Of course we would like a system (or anti-system), where nobody does evil things, but I see no evidence that such a thing is possible. A well-functioning state seems to be the system that minimizes the amount of evil that is allowed to happen.
AFAICT, a state is like an organized crime syndicate with some level of accountability to its victims, or a feudal organization with some accountability to its subjects. Since these sorts of organizations always seem to pop up in the absence of a state, I would much rather keep a system with imperfect accountability than make room for a system with no accountability.
I always feel like I'm struggling to make a very simple and obvious point on this subject. Perhaps I should read more of James Madison's writings, since he seems to have covered much of the same ground, and he was a manifestly more persuasive writer than I am.
I really want an excuse for Daft Punk to do another epic soundtrack. Tron Legacy is pretty weak as a narrative, but it's fantastic if you think of it as an extended Daft Punk music video.
How does long-term memory work? It involves many changes in your brain, from changes in how strongly individual neurons talk to each other, to the actual birth of new neurons. But one fascinating possibility involves the DNA in your neurons!
See those glowing dots? Those are methyl groups, consisting of a carbon and 3 hydrogens. They can attach to certain locations in your DNA and prevent genes from being expressed. This is called DNA methylation, and it's important part of the system you use to turn genes on and off.
These methyl groups can even be transmitted from parent to child! For example: if you are hungry for much of your life, your body will adapt, using DNA methylation — and your children can inherit these adaptations. This will make them more likely to become obese if they get as much food as they want.
All this makes evolution more interesting than people had thought. We can inherit traits our parents acquired during their lives!
Given all this, it's natural to ask: does DNA methylation play a role in memory?
There are hints that the answer is yes. For example, scientists gave some mice an electric shock and others not. They looked at whether a specific gene in their neurons was methylated. It was more methylated in the shocked mice... and this lasted for at least 30 days.
What was this gene? It's the gene for a protein called calcineurin, which is thought to be a 'memory suppressor'. More precisely, calcineurin tends to prevent the neurons from forming stronger connections between each other.
So: the mice responded to an electric shock by attaching methyl groups to their DNA. This reduced the production of calcineurin, which tends to prevent the brain from forming new connections!
So, their brains could more easily build new connections.
And all this happened in a specific location of the brain: the anterior cingulate cortex, which is important for rational thinking in humans, and something similar in mice.
This is just one of many experiments people are doing to understand the role of DNA methylation in memory. And DNA methylation is just one of the ways a cell can regulate which of its genes get expressed! There's a field called epigenetics, which is all about these control systems.
You could say that epigenetics is a way for cells to learn things during their lives. When you move to a hot climate, and then your body "gets used to" the heat — sweating less and so on — that's epigenetics at work. So, maybe it's not surprising that epigenetics is also important for how the brain learns things.
Here's a nice article on the role of epigenetics in memory:
and here's one about the role of DNA methylation:
• Jeremy J. Day and J. David Sweatt, DNA methylation and memory formation, Nature Neuroscience 13 (2010), 1319–1323. Available for free at http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3130618/
The experiment I described is here:
• Courtney A. Miller et al, Cortical DNA methylation maintains remote memory, Nature Neuroscience 13 (2010), 664–666. Available for free at http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3043549/
If you want to learn more about how epigenetics can pass information from one generation to the next, start here:
A nice quote from Joseph Springer and Dennis Holley's book An Introduction to Zoology:
Lamarck and his ideas were ridiculed and discredited. In a strange twist of fate, Lamarck may have the last laugh. Epigenetics, an emerging field of genetics, has shown that Lamarck may have been at least partially correct all along. It seems that reversible and heritable changes can occur without a change in DNA sequence (genotype) and that such changes may be induced spontaneously or in response to environmental factors - Lamarck's "acquired traits". Determining which observed phenotypes are genetically inherited and which are environmentally induced remains an important and ongoing part of the study of genetics, developmental biology, and medicine.
There's a huge amount of stuff to learn in these areas, and it's pretty intimidating to me, since I'm just getting started, and it will probably never be more than a hobby. Changes in how strongly individual neurons talk to each other are called synaptic plasticity:
These include long-term potentiation, meaning ways that two neurons can become more strongly connected:
and also long-term depression, where they become less strongly connected:
A basic rule of thumb is that "neurons that fire together, wire together". But there's a lot more going on....
#spnetwork doi:10.1038/nn.2560 #epigenetics #memory
The prison strike leaders are denied televisions and reading material. They spend at least three days a week, sometimes longer, without leaving their tiny isolation cells. They eat their meals seated on their steel toilets. They are allowed to shower only once every two days despite temperatures that routinely rise above 90 degrees.
The men have become symbols of a growing resistance movement inside American prisons. The prisoners’ work stoppages and refusal to co-operate with authorities in Alabama are modeled on actions that shook the Georgia prison system in December 2010. The strike leaders argue that this is the only mechanism left to the 2.3 million prisoners across America. By refusing to work—a tactic that would force prison authorities to hire compensated labor or to induce the prisoners to return to their jobs by paying a fair wage—the neoslavery that defines the prison system can be broken. Prisoners are currently organizing in Arizona, California, Florida, Illinois, Ohio, Pennsylvania, Mississippi, Texas, Virginia and Washington.
For the last few weeks, Googlers have been obsessed with an internal visualization tool that Alexander Mordvintsev in our Zurich office created to help us visually understand some of the things happening inside our deep neural networks for computer vision. The tool essentially starts with an image, runs the model forwards and backwards, and then makes adjustments to the starting image in weird and magnificent ways.
In the same way that when you are staring at clouds, and you can convince yourself that some part of the cloud looks like a head, maybe with some ears, and then your mind starts to reinforce that opinion, by seeing even more parts that fit that story ("wow, now I even see arms and a leg!"), the optimization process works in a similar manner, reinforcing what it thinks it is seeing. Since the model is very deep, we can tap into it at various levels and get all kinds of remarkable effects.
Alexander, , and Mike Tyka wrote up a very nice blog post describing how this works:
There's also a bigger album of more of these pictures linked from the blog post:
I just picked a few of my favorites here.
Clinton/Sanders will win. No question. And they'll make a great team. You can put money on this. Barring some miracle involving the Republicans having 2 or 3 good candidates instead of 50 horrible ones.
Only circling people who post in English mostly works, but those pesky multilingual people sometimes post in other languages.
I just got Distant Worlds: Universe, and I realized it wasn't going to be good for me when I saw in the preferences that it auto-saves your game every half hour by default. This seems to imply an average session is several hours long, and I don't have nearly the patience for that. I want to be entertained in short bursts. I guess that means I've become a "casual" gamer.
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