The
leading 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 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.
This paper finds that synaptic proteins turnover at a rate of about 17% per day. This paper says that a study of 90 synaptic proteins found an average lifetime of only about 12 days, with the most long-lived one lasting only 48 days.
This paper finds that synaptic proteins turnover at a rate of about 17% per day. This paper says that a study of 90 synaptic proteins found an average lifetime of only about 12 days, with the most long-lived one lasting only 48 days.
Such
a fact is extremely troubling to those who think that long-term memory is
stored in your brain. So what do you when there is a troubling fact
that contradicts your theory of memory? You ask the government for
lots of money to look for something that might help out your bad
theory, even though that there is no evidence that the thing you are
looking for exists.
That
seems to be what is going on in the case of National Institute of
Health Project # 1R01MH112152-01A1, described here. Some $610,745 has been
granted to Richard L. Huganir of Johns Hopkins, so that he can look
for “exceptionally long-lived proteins” in synapses. Given what
we know about the extremely short lifetimes of synapse proteins, this
seems to be like getting lots of money from the government to look
for flying rats.
Below
is an excerpt from the grant proposal:
Most
of the individual proteins that are known to make up the synapse will
turnover, being degraded and replaced within hours to a few days.
Therefore the question remains as to what physical substrates
underlie the persistence of long-lasting memories. One possibility is
that exceptionally long-lived proteins (LLPs) reside in synapses and
act as molecular anchors to maintain the synaptic strength or a
network property that defines a given memory.
The grant proposal
admits that there is no evidence that any such “exceptionally
long-lived proteins” exist in synapses, for it says, “no studies
to date have addressed whether such proteins exist at synapses and
contribute to the establishment and maintenance of long-term
memories.”
Given
the known extremely short lifetimes of synaptic proteins, we should
characterize this research project as a wild goose chase. It seems to
be kind of a desperate shot-in-the dark to try to save the
materialistic paradigm's claims about memory. No doubt our neuroscientists are
troubled by the idea that because of synapse proteins with very short
lifetimes, the brain is simply not up to the job of storing memories
for years. That would seem to mean we could only explain human 50-year
memories by supposing that our minds must involve something more than
the brain, such as a soul or some mysterious immaterial consciousness
infrastructure.
There
is no reason to think that Huganir will find any synapse protein that
can last for years. Let's suppose you were to make the very
surprising discovery that some protein in synapses lasts for years.
We would still know that almost all the proteins in synapses are very
short-lived. So the discovery of such a long-lived synapse protein
would be futile. It would be like trying to explain the persistence
of a much-used book supposedly lasting 50 years – a book made almost entirely
of gossamer spider-web pages – by finding that every twentieth page
is not made of flimsy short-lived gossamer but of paper. That doesn't
do you much good in explaining how most of the book's information
could persist for 50 years.
I
may note an irony here. Human observers have got much evidence for
astonishing things that cannot be explained by modern science: things
such as extrasensory perception, apparition sightings, mysterious orbs with highly repeating stripe patterns, and near-death experiences. Such things challenge the dogmas of the materialistic paradigm. If you were to ask
for a half million dollars for a government grant to investigate
further such things which have already been extensively observed, you
would be turned down quickly, and you would be told: not one cent for such research. But if you seem to be in service of
prevailing dogmas, you will have no problem getting a half million
dollar grant to go on a quixotic quest looking for something that has
never been observed, which is what Huganir has got. I guess the rule
is: there's no government research money for anything that might
challenge the materialistic paradigm, but plenty of government research
money for any project that might help patch one of the many holes
that have sprung up in such a paradigm, which are threatening to sink
the paradigm.
The government seems to have been very generous in giving lots of grants to Huganir, who we can assume is mainly involved with projects with a larger chance of success than this one.
Postscript: The latest and greatest research on the lifetime of synapse proteins is the June 2018 paper “Local and global influences on protein turnover in neurons and glia.” 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 nucleus, mitochondrion, etc.) have half-lives of less than 15 days.
See this post to see Huganir's results. He got the result I predicted, basically the same result as the June 2018 discussed above. He found that virtually all synapse proteins are very short-lived, and the paper gives no clear evidence of any synapse proteins that last for years. But the press release announcing the study announced the exact opposite of what the data found, in an outrageous case of the "press release doesn't match the scientific paper" phenomenon that is shockingly common in modern academia.
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