adequate standard for neuroscience experiments.
Much of today's neuroscience research is morally questionable. The research techniques followed are typically bad, with a very high occurrence of Questionable Research Practices such as way-too-small study group sizes, a lack of a detailed blinding protocol, a lack of pre-registration, and "make it up as go along" analytics following a "keep torturing the data until it confesses" approach. Very often the most dubious and arbitrary computer programming post-processing is occurring, in which scientists senselessly contort the data in any way they please in order to twist the data into some desired form so that a discovery or "statistical significance" can be claimed. There is no benefit to society from such junk research, which causes much suffering and death to animals.
The people who benefit from such neuroscientist busy work are neuroscientists, who get to add to their count of published papers. Serious risks are incurred in such experiments by the human subjects, who are often paid only "chump change" payments such as $20 an hour for the risks they endure. The people lured by such tiny payments are typically some of society's neediest, people in need of every little payment they can earn. Most of the subjects do not understand the risks they are taking, because of the problems like those discussed above. Most neuroscience research these days is of low quality, for reasons such as too-small study group sizes, lack of pre-registration, lack of control groups, and lack of a good blinding protocol. What we have here is mainly activity that is for the benefit of the few (neuroscience professors and their colleagues) at the expense of the many (tax payers who fund the junk research, readers who are misled by misleading claims flowing from the bad research, and research subjects undergoing substantial health risks).
I advise all participants in neuroscience research to keep a permanent record of any document they signed, to collect the names of all participating scientists and the name or identifier of the research study, and to keep a careful record of any health complaints such participants have at any time in the future, whether physical or psychological. Such information may be useful in filing a law suit or claim trying to collect payment for damages inflicted.
Postscript: A paper tells us the following about the newer twice-as- powerful 3T MRI machines that have been replacing the older 1.5T MRI
machines, suggesting their magnetic fields are much stronger than
the strength needed to lift a car:
"The main magnetic field of a 3T system is 60,000 times
the earth's magnet field. The strength of electromagnets
used to pick up cars in junk yards is about the field strength
of MRI systems with field strengths from 1.5-2.0T.
It is strong enough to pull fork-lift tires off of machinery,
pull heavy-duty floor buffers and mop buckets into
the bore of the magnet, pull stretchers across the room
and turn oxygen bottles into flying projectiles reaching
speeds in excess of 40 miles per hour."
According to the paper here ("The effects of repeated brain MRI on chromosomal damage") which
judged genetic damage from 3T MRI scans, "While we do
not report any change after a single MRI session, repeated exposure was associated with an increase in the
frequency of chromosomal deletions." The paper "Genotoxic effects of 3 T magnetic resonance imaging in cultured human lymphocytes" found that chromosomal aberrations (CA) increased in proportion to the length of time someone had a 3T MRI scan. It says, "the frequencies of CAs in lymphocytes exposed for 0, 45, 67, and 89 min were 1.33, 2.33, 3.67, and 4.67 per 200 cells, respectively." Such chromosomal deletions and aberrations probably increase cancer risk, or the risk of equally devastating problems.
At the Courtois NeuroMod site here we have a page detailing frivolous-seeming datasets gathered by what seems like excessive and potentially hazardous brain scanning of subjects. For example, one of the datasets consists of "About ten hours of fMRI data per subject (N=6) while watching the following movies: Bourne Supremacy, The Wolf of Wall Street, Life documentary (twice), Hidden Figures ((twice)." We see nine other datasets that sound just as frivolous, such as one that describes "About ten hours of fMRI data per subject (N=5) while watching the 6th season of the Friends TV show." One of the scientists involved in this project has announced the morally reckless idea of brain-scanning individual subjects for 600 hours. We read this in a paper by him: "The Courtois NeuroMod team will scan six subjects for about 100 hours per year in functional MRI, as well as 20 hours per year in MEG, for a duration of five years, totaling about 600 hours." This is for some medically unnecessary project involving video games.
An October 2024 article published by the US Department of Veteran Affairs is entitled "Metal in MRI contrast agents may cause serious health problems." We learn some shocking details suggesting neuroscience researchers may have been massively endangering their research volunteers:
"New Mexico VA Healthcare System researchers were part of a team of experts who revealed potential chronic health problems linked to magnetic resonance imaging (MRI) contrast agents.
Their review article compiled evidence that the metal gadolinium can remain in the body and lead to multiple conditions, such as kidney injury, debilitating joint and skin problems, and even fatal brain damage....A peculiar, devastating condition, systemic fibrosis, was first identified in 1997 in end-stage renal disease patients. Patients were afflicted with severe pain and a woody or cobblestone-like texture to the skin, as well as joint problems. Nephrologists identified gadolinium as the most significant risk factor in 2006. ...
Now it seems the gadolinium contrast agents have the potential for harm in other patients, not just those with impaired kidney function, based on evidence gathered by Wagner and his team. They said their findings have profound implications for patients experiencing symptoms associated with gadolinium exposure, such as brain fog, skin disorders, joint pain, and permanent disability.
The researchers also discovered gadolinium can stay in the body for a long time, possibly permanently, meaning patients may experience symptoms immediately after as little as one MRI contrast agent exposure or many years after exposure."
The article is discussing the 2024 paper "The safety of magnetic resonance imaging contrast agents," which you can read here. Below are some excerpts:
"Safety concerns with magnetic resonance imaging contrast agents arose when gadolinium was linked to the blight systemic fibrosis, a grievous infirmity (Grobner, 2006).... In addition to severe pain, the skin has been characterized as having a woody induration and cobblestoned. The disease is also associated with severely debilitating joint contractures....Gadolinium-based contrast agents are increasingly associated with cutaneous and systemic abnormalities in patients with normal renal function...Data mining of the United States Food & Drug Administration Adverse Event Reporting System corroborates that skin complications relate to most brands of magnetic resonance imaging contrast agents (Wang et al., 2023). As of 30 September 2023, 31,868 reactions were reported to the United States Food & Drug Administration Adverse Event Reporting System (Figure 2). The leading reaction group for all magnetic resonance imaging contrast agents is skin and subcutaneous tissue disorders (including nephrogenic systemic fibrosis)....Symptoms were skin thickening, 'like hard rubber,' hair loss, skin biopsy with fibrosis, and abnormal calcification on mammograms and x-rays....Acute kidney injury has also been temporally linked to gadolinium-based contrast administration....Neurotoxicity has been linked to magnetic resonance imaging contrast agents in rodent models and case reports (Rogosnitzky and Branch, 2016)....Known complications of gadolinium-based contrast agent administration include kidney damage (Leander et al., 1992; Prince et al., 1996; Sam et al., 2003; Thomsen, 2004; Akgun et al., 2006; Briguori et al., 2006; Ergun et al., 2006; Elmstahl et al., 2007), nephrogenic systemic fibrosis, skin disorders, and sometimes permanent neurologic sequelae (including coma and death). Each dose of gadolinium is fraught with unanticipated risks.. .In humans, a single magnetic resonance imaging contrast agent exposure can trigger nephrogenic systemic fibrosis (Broome et al., 2007; Thomsen et al., 2007; Abraham et al., 2008; Shabana et al., 2008; Leyba and Wagner, 2019). When Dr. Sean Cowper (Professor of Dermatology, Yale School of Medicine) maintained a registry of nephrogenic systemic fibrosis cases, he noted that 46% of cases had just a single exposure....There are many reports of neurotoxicity induced by gadolinium (Table 2). Many case reports detail acute, subacute, and chronic complications (summarized in Supplementary Material). Invariably, these cases required escalation of care for life-threatening scenarios...The doses of magnetic resonance imaging contrast agent needed to induce severe neurologic manifestations (and sometimes death) are minute...Disinherited by the medical establishment, patients spend an eternal time in chronic symptomatic purgatory....Magnetic resonance imaging contrast agents cause kidney injury and gadolinium encephalopathy (sometimes fatal) and may lead to permanent gadolinium retention. Provider education regarding these known adverse events is critical, and informing patients of these risks and outcomes is essential."
Postscript: A year 2024 study ("Evaluation of the Biological Effects of Exposures to Magnetic Resonance Imaging on Single-Strand DNA: An In-vivo Study") found similar results, finding that MRI scanners only half as powerful as 3T scanners can produce genotoxic effects. It reported this:
"The DNA single-strand breaks were significant for all tested parameters in both MRI 1.5 T (p<0.01) and 3.0 T (p<0.001)....The percentage of cells destroyed in the group exposed to 3.0 T MRI was increased to 12.65 ± 1.0 after 10 minutes of exposure."
As shown in its Table 1, the study found that with a 3.0T MRI scanner, the longer you scan, the more DNA damage is done. The reported damage after 40 minutes of 3.0T MRI scanning is given a numerical value of 57, which is nearly twice as high as the damage done after only 10 minutes of scanning (damage given a numerical rating of 32). A similar relation is reported in Table 4, using a different measure of damage. Using that measure, 10 minutes of 3.0T MRI produces DNA damage given a numerical value of 12.66, but 40 minutes of 3.0T MRI produces almost twice-as-bad DNA damage given a numerical value of 22.38. Any DNA damage tends to increase cancer risk.
The 2022 paper here ("The effects of repeated brain MRI on chromosomal damage") reports, "The total number of damaged cells increased by 3.2% (95% CI 1.5–4.8%) per MRI (Fig. 2d–h) (p < 0.001); this increase being higher during the first ten MRI sessions than during the last ten ones (p for interaction = 0.016)."
