
The new enthusiasm for neuroplasticity - t23
http://www.bbc.com/future/story/20151123-the-brains-miracle-superpowers-of-self-improvement
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CuriouslyC
Research has already demonstrated that adult neurogenesis occurs in specific
areas of the brain. I wouldn't be surprised if neurogenesis occurs throughout
the whole brain, in response to proper stimulus. I suspect that the reason it
doesn't generally occur is that it is more efficient to grow new synapses
between existing neurons than to differentiate stem cells into new neurons.

By analogy, muscles can undergo a fairly good amount of hypertrophy just via
protein synthesis of contractile elements. However, in response to severe
stress/trauma, satellite cells (a form of quiescent, partially differentiated
stem cell) merge with muscle cells; the result of this is a muscle cell with a
greater potential for hypertrophy.

Perhaps neurogenesis and only occurs under special conditions (like muscular
myonuclear addition), such as extremely novel stimulus, or great mental
effort. This would make it extremely difficult to induce experimentally.

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eldude
Overall, an excellent and very balanced article, especially the care taken to
address what neuroplasticity really means, and what it doesn't, as well as the
current state of research.

The conflation of "personal-transformation" as a "myth" with the myths
associated with neuroplasticity is unfortunate though:

> [Chris McManus, Professor of Psychology and Medical Education at University
> College London] believes it is just the latest version of the personal-
> transformation myth that’s been haunting the culture of the West for
> generations.

&

> This myth – that we can be whoever we want to be, and achieve our dreams, as
> long as we have sufficient self-belief – emerges again and again, in our
> novels, films and news, and TV singing competitions featuring Simon Cowell,
> as well as unexpected crazes like that for neuroplasticity.

"Haunting"? Possibly, the author has some derision considering his "great-
great-uncle" is "the inventor of the ’self-help’ movement". Regardless, it
felt like a rather unscientific ax to grind.

FWIW, the author points out that neuroplasticity myths are used to justify
some undesirable conclusions, though he stops short of providing examples or
references.

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meow_mix
Kind of sad to see the author take such a derogatory outlook on some of these
self-help approaches. These sorts of things do appear periodically but they do
not promise neuroplasticity as a quick cure-all as the author says they do.
What's great about thinking of neuroplasticity as a sort of self-help is that
it by definition takes a great deal of work to "rewire" any part of the brain.
Neuroplasticity is the promise of improvement using hard work, so I suppose
I'm upset with the authors standpoint.

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pwm
It amazes me how much we already discovered about our brains, yet how little
do we really know about it and how much more is to know. From a CS point of
view it is also very exciting how current hot areas, like machine learning are
closing on on the same questions from a different angle. Are we digital or
analog? Is our self simply a reflection of an incredibly deep, recursive,
emergent meta-structure or is there some ineffable underlying level? Or both
or neither? :) Exciting times we live in...

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nonbel
>"For many years, the consensus was that the human brain couldn’t generate new
cells once it reached adulthood. Once you were grown, you entered a state of
neural decline. This was a view perhaps most famously expressed by the so-
called founder of modern neuroscience Santiago Ramon y Cajal. After an early
interest in plasticity, he became sceptical, writing in 1928, “In adult
centres the nerve paths are something fixed, ended, immutable. Everything may
die, nothing may be regenerated. It is for the science of the future to
change, if possible, this harsh decree.” Cajal’s gloomy prognosis was to
rumble through the 20th Century."

Can anyone point out what evidence is cited that conflicts with Cajal's claim?
I don't see it. They mention functional reorganization (a change in the
weights between neuronal connections as opposed to structure), but don't
address why this is an inadequate explanation:

"Neuroplasticity can refer to structural changes, such as when neurons are
created or die off or when synaptic connections are created, strengthened or
pruned. It can also refer to functional reorganisations, such as those
experienced by the blind patients of Paul Bach-y-Rita, whose contraptions
triggered their brains to start using their visual cortices."

~~~
lobo_tuerto
Do you mean something like this (from the article)?

"Three years later, a Swedish-American team, led by Peter Eriksson of
Sahlgrenska University Hospital, published a study in Nature that showed, for
the very first time, that neurogenesis – the creation of new brain cells – was
possible in adults. In 2006, a team led by Eleanor Maguire at the Institute of
Neurology at University College London found that the city’s taxi drivers have
more grey matter in one hippocampal area than bus drivers, due to their
incredible spatial knowledge of London’s maze of streets."

~~~
nonbel
Also, as of at least 2013, people were still publishing papers skeptical that
neurogenesis is being measured here:

>"In the adult cortex, one point of consensus is that the numbers of adult-
born neurons are low and their lives are short. Thus, we need to search for
them, like needles in a haystack, perhaps in many “haystacks” subject to
different conditions. In addition, supplemental approaches need to be
developed since BrdU may label neurons repairing their DNA; alternatively,
markers of DNA repair need to be routinely performed. Due to their low number,
it is difficult to conclude whether the identified BrdU/NeuN+ cells are the
result of progenitor proliferation or neuronal repair."

[http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3534801/](http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3534801/)

