A
scientific paper reached the following conclusions, indicating a huge
hype and exaggeration crisis both among the authors of scientific
papers and the media that reports on such papers:
Thirty-four
percent of academic studies and 48% of media articles used language
that reviewers considered too strong for their strength of causal
inference....Fifty-eight percent of media articles were found to have
inaccurately reported the question, results, intervention, or
population of the academic study.
At
this link you can find analysis of recent misleading press releases
on health research, many of them issued by major organizations such
as universities and hospitals. Here are some of the article titles
from the past several months, each corresponding to a faulty
scientific press release:
- Claim that milk protein alleviates chemotherapy side effects based on study of just 12 people
- University PR misleads with claim that preliminary blood test detects early pancreatic cancer
- Supposed ‘breakthrough’ for detecting gut disorders tested in only 12 healthy people
- Announcement oversells blood test for predicting treatment outcomes in prostate cancer
- No,
an asthma drug tested in mice does not bring 'new hope' to
Alzheimer's patients, at least not yet
- University touts new device to protect women from HIV, buries fact it was only tested in rabbits
- ‘Daily ibuprofen can prevent Alzheimer’s disease’ and other unproven claims by Canadian neuroscientist
But
in none of these cases do we have a press release as faulty as a
particular press release issued by Johns Hopkins University, a press
release that very much misled the reader about an important
scientific study. The study was one led by Richard Huganir to look
for long-lived proteins in synapses. There is a reason why such a
study was of considerable philosophical interest.
The most popular scientific doctrine concerning how memory is stored is the doctrine that memory is stored by a process of the strengthening of synapses of brains. But what we know about the lifetimes of proteins in synapses contradicts this doctrine. Humans can remember old memories for as long as 50 years. But as far as we know, the proteins in synapses have average lifetimes no longer than a few weeks. How could memories be stored in synapses that have their parts being constantly replaced? That would be like storing an essay written on leaves on a table, when the wind is frequently blowing away the leaves, and replacing them with other falling leaves -- not something suitable for long-term information storage.
The Huganir study was one specifically looking for long-lived proteins in synapses. If lots of long-lived proteins could be found in synapses, with lifetimes of many years, then it might be that the main theory of a brain storage of memories (the synapse memory doctrine) is not so unbelievable as it once seemed. But if few or no brain proteins were found with very long lifetimes, it would bolster the case that brains are not up to the job of storing human memories that can last for 50 years.
Now, judging from the press release about this study that was released by Johns Hopkins University, you would think that the study was a great success. The press release was entitled “In Mice, Long-Lasting Brain Proteins Offer Clues to How Memories Last a Lifetime.” Talking about two proteins in the body that last for years (crystallin in eyes and collagen in connective tissue), the press release states the following, ending with a quote from Richard Huganir, the leader of the study:
His team also knew of long-lasting proteins such as crystallin, which makes up the lens of the eye, and collagen, found in connective tissue. Proteins within nuclear pores, the transport tunnels in and out of a cell’s nucleus, and histones, a kind of “spool” that DNA winds around, also are very stable. “So, we reasoned, there must be proteins in those synapses that are long-lasting, too, and we believe we have found a lot of them.”
The problem is that this statement does not at all match what is in the actual scientific paper, which found no such thing. Quite to the contrary, the paper found the following:
- Studying thousands of
brain proteins, the study found that virtually all proteins in
brains are very short-lived, with half-lives of less than a
week.
- Table 2 of the paper
gives specific half-life estimates for the most long-lasting brain
proteins, and in this table only 10 out of thousands of brain
proteins had half-lives of 10 days or longer.
- Of the proteins whose
half-life is estimated in Table 2, only one of them has a half-life
of longer than 30 days, that protein having a half-life of only 32
days.
- A graph in the paper
indicates that none of the synapse proteins had a half-life of more
than 35 days.
Below is a graph from the Huganir paper. It shows that the study found that virtually all proteins in synapses are very short-lived.
Below is another graph from the same paper. It shows that the study found that virtually all proteins in synapses are very short-lived.
Judging from these graphs, none of the proteins found had a half-life of longer than 35 days, and only a few had a half-life of more than 14 days.
Given these results, it is extremely misleading for Huganir to be saying in the press release that he found “a lot” of “long-lasting” proteins in synapses. He found no such thing, and did not even find a single protein with an average lifetime of years.
So far from offering “clues to how memories last a lifetime,” as the misleading Johns Hopkins press release states, this study gives us all the more reason for thinking that memories would not even last a year if they were stored in our synapses as our neuroscientists maintain. An accurate title for the press release would have been “Study Indicates Synapses Cannot Store Memories for Longer Than a Month.”
The results in the Huganir paper are consistent with the results from this 2018 paper by German scientists that studied a similar topic. The paper starts out by noting that one earlier 2010 study found that the average half-life of brain proteins was about 9 days, and that a 2013 study found that the average half-life of brain proteins was about 5 days. The study then notes in Figure 3 that the average half-life of a synapse protein is only about 5 days, and that all of the main types of brain proteins (such as those in the nucleus, mitochondrion, etc.) have half-lives of less than 20 days. The 2018 study here precisely measured the lifetimes of more than 3000 brain proteins from all over the brain, and found not a single one with a lifetime of more than 75 days (figure 2 shows the average protein lifetime was only 11 days).
In this paper by German scientists, tubulin proteins are the only type of brain proteins identified as having a half-life of longer than 14 days. Tubulin proteins are used in tube-shaped microtubules. But there's no chance that such microtubules could be a stable storage site for memory, because microtubules are known to be very short-lived. A scientific paper tells us how short-lived these microtubules are:
Neurons
possess more stable microtubules compared to other cell types (Okabe
and Hirokawa, 1988; Seitz-Tutter et al., 1988; Stepanova et al.,
2003). These stable microtubules have half-lives of several hours and
co-exist with dynamic microtubules with half-lives of several minutes.
In this case of the Hopkins press release, personnel at a university are to blame for bad science reporting. That is very often how it is. An article entitled, “How Scientists Contribute to Bad Science Reporting” refers to a study that found that about one third of science press releases contain exaggerated causal claims. The article states the following:
But a recent study suggests that journalists aren't the weakest link. The source of misrepresentations and exaggerations in science news stories is often much closer to the scientists themselves: press releases put out by researchers' own institutions. Surveying hundreds of news stories and press releases about medical research, a group of scientists at Cardiff University found that most exaggerations and misrepresentations of science in print news "did not occur de novo in the media but was already present in the text of the press releases produced by academics and their establishments." …. When a press release had no exaggerations or misleading claims, relatively few—less than 20 percent—of the related news stories carried misleading claims. But when a press release did include an exaggerated or misleading claim, the majority of the associated news stories also featured exaggerations and misleading claims....More than a third of the press releases examined contained misleading statements or exaggerations, so the bad influence of academic institutions on science reporting is very likely substantial.
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