Thanks toNew Scientistfor bringing our attention to this
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These are the clearest pictures ever taken of what is the starting point of every human life: ovulation occurring inside a woman's body
... [was] removed from their moms and placed in an incubator as a group for a few hours a day for several days.
.. lack of touch triggers an inappropriate activation of the stress system. Scientists found that merely stroking the infant rodents with a tiny brush could prevent many of the effects of the long separation.
- Tip of the Hat to Brain Briefings.
A fun little article about memory from the The Boston Globe about how we think about remembering. The general consensus used to be that there was an index part of the brain that kept track of everything's whereabouts in memory. Turns out, not so much. Ever had that experience when you..just...can't...quite... remember?
Here's the key passage -
The tip-of-the-tongue experience, however, is leading researchers to question this straightforward model. According to this new theory, the brain doesn't have firsthand access to its own memories. Instead, it makes guesses based upon the other information that it can recall. For instance, if we can remember the first letter of someone's name, then the conscious brain assumes that we must also know his or her name, even if we can't recall it right away. This helps explain why people are much more likely to experience a tip-of-the-tongue state when they can recall more information about the word or name they can't actually remember.
The JASONS are a semi-secret research arm of the Defense Department. They issue occasional papers about areas of interest, and when they do, Secrecy News from the Federation of Atomic Scientists is usually nice enough to let us know.
This latest report is at the intersection of neuroscience and war, the subject of a new blog I am writing called The Brain at War. A natural outgrowth of my interest in brain development and function has been an increasing interest in brain damage and dysfunction, especially dysfunction caused by injury in war. For more on Traumatic Brain Injury, PTSD and "normal" brain response to war check it out. We'll be looking at cutting edge imaging and diagnostic tools, developments in brain-mind theories and rehabilitation research. This is our project -
When you break your arm, you know what it means to say you're healed: you can do what you did before the injury. What does it mean to heal from a brain trauma?
[T]he present state of the art in pharmaceutical intervention in cognition and in brain-computer interfaces, and considered how possible future developments might proceed and be used by adversaries.”
“The most immediate human performance factor in military effectiveness is degradation of performance under stressful conditions, particularly sleep deprivation.”
“If an opposing force had a significant sleep advantage, this would pose a serious threat.”
In Jewish religious law, as laid out in Leviticus, there are times when a woman must separate herself from the community. There are also times when a man must do the same. Traditional commentary has referred to the state the necessitates removal as tamei, which was translated into English as impure. The call for separation was understood to be a demand, made by the community of the individual. Tahor, by contrast, was translated as pure, and was the necessary state to join in daily life with the rest of the community
There are several ways to become impure and they range from gossiping, contact with a dead body, menstruation and even giving birth. During the time of the first and second temple in Jerusalem, the journey from tamei to tahor was accomplished by a combination of ritual and actual cleansing. 
Most commentary on tamei and tahor has either been a legal style analysis of when one state or the other has been achieved or a humble query into what these causes of "impurity" could possibly have in common. Can you see the common thread that would have a community temporarily exile someone who is menstruating or came in contact with a dead body or recently gave birth?
Neither could I. So, what does this have to do with the gender-unspecified proto-human?
Some Jewish commentators have suggested a new way to understand tahor and tamei that transforms the dichotomy from pure/impure to ways that we connect with other people and god.
I learned this from Rabbi Michael Lerner of Beyt Tikkun. In his telling, tamei is not a separation enforced from without, it is the state of connecting to the transcendent and holy on your own. And Tahor is not purity, but connecting as part of a community.
The law in other, more secular, words lays out moments, birth and death usually, when our connection is primarily to the mystery within. How we can transition back to connections in our community is no simple task, and because the section lays out clearly how to go from solitude to community, I divine an assumption on the part of the author of this chapter that it takes effort to connect with others. That we need time and space away from community to be whole.
Rabbi Lerner takes it a different direction, one that doesn't gloss over the inclusion of gossip as a source of tamei as I do. Lerner's belief is that gossip, birth and death all disrupt communities, and the rituals laid out in Leviticus are about mending the rift.
Those first few months after the birth, I've heard them called the Fourth Trimester, have always been described to me as a trying and cloistered time. When I visited my friends and their shiny new son Noah, it was 48 hours lived in an unending twilight of drawn curtains and quiet conversations.
This child of ours will need guidance and nurturing to become fully who they are. What rituals do we have in place these days for the parents to make their own re-appearance in their community? To make their journey from drawn curtains to bright light?
- This is the aforementioned Noah
I wrote about my ignorance of human memory in a previous post.
I need to dig out the inapt metaphors I have growing in my mental garden. I am starting with the kudzu of conceits, the mental weed that has spread widest: human memory is / is not analogous to computer memory.
In my ignorance, I have easily shuttled back and forth between the positive and negative formations of the metaphor. As I read more deeply on the subject I was tethered to the informing metaphor, and limited by it.
Today I seek freedom. My first step was the trusty folks at Science Blogs, a friendly lily pad floating out in the internet pond.
My first stop was this post at Developing Intelligence, titled 10 Important Differences Between Brains and Computers. The four differences I highlight below are just the hoe to do the job:
[T]he idea that computers require memory has lead some to seek for the "memory area," when in fact these distinctions are far more messy. One consequence of this over-simplification is that we are only now learning that "memory" regions (such as the hippocampus) are also important for imagination, the representation of novel goals, spatial navigation, and other diverse functions.
[Human] short-term memory seems to hold only "pointers" to long term memory whereas RAM holds data that is isomorphic to that being held on the hard disk.
the mind emerges directly from the brain, and changes in the mind are always accompanied by changes in the brain. Any abstract information processing account of cognition will always need to specify how neuronal architecture can implement those processes
despite your intuitive feeling that you could close your eyes and know the locations of objects around you, a series of experiments in the field of change blindness has shown that our visual memories are actually quite sparse. In this case, the brain is "offloading" its memory requirements to the environment in which it exists: why bother remembering the location of objects when a quick glance will suffice?
One last word before I never write about penis thieves again. In the previous post, I wrote about the ir/resistible impulse to surrender to mob thinking.
What baffles me are the "victims", Reuters interviewed Kinshasa's police chief, Jean-Dieudonne Oleko.
But when you try to tell the victims that their penises are still there, they tell you that it's become tiny or that they've become impotent. To that I tell them, 'How do you know if you haven't gone home and tried it'
In the first 16-21 days the neural tube closes.
That, my friend, is what you looked like at one point. 
That groove right down the middle was what your proto-spinal cord looked like. And that glowing knob on the right? That'd be your brain.
There is also a disturbing resemblance to a fluke worm.
That is pretty gross wondrous.
It has been over a year since Seung-Hui Cho murdered his community, plowed salt into his soil and then snuffed himself out.
Unrooted.
His sister had deep connections in rich soil. She had friends who nourished her, a bright future to shower sunlight on her leaves and, just as important, it was bright enough to coax greater growth towards the light. Her roots were strong enough and deep enough to support her when foul weather challenged her integrity.
Roots, sunlight and rich soil.
But her brother never found fruitful purchase. The light where he grew was too dim to increase growth to the light. Two seeds, sown in nearly the same soil, nurtured in the same backyards by the same gardeners, and one flourishes and the other stunted, grew first diseased and then poisonous.
It could be malformation. A genetic anomaly. Or bad luck. Maybe the gardeners were more attentive to the health of the one sapling and poor stewards to the other.
What kind of gardener will I be?
I am starting here by posting a call for Airplane Behavior from you. I've not done this before, so you can be sure I am serious. No inappropriate laughter and no tantrums. When we fly on an airplane, we act like big boys and girls. Period.
For those who don't know, when a parent demands airplane behavior it is Defcon 1: the this-is-not-a-drill moment for childhood restraint.
The parent cannot cry wolf with this. And the child must know that sitting still is the scheduled activity for today. Temper tantrums, attacks of shpilkes and repeated importuning will bring Old Testament style punishment as surely as the tide will rise. No appeals to angels will be honored. Sorry.
When I was a Peace Corps volunteer in Senegal there was a rash of vigilante murders. Mobs roughing up thieves was not frequent, but it was also not unusual. Deadly beatings were extremely rare. So the murders were notewothy, as was the accused crime: penis theft. (Airplane behavior!)
Looks like it isn't unique to. From an article in Reuters, -
Rumors of penis theft began circulating last week in Kinshasa, Democratic Republic of Congo's sprawling capital of some 8 million inhabitants. They quickly dominated radio call-in shows, with listeners advised to beware of fellow passengers in communal taxis wearing gold rings.
Purported victims, 14 of whom were also detained by police, claimed that sorcerers simply touched them to make their genitals shrink or disappear, in what some residents said was an attempt to extort cash with the promise of a cure.
Not sure what got me thinking about this. I heard a story. On a playground in elementary school. After Mr Pletcher's history class in high school. Who knows.
The story was that consciousness doesn't stop until oxygen runs out to the brain and just because you cut off NEW blood flow to the brain, the lights don't go out immediately.
So goes the story, Louis XVI was able to stare at his own body as his head rolled slowly away.
For how long though and young me cried out inside. A default mode of brain function -- Raichle et al. 98 (2): 676 -- Proceedings of the National Academy of Sciences -
This dependence of the brain on oxygen is highlighted by the fact that failure of oxygen delivery to the brain, usually the result of a stoppage of the heart, results in unconsciousness within seconds.
But if you want to, here you go:
Critical Periods of Vulnerability for the Developing Nervous System: Evidence from Humans and Animal Models
Why did we develop intelligence at all? If it was so great, in oither words, why isn't everyone else doing it? This is from an article in the Literary Review of Canada Online about a new book called - Darwin on My Mind -
The author starts us off with a significant point, namely that most organisms do not think. Most organisms certainly are not rational. Yet they do all right.
Moreover, rationality is not necessarily a key to success. Well thought-through courses of action can go wrong; daft decisions can lead to success.
[We] might.. compound the paradox a bit by pointing out that thinking is expensive. It requires big brains and they in turn demand lots of protein...
As the late evolutionary paleontologist Jack Sepkoski used to say: “I see intelligence as just one of a variety of adaptations among tetrapods for survival. Running fast in a herd while being as dumb as shit, I think, is a very good adaptation for survival.”
Once you get started looking at how things normally develop, you find eye popping examples of not normal. Most are horrifying. Nightmare inducing.
Williams Syndrome is different.
Only about 25 malformed or missing genes stand between health and illness in Williams. That is 083% of the genes. It doesn't look like much .083%. Maybe a rounding error. But that tiny misquote in a string 30,000 genes long means:
Williams people talk a lot, and they talk with pretty much anyone. They appear to truly lack social fear. Indeed, functional brain scans have shown that the brain’s main fear processor, the amygdala, which in most of us shows heightened activity when we see angry or worried faces, shows no reaction when a person with Williams views such faces. It’s as if they see all faces as friendly.
They know no strangers but can claim few friends.
The brains of people with Williams are on average 15 percent smaller than normal, and almost all this size reduction comes from underdeveloped dorsal regions (along the back and the top of the brain) . Ventral regions (at the front and bottom), meanwhile, are close to normal and in some areas — auditory processing, for example — are unusually rich in synaptic connections
Generating and detecting deception and veiled meaning requires not just the recognition that people can be bad but a certain level of cognitive power that people with Williams typically lack. In particular it requires what psychologists call “theory of mind,” which is a clear concept of what another person is thinking and the recognition that the other person a) may see the world differently than you do and b) may actually be thinking something different from what he’s saying. Cognitive scientists argue over whether people with Williams have theory of mind.
I had been looking for a few days now for pictures of the very earliest embryonic development, that showed very early neural development. Thank you Institut National de Recherche Pédagogique.
This is what a human embryo looks like at three weeks. The disk itself is only a couple of cells thick. The black line over on the left there is wonderfully called the primitive streak.
- Courtesy of Institut National de Recherche Pédagogique
After the primitive streak fully forms, the neural tube begins to close. This picture is taken at about 22 days after fertilization.
- Courtesy of Institut National de Recherche Pédagogique
Something I've never really understood is how memories get stored. Unlike a hard drive, which I can picture physically holding a static image of a thought, experience, emotion or instructions for cleaning carburetors, living neurons "holding" onto anything baffles me.
I had thought I didn't understand biological memory because I didn't understand computer memory and programming. Which wouldn't be a surprise since I've never studied it. An electron goes to the left this time and to the right that time and that is why my wedding pictures are stored on my laptop. I have never really understood how you go from electrons going this way and that way in the physical world to software.
So when I saw this brief essayfrom the Edge, something was cleared up.
Joseph Ledoux is a professor of Neuroscience at NYU and the author of The Synaptic Self. The essay was his response to the annual World Question, which the Edge sends out to big brains the world over. In 2008 they asked "What have you changed your mind about?"
Ledoux wrote that he had changed his mind about how we remember, and his essay is also a primer on thinking scientifically -
Like many scientists in the field of memory, I used to think that a memory is something stored in the brain and then accessed when used.
Then, in 2000, a researcher in my lab, Karim Nader [showed] that each time a memory is used, it has to be restored as a new memory in order to be accessible later. The old memory is either not there or is inaccessible. [This is called] reconsolidation.
I'm not swayed by arguments based on faith, can be moved by good logic, but am always swayed by a good experiment, even if it goes against my scientific beliefs. I might not give up on a scientific belief after one experiment, but when the evidence mounts over multiple studies, I change my mind.
When evidence mounts, I change my mind
- From General Science written in 1912 in Philly!
Last time I wrote about consciousness, I was ruminating on how a near flip of a coin separates the wheat from the chaff, or in this case, the baby from the placenta. All cell's in a blastocyst have the potential to create consciousness, but only some are the progenitors of it.
When a cell is chosen for glory, that glory does not yet arrive. Consciousness is still down the road. But how far? When is an embryo sufficiently wired up with efficient neurons and synaptic density to make the transition from mere brain activity to consciousness?
Whatever consciousness is. So that's kind of a big bite to try and chew. Thankfully, lots of smart folks have been ruminating on this and are here to help.
Obviously there is a let-a hundred-flowers-bloom diversity of views on this. I'll focus on Prof Daniel Dennett's view now, and we'll get to differing views down the road a bit.
Professor Daniel Dennett of Tufts has been at the heart of an inquiring community developing a philosophical and biological theory of consciousness. A substantial number of smart people think Dennett's theory of consciousness is likely spot-on. This is his summary of his computational model -
At any given time, many modular cerebral networks are active in parallel and process information in an unconscious manner.
An information becomes conscious, however, if the neural population that represents it is mobilized by top-down attentional amplification into a brain-scale state of coherent activity that involves many neurons distributed throughout the brain. The long distance connectivity of these "workplace neurons" can... make the information available to a variety of processes including perceptual categorization, long-term memorization, evaluation, and intentional action.
We postulate that this global availability of information through the workplace is what we subjectively experience as a conscious state.
There is a backlog of posts sitting in the outbox awaiting some free time for final edits, but instead of tackling them, I want to lay out what lies ahead in the next 5 months for the Root System before the proto-human becomes the Kid
Part I.
My goal is to get a general, but complete, understanding of the brain functions that let each of us connect and root into the world. Which parts of the brain do what? Using what mechanisms? How does a single neuron work? How do neurons transfer information? How do they store information?
Part II.
As the Big Day gets closer, I'll start peering into the emotional and behavioral aspects of connection. When are the critical periods for learning different capabilities or developing certain interests? As the brain wires up, how do the emotional and experiential needs of the proto-human change? How can understanding what is happening in his/her brain help us understand and respond to the needs of the proto-human.
Part III.
Finally, there is the adventure itself. All the obsessed mucking about in neurons and glia and neurotransmitters can't hide that it is a real human being on its way, not a mechanical automaton driven by those chemical and electrical processes. And all the soaring meta talk can't resolve the urgent worry and eager anticipation I, we, feel.
At the end comes the unlearning, when the temptation to go all reductionist and mechanical fades. I am looking forward to those moments when the super-realistic details of parenthood shatter my simulated mastery and control.
Thanks for joining me.
When an egg is fertilized, a new cell is created with the combined genetic material of the father (me) and the mother (Mikaela). The newly formed zygote (from the Greek for "76 points in Scrabble" ) splits into many new yet identical cells until a small blackberry like glob of proto-human is floating it's way down to the uterus, inside its Zona Pellucida spaceship (marked one on the picture below.
-Image courtesy of the Swiss Virtual Campus
After five days of manufacturing genetically identical cells, differentiation begins at last. The cells on the outside of the blackberry, separate and form a globe (called the trophoblast). The inner-blackberry cells form a glob along one side of the dome (called the embryoblast)
-Image courtesy of the Swiss Virtual Campus
Those light blue cells become the placenta. The pea green cells the kid.
Of course biologists have shuffled the cells around right before segmentation, taking the inside cells destined for decades of greatness and shuffling them to the outside and taking the outside cells, destined for the brief and inglorious life of the placenta.
What happened to the potential for consciousness in those cells? Our existences are clearly contingent, from the very first moments when "your" sperm made it through "your" zona pellucida to this morning when you weren't creamed by MUNI on the way to work. One is the contingency of existence at all. The other is the contingency of existence continuing.
This is different from that familiar kind of contingency and I am fixated on it. The cells are identical in every way except their position relative to one another. Some become a human and some become an organ.
While the proto-human is a zygote, there is nothing we would call consciousness there, but potential is in every cell to create it. And when some of the cells drift one way and some of the cells drift another, there is still no consciousness. But there is a change.
In some cells there is still potential for consciousness while in others that door has closed. Actual consciousness is still many months away, but an irreversible, invisible and flip-of-the-coin lucky split in their fates sends one to life, the other to the mute darkness of a bladder or a fingernail.
This is a kind of contingency of potential. Coulda woulda shoulda, but wrong place, wrong time.
Next: So when does consciousness show up? Is it like a light switch or the lifting of fog?
And does the same thing happen in reverse as the work is undone? Do we diminish back into the fog, passing through the dimmer consciousness of the placenta before dissipating?
It felt like a kettle drum hit by a felt covered mallet.
It felt like a gentle rocking bump from passenger standing next to you on the subway.
It felt like touching a cheek flicked from the inside by a tongue.
It was round and soft and muffled, but urgent.
It was a reminder that life is restless, impatient, and eager.
There are some complicated concepts when you're reading about the brain. But sometimes the simplest things stand in your way.
For example, coronal and sagittal and axial just confused me. I kept forgetting which was which and what I had changed when I went from one to the other. Disorienting really.
So I looked them up and now I understand why I found it confusing. There are two reasons really.
First the definition of sagittal in the Houghton-Mifflin Medical Dictionary is
1. Of or relating to the suture uniting the two parietal bones of the skull.2. Of or relating to the sagittal plane.
Coronal: You're looking from the front or the back.
Sagittal: You're looking from the right side or the left side.
Axial: You're looking from above or below
It looks like the odds aren't great that there is intelligent life out there. Is there anybody out there? -
A mathematical model produced by Andrew Watson, Professor of Environmental Sciences at the University of East Anglia, suggests that the odds of finding new life on other Earth-like planets are low, given the time it has taken for beings such as humans to evolve and the remaining life span of the Earth.
[If] we had evolved early in this period, then even with a sample of one, we’d suspect that evolution from simple to complex and intelligent life was quite likely to occur. By contrast, we now believe that we evolved late in the habitable period, and this suggests that our evolution is rather unlikely. In fact, the timing of events is consistent with it being very rare indeed.”
Saw this article about why people turn down economically beneficial windfalls when they think they're being misteated. We talked about the irrationality of these decisions in upper-level economics classes a decade ago. Now those conversations are everywhere.
But this is interesting. From the article Are humans hardwired for fairness? in the journal Psychological Science. The Money Quote -
[T]he brain finds self-serving behavior emotionally unpleasant, but a different bundle of neurons also finds genuine fairness uplifting. What’s more, these emotional firings occur in brain structures that are fast and automatic, so it appears that the emotional brain is overruling the more deliberate, rational mind. Faced with a conflict, the brain’s default position is to demand a fair deal.
It may be possible to study brain formation not as a metaphor. Just the facts. But, boy, I sure find it hard.
The way your experiences carve your brain into a physical manifestation of those interactions seems to leave a lot of metaphors laying around to be stepped on.
Like, for example, the neuron that does not build strong connections dies. What happens to the kid who doesn't connect? As Passover approaches, I can't help but think that they live forever in the Narrows of limited experience.
So for example, a motor neuron dies if it doesn't connect to the muscle it is supposed to wire up. And that happens an awful lot. Between 40 and 75% of fetal neurons die.
Toe: stubbed.
The origin of the name dendrite from the good people at Scholarpedia -
The receiving or input pole [of the neuron] generally consists of extensively branching tree-like extensions of the soma membrane known as dendrites (coined in 1889 by William His from dendros (Greek) meaning tree) which arises in vertebrate neurons directly from the cell body (the body is also a receiving site in most neurons).
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