It looks to me as if you guys in here would have been so nice as to wait up for me - if so - thank you soo much - you are really sweet!
I want to apologize to yall for that - I am really sorry for bringing threads to a grinding halt like this.
So now I am back again - at least for now and hopefully for longer – I had a lot of free time on my hands – which is not exactly a bad thing – I got some amazing amount of fun things done – besides important things as well.
First of all - one of those fun things was following up on your two links Box77!
Unfortunately one doesn’t work – the meteor one. But the other does and it contains red-hot stuff I would say!
Once more:
A New Technique Could Erase Painful Memories -- Or Bring Them Back
Fascinating how much more fine-grained our understanding of memory is these days that such specific manipulations are possible! But it's pretty easy to get fantasies of mind-control and brainwashing like in the movies with on and off buttons here, too!
Okay – here goes – the usual – I indiscriminately suspect everybody including myself of laziness in clicking through:
A New Technique Could Erase Painful Memories -- Or Bring Them Back
By using pulses of light, researchers at the UC San Diego School of Medicine have produced, erased, and restored fearful memories in rats. It's a finding that could have profound implications for people struggling with neurodegenerative and anxiety disorders.
The study, though not the first to implant a memory in a rodent, is the first to selectively remove a memory — in this case, a conditioned fear response — and then predictably reactivate it by stimulating nerves in the brain at frequencies known to weaken and strengthen the connections between synapses. It's probably the most sophisticated memory engineering experiment done to date.
What's more, the study confirms a long-standing theory about how memories are made and stored in the brain. The experiment suggests that the weakening of specific nerve cells likely disassembles neuronal circuits, resulting in the inactivation of a memory. This confirmation hints at future therapies in which neuroscientists can take control of runaway emotional memories in mental illnesses, such as post-traumatic stress disorder.
Let There Be Light
Neuroscientists theorize that memories are formed when connections between neurons are strengthened — a process facilitated by mechanisms such as long-term potentiation (LTP) and long-term depression (LTD). But this has been difficult to demonstrate in the lab. This latest study, which was conducted by Roberto Malinow of the University of California, San Diego, Roger Tsien of NIH's National Institute on Neurological Disorders and Stroke (NINDS), and other UCSD colleagues, proves that a causal link exists between these synaptic processes.
It was a confirmation made possible by the burgeoning field of optogenetics — a technique in which a gene is delivered to the brain cell of an animal using a special virus. Once delivered, the gene produces a series of light-responsive proteins which can either be activated or disabled by fiber optic cables inserted into the brain. To date, neuroscientists have used the technique to induce sensations, memories, and behavioral changes in mice and monkeys. In the new experiment, pulses of fibre optic light were used to both remove and reactivate conditioned responses in rats.
Engineering Memory
The first stage of the experiment was to produce a conditioned fear response in the rats. The scientists did so by optically stimulating a group of nerves in rats' brains that had been genetically modified to make them sensitive to light. At the same time, the researchers delivered an electric shock to the rats' feet. The rats thus learned to associate the optical nerve stimulation with pain, thereby triggering fearful behavioral responses. Subsequent analysis showed that the resulting chemical changes were consistent with synaptic strengthening.
I wonder, what exactly they might mean by that - were they able to show that actual LTP or LTD (long term potentiating/depression on the level of synaptic micro-anatomy) has taken place? Which chemicals have they measured and where?
Following this stage, the scientists weakened this neural circuitry by stimulating the same batch of nerves with a memory-erasing, low frequency train of optical pulses. Following this, the rats no longer responded in a fearful way to the original nerve stimulation. The memory had, for all intents-and-purposes, been erased.
For the final and most astounding step, the neuroscientists restored the memory by re-stimulating the same nerves with the memory-forming, high-frequency train of optical pulses. Subsequent experiments shows that the rats were once again responding to the original stimulation with fear.
"We can cause an animal to have fear and then not have fear and then to have fear again by stimulating the nerves at frequencies that strengthen or weaken the synapses," noted lead author Sadegh Nabavi in a statement.
Looking to the future, and in addition to treating anxiety disorders, a similar technique could be used to treat age-related neurodegenerative diseases, such as Alzheimer's. But that's a far way's off; we still don't know how humans will respond to optogenetics. Moreover, for it to work in us humans, we'll have to be genetically modified to respond to the light in specific ways, and have the genes delivered to our brains via viruses. There's clearly a lot of work — and ethical objections — that still need to be overcome.
On my raid through Mr. Kurzweil’s wonderful transhumanism et cetera page – I came across something on memory formation, which doesn't equate with classical LTP:
Synchronized brain waves enable rapid learning | KurzweilAI
What they propose here, is that there is another, faster and more flexible way of learning besides or maybe prior to LTP/LTD. Which is long-term-potentiation/-depression on the level of micro-anatomy, actual synapses – what they talk about in Box77’s article for memory engineering. Especially categorical learning which is of a higher order than simple conditioned fear seems to be taking place in form of different brain areas synchronizing their firing rhythms. Before this learning takes place each of the areas only sings its own song:
Synchronized brain waves enable rapid learning
Why brain-wave resonance may be the key to learning, not synapses
MIT neuroscientists have found that as monkeys learn to categorize different patterns of dots, two brain areas involved in learning — the prefrontal cortex and the striatum — synchronize their brain waves to form new communication circuits.
“Category-learning results in new functional circuits between these two areas, and these functional circuits are rhythm-based, which is key because that’s a relatively new concept in systems neuroscience.”
There are millions of neurons in the brain, each producing its own electrical signals. These combined signals generate oscillations known as brain waves, which can be measured by electroencephalography (EEG). The research team focused on EEG patterns from the prefrontal cortex — the seat of the brain’s executive control system — and the striatum, which controls habit formation.
The phenomenon of brain-wave synchronization likely precedes the changes in synapses, or connections between neurons, believed to underlie learning and long-term memory formation, Miller says. That process, known as synaptic plasticity, is too time-consuming to account for the human mind’s flexibility, he believes.
“There’s got to be some way of dynamically establishing circuits to correspond to the thoughts we’re having in this moment, and then if we change our minds a moment later, those circuits break apart somehow. We think synchronized brain waves may be the way the brain does it.”
Humming together
Miller’s lab has previously shown that during category-learning, neurons in the striatum become active early, followed by slower activation of neurons in the prefrontal cortex. “The striatum learns very simple things really quickly, and then its output trains the prefrontal cortex to gradually pick up on the bigger picture,” Miller says
“The striatum learns the pieces of the puzzle, and then the prefrontal cortex puts the pieces of the puzzle together.”
This should cause some joy among those, who “always said it’s all about rhythm, waves and what have you”. Yupp – but you got to know, what you are talking about to make sense!
So – such a long post already – and I didn’t even answer your latest posts yet, Box77!
 Originally Posted by Box77
Steph: I know what you mean when you talk about your impressions in the Bus, right now I'm having that kind of impression (Not in a Bus ) that perhaps later I will remember with the same enthusiasm. The video you posted there, was something I wasn't able to find when I first read about optogenetics. Thanks for sharing! And your pics are very illustrative. It was something that used to happen with me during university (as long as I was able to tolerate their system) when studying Math and Physics, it was easier for me to understand some concepts with the graphics. By the way, now I understand why somebody told me that 'Pinky and the Brain' was not a joke.
Thank you!
 Originally Posted by StephL
Could it maybe be said, that evolution is responsible for the phenomenon, that the range of colour is the same for most of us creatures,
for all to see, so to speak?
Agreeing with each other on what to see?
Just a probably silly idea, before falling into bed, exhausted...
Doesn’t really make sense – at least not like this – I might start on over with it one day.
 Originally Posted by Box77
^^Apparently photo-receptors evolved from a cell which was sensitive to some range of electromagnetic waves which included the frequencies we are capable to see, like the range of blue for example.
Well, I would like to add a link I find interesting related to the process of evolution in order to guide other people interested in the subject from a scientific point of view and not necessarily skilled in the matters, like me and many others who I think, are willing to understand this little world around us just for curiosity and not by force:
Sharks' Sixth Sense Related to Human Genes
Short explanatory video about that 'sixth sense' here.
I would like to point out a paragraph from that article: "It still requires a definitive experiment, where the developing neural crest cells are marked with dye, the embryo develops and the dye clearly shows up in the electroreceptors"
Does anybody know if that "definitive experiment" already took place? That article dates from 2006. The one I found in National Geographic date back in 2010 but basically it says the same.
Very interesting! Thank you!!
Sharks can detect electricity and the below article says that probably a direct ancestor of ours with a spine could do that too. Genetic material pertaining to it is in the human genome, and plays a role in forming head and face features of ours.
There is a very attractive jump in reasoning, which could be made, but I guess they are not implying it with their experiment.
I think, they want to dye these neural crest cells in order to watch where they migrate and if the dye shows up in the electroreceptors.
Not in order to show how colour molecules could have found entry into such cells like suggested in the Sagan video - if you mean that?
He had his neural crest of electro-receptive cells and they came to contain "colour-molecules" - dye. If I remember this correctly now.
This is crucial to vision – you need a molecule, which is able to respond to light by changing molecular conformation and thus provide a signal, which can then be further processed.
They say there might be a connection to our sense of balance from the inner ear.
But who knows? Maybe they are the same cells, Sagan has been talking about anyway?
Now upon editing I am not entirely sure of some things actually... biggrin.gif
Soo – could we maybe get electro-receptivity back with retro-gene-engineering?!
It would only enable us to swim straight and other minor things I am afraid, though.
One more exhaustive quote - its exteeended discussion here after all and it’s interesting:
Sharks' Sixth Sense Related to Human Genes
Sharks' Sixth Sense Related to Human Genes
The same genes that give sharks their sixth sense and allow them to detect electrical signals are also responsible for the development of head and facial features in humans, a new study suggests.
The finding supports the idea that the early sea creatures which eventually evolved into humans could also sense electricity before they emerged onto land.
The study, led by Martin Cohn and his lab at the University of Florida, is detailed in the current issue of the journal Evolution & Development.
Sixth sense
Sharks have a network of special cells that can detect electricity, called electroreceptors, in their heads. They use them for hunting and navigation.
This sense is so developed that sharks can find fish hiding under sand by honing in on the weak electrical signals emitted by their twitching muscles.
The researchers examined embryos of the lesser spotted catshark. Using molecular tests, they found two independent genetic markers of neural crest cells in the sharks' electroreceptors. Neural crest cells are embryonic cells that pinch off early in development to form a variety of structures. In humans, these cells contribute to the formation of facial bones and teeth, among other things.
The finding suggests that neural crest cells migrate from the sharks' brains to various regions of the head, where they develop into electroreceptors.
Glenn Northcutt, a neuroscientist at the University of California, San Diego, who was not involved in the study, said the finding was interesting, but that more studies are needed before a direct link between neural crest cells and electroreceptors can be established.
"It still requires a definitive experiment, where the developing neural crest cells are marked with dye, the embryo develops and the dye clearly shows up in the electroreceptors," Northcutt said.
In the new study, the researchers found snippets of genetic material associated with neural crest cells in the electroreceptors. They did not dye the neural crest cells and trace their development.
Our electrical ancestors
Scientists think that all primitive animals with backbones, including the early ancestors of humans, could sense electricity. As they evolved, mammals, reptiles, birds and most fish lost the ability. Today, only sharks and a few other marine species, such as sturgeons and lampreys, can sense electricity.
"Our fishy ancestors had the anatomy for it," said study team member James Albert, a biologist from the University of Louisiana.
The ability to sense electrical signals is useful in aquatic environments because water is so conductive. On land, however, the sense is useless.
"Air doesn't conduct electricity as well," Albert said. "When it happens, it's called a lightning bolt and you don't need special receptors to sense it."
The development of the electroreceptors is believed to mirror the development of the lateral line, a sense organ in fish that allows them to detect motion in surrounding water. Similar processes are thought also to be involved in the development of the inner ear, the organs which help humans keep their balance.
The electroceptors are also believed to behind many sharks' ability to detect changes in the Earth's magnetic field. Other studies indicate that like sailors, sharks can also navigate by celestial cues.
Scientists think that these two abilities are what allow some sharks to swim straight lines across vast distances of featureless ocean. One recent study found that a great white shark, nicknamed Nicole, swam nearly 7,000 miles between South Africa and Australia in just under 100 days.
Thanks also for the video - I didn't watch it yet, though. But why oh why does it have to use the term Extrasensory Perception (ESP)?? It is clearly all about exactly and only sensory perception after all! And thank god for that! 
Is it to lure in otherwise unwilling audience? Well maybe then that’s okay - or so.
I have something sweet on “how evolution made us human” – comes later maybe.
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