The Souls Frail Dwelling House.
Joseph LeDoux's 2002 book ''Synaptic Self'' is a classic.
The book is all about the exact chemistry involved in the synapses between neurons.
The chemistry that makes neurons work, and communicate with each other.
And how that chemistry in the end makes a brain.
See my review of his book: ''The Synaptic Self''.
Stanislas Dehaenes book ''Consciousness and the Brain'' is a really good
book about current attempts
in neuroscience and experimental cognitive science
to understand the brain.
See my review of his book: ''Consciousness and the Brain''.
Jeff Warren takes matters into his own hands in the book ''Head Trip'',
and
investigates the various weird and wonderful states of consciousness,
we might find ourselves in on any given day.
See my review of his book: ''Head Trip''.
Henry Marsh tell us that we live in a very fragile world,
where everything
that we know can all to easily disappear in an instant.
See my review of his book: ''Do No Harm''.
Synaptic Self.
Amazon review (5 stars out of 5)
of Joseph LeDoux book The Synaptic Self.
According to Shakespeare, the brain is the ''The souls frail dwelling house'' (King John. Act 5, Scene 7).
And after reading Joseph LeDouxs 2002 classic, ''The Synaptic Self'', the brain certainly feels frail.
The book is all about the exact chemistry involved in the synapses between neurons.
The chemistry that makes neurons work, and communicate with each other.
And how that chemistry in the end makes a brain.
Certainly, there is a lot of frailty here. Changing the chemical components
of the brain just a tiny little bit, can have huge effects on how we think.
(Obviously) The book does not give us all the answers about how the brain works. But the book is an excellent primer on synapses in the brain, and how this could eventually
lead to something as amazing as a human mind.
Indeed, the story about synapses in the brain is wildly fascinating.
And the book contains both an overview on how synapses actually
works, how the chemistry involved might be changed, and with what results.
It all starts off with memory. We are our memories. Where memories are intimately
connected to what goes on in synapses in the brain.
Changes in these synapses could perhaps improve memory by
altering the molecular basis of synaptic plasticity.
Ultimately, it might be possible to find a drug that speeds up learning.
And it is not just speculation. There has been some success, rats given the compound ampakine seems to be learning faster.
Perhaps because this drug increase the efficiency in synapses, and thereby
facilitate LTP (long-term potentiation) induction.
And ampakine isn't the only chemical at work in the brain.
Other chemicals are at work in connection with stress. LeDoux offers
a very illustrative description of what might be going on (A pretty scary story actually).
During stressful conditions, the concentrations
of cortisol rises in the bloodstream.
It travels through the bloodstream to the brain, where it binds to receptors in the hippocampus.
Here, it disrupts normal activity and weakens the ability to form memories.
Indeed, stressed rats do porly in tasks that require the hippocampus,
such as spatiel learning.
If the stress continues, hippocampal cells begin
to degenerate and die. Depression might follow.
Not surprising, stress hormones also have an adverse impact on the prefrontal cortex,
and may contribute to why people make bad decisions
under stress.
The stress is often caused by exposure to fears and anxieties (for an extended period of time).
If this allows the amygdala to run the show unchecked,
fear takes root in working memory, which will
then further alter the processing of other areas.
Eventually, everything becomes biased by the emotion that has
made camp in working memory. Not good...
But excellently explained in LeDoux's book.
And this isn't even the worst way to change chemical balances
in the brain. Balances that are so important in keeping us sane.
When people take LSD they can have powerful hallucinations.
Furniture in a room can assume grotesque, threatening forms,
people can turn into strange unknown creatures.
So, if LSD produces these psychotic states
by altering neurotransmission in the brain,
sanity might require a certain right level of these neurotransmitters!
It follows that changing these transmitter levels might be a way of treating
many mental ilnesses.
Many books about the brain focuses solely on cognition.
How the brain ''calculates'' things.
Forgetting emotion and motivation. Which is a bit troubling if it should be considered
a study of the whole mind.
I.e. you might be able to play chess without emotion and motivations. Indeed, perhaps, you play even better, if you are not distracted by emotions like love, anger
or fear.
But feelings and strivings must be included in order to understand
the whole human mind.
Behaviour that is guided by things like compassion,
or guilt over actions not taken - can only be understood in the light of emotion and motivation.
Very satisfying, LeDouxs book treats emotion and motivation just as seriously as cognition.
Even though he is very upfront with the fact that much is still
unknown, when it comes to emotion and motivation in the brain.
The book also has some interesting sections about seeing the human mind
from different levels, viewpoints.
I.e. some people don't like to be told that they might exist at other levels
than the level of conscious awareness.
Reductionism to the level of synapses does come down well everywhere...
And LeDoux acknowledges that it is a problem in reductionism that it can lead you to describe phenomenon at the wrong levels.
E.g. describing a
poem at the level of the atoms that make up the book the poem is printed in,
doesn't make much sense. Phenomenons needs to be described at the right level.
Here, LeDoux has some important observations about how different
points of view can support each other, and enrich each other, without necessarily
invalidating each other.
A great read.
Posted on Amazon, January 14th 2015.
Amazon: [1].
-Simon
Simon Laub (Let me Google that for you).
www.simonlaub.net
Understanding Consciousness and the Brain.
Amazon review (5 stars out of 5)
of Stanislas Dehaenes book Consciousness and the Brain.
Stanislas Dehaenes book ''Consciousness and the Brain'' is a really good
book about current attempts in neuroscience and experimental cognitive science
to understand consciousness and the brain.
The brain is obviously an astonishingly complicated and intensely intricate
thing, filled with billions of spiking neurons talking to one another,
evolved over millions of years. So, it is no surprise that it is
difficult to understand. Indeed, perhaps it is more surprising that
it is not totally incomprehensible...
Dehaenes book adds to the feeling that we can actually
understand some parts of what might be going on - Which is
a quite an achievement. The book has a good balance between
overview and details, between giving us an understanding of what might
be be going on in the brain, without drowning us in details about the brains microcircuits.
Take visual perception.
Dehaene introduces us to some
of the problems that our visual system has to deal with.
Our retina is full of imperfections.
- There are blood vessels
running in front of the photoreceptors.
As we do not see this, it follows that our brains ''cleans it up''.
And luckily so, it would not be good to look at the world and constantly be distracted
by bloody curves.
- In the retina the input is blown up toward the center.
Yet, we don't have a tunnel like experience of the world.
It follows that the brain corrects this.
- Outside the center of our gaze, the retina contains
very few color sensitive cones. But we are not color blind outside the center
of our gaze. We do not walk around in a black and white world that suddenly
becomes technicolor at the center of our attention.
Again, in order to give us a full technicolor world,
the brain is doing a lot of behind the scenes processing
that pieces together a world in color.
- In the "blind spot" in our retina, at the place where
the visual nerve goes into the brain, the retina is without light receptors.
No problem, the brain fills in with tectures that look like
what is around the blind spot.
- Our world is not shaky, eye and head movements
has been corrected, and the scene has been reinterpreted
based on knowledge about similar scenes.
And all of this is done unconsciously before anything is
presented to the conscious self.
Wow.
And (it is all) brilliantly presented in Dehaenes book.
The ancient greeks asked us to know ourselves.
But Dehaene cleverly notices that we can
never know ourselves completely. All of the
unconscious processes - most of what we are - will forever
remain hidden! And with these processing mechanisms
hidden, we will never be able to predict how we
will behave outside our comfort zone of past experiences.
Dehaene ties it all together with Bernard Baars's ''global workspace'' theory of consciousness.
In this model, what we experience as consciousness is the global sharing of information.
There might be millions of mental representations
floating around in the brains unconscious regions, but one can be selected
because it is relevant for the present goals.
And, in consciousness this representation can be made available to other systems in the brain.
(More detailed) In Dehaenes words, what we perceive in consciousness may be likened to
the sculpting of a statue. Starting with a raw block of marble,
and chipping away most of it, an artist progressively exposes his vision.
Inside the brain we have hundreds of millions of workspace neurons,
just firing away at their baseline rate. We then perceive the world
by silencing most of them, keeping only a small fraction
active. This active set of neurons then give us the contours
of conscious thought.
In the book, Dehaene is careful to back his ideas up with experimental data.
This also happens here. The silencing of neurons can
actually be measured in form of the P3 wave associated with conscious thought.
I.e. during conscious perception, only a few neurons are active,
while the rest are silenced. The neurons who codes features that
are irrelevant get a signal to stay quiet! And because many
more neurons are inhibited than are activated, all of these
voltages end up forming a large wave on the head - the P3
wave that can be detected when consciousness occurs.
A wave that indicates what the thought is not about!
It is some other voltages that indicate exactly what the
thought is about, lasting as long as we keep the
objects in our minds. And collapse when the objects goes out
of the mind.
It is an absolutely awesome book, I only have
one tiny little problem with it, which is
strongly related to how neuroscience operates under the ontological assumption of physicalism, according to which only the fundamental phenomena studied by (current) physics exist.
This assumption might very well be true, but reading in the book
you get the impression that the hard problem of consciousness
will be solved (soon?) within this framework.
I.e. the hard problem
of going from electrical signals to actually sensing (subjectively)
sounds, feelings etc. is glossed over a little too quickly imho.
Finding neurons that correlate with the contents of consciousness
might indeed be a first step. But what the next steps will be (on the roads towards explaining consciousness) is still
unknown. As are the theories that will get us there. It is not just smooth sailing from here. It could have been stated more explicitly in
the book.
Still, I wont deduct any stars because of that.
It is still a great read.
Posted on Amazon, January 21st 2015.
Amazon: [2].
-Simon
Simon Laub (Let me Google that for you).
www.simonlaub.net
Head Trip.
Amazon review (5 stars out of 5)
of Jeff Warrens book Head Trip.
The mind remains mysterious.
As a matter of fact, the more we learn about it, the more mysterious it becomes.
Starting with something as simple as sleeping, Jeff Warren let us
know that the way we sleep today (in the western world) was
not how we used to sleep, back in earlier times (without electricity)
when winter nights were a 14 hours drawn out affair - with nothing
to do but sleep.
It was a different world back then, in the dark.
With other thoughts, and other dreams.
Indeed, sleeping in many cultures is still
nothing like the western way of sleeping.
Here, it is still very much a social activity. Where people sleep together
in big multigenerational rooms with all sorts of things
going on during the night - procreation, chatting, information
exchange. Throw in some poultry, and it becomes a place where
people feel safe and secure...
Someone will always be watching, and making sure that everyone is safe.
Being awake is also many things.
Indeed, in Jeff Warrens account we are introduced to eastern meditative practices that
seem to have reached outposts of consciousness far beyond the grasp of western science.
Some of these states are described in the buddhist text Visuddhimagga (English: The Path of Purification). A book that introduces us to states of consciousness very different
from the states we usually find ourselves in.
Not surprisingly, it takes years of practice to work your way up these
jhana states. And things do become more and more esoteric the higher we go in the jhanas.
Indeed, very few meditators claim to have reached the top.
But with Jeff Warren we get a sniff of it all.
A great book, and very entertaining.
Posted on Amazon, February 19th 2015.
Amazon: [3].
-Simon
Simon Laub (Let me Google that for you).
www.simonlaub.net
Compassion in a Heartless World
Amazon review (5 stars out of 5)
of Henry Marshs book Do No Harm. Stories of Life, Death, and Brain Surgery.
You might wonder why people would ever want to read about a long list of shattering
tragedies caused by horrible brain diseases and trauma?
Well, the books long list of horrors might be just the thing we need to
remind us that life is a precious gift!?
And Henry March is certainly a good guide in these strange lands.
It might all be pretty gruesome, but there is still compassion.
There are people who cares, and who spend their lives
trying to heal others. There are even people out there who care so much
that they suffer when their patients suffer. Indeed, you can see
it in Hery Marsh's face that a life as a neurosurgeon
has not left him untouched.
So, it might be horrible world out there, a world filled
with tragedies, but there is still hope, and there is still
compassion. So, it isn't all bad...
Clearly a message that deserves 5 stars.
And it obviously doesn't hurt the book that it is well written,
filled with many good insights and comments about the
world we live in.
Posted on Amazon, May 27th 2016.
Amazon: [4].
-Simon
Simon Laub (Let me Google that for you).
www.simonlaub.net
