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16

No, it can't be done for a lot of reasons. Here are just a few. 1) Memories are stored in electrical pathways, not the the cells themselves. You don't have 1000 memories in a chunk of brain that contains 1000 neurons. If you don't get the entire pathway, you won't get the memory. 2) Once a nerve is cut, it won't fuse with another cut nerve. All you'll have ...


15

I will just show the statistics of last attempt to mimic the brain process. In 2011 fastest computer in Japan was launched: K computer OR SPARC64 VIIIfx 2.0GHz Features: Manufacturer: Fujitsu Cores: 705,024 Linpack Performance (Rmax) 10,510 TFlop/s Theoretical Peak (Rpeak) 11,280.4 TFlop/s Power: 12,659.89 kW Memory: 1,410,048 GB (16GB RAM ...


11

Is there a significant difference in calorie burn? No. The brain, while only making up 2% of our body weight, accounts for ~20% of our energy use at rest. That's because the brain, being critical for survival, is a very high-maintenance organ. At rest, the membrane potentials of all neurons - firing or at "rest" - need to be controlled/maintained. Of ...


10

First of all, I would like to point out that making analogy between digital computers and the brain is often very misleading. That being said, my answer is, some scientists believe so, some don't. Several things to consider: Some neural systems are not spiking. C. elegans for example has a nervous system that is entirely analogue. Human nervous system ...


9

There's a very big difference between doing the calculations needed to simulate the human brain (or any animal brain FTM - we can do a fairly decent job on C. elegans.), and doing computations. While a basic leaky integrate & fire model is fairly simple, to ACCURATELY simulate a single neuron in real time takes a pretty fast computer. See e.g. these ...


8

I think I can partially answer you question. As far as I'm aware, there are many surface receptor molecules such as ephrins that are responsible for axonal guidance and dendritic repulsion in developing organisms such as flies (Drosophila). As you can tell this is extremely crucial since its important for neurons to spread their dendrites and axons as far as ...


8

Short answer: no, there is no fixed frame rate or frame-based processing in mammalian vision. Photons arriving at the photoreceptors at the back of the human retina interact with photo-sensitive pigments called opsins, and modulate their release of the neurotransmitter glutamate . The level of glutamate released from a photoreceptor then changes the ...


8

Short answer The exact mechanism behind tinnitus (ringing in the ear) is unknown. Background Of the two theories you pose here, to the best of my knowledge the second one is the most widely accepted. It is a generally accepted phenomenon that whenever neural systems are being deprived of input, they start seeking new input, or even generate it ...


7

Three possible mechanisms are mentioned in the first referenced article [1]: Attentional blink - the failure to detect a (visual) stimulus [2]. Visual short-term memory - non-permanent storage of visual information over an extended period of time [3]. Psychological refractory period - the period of time during which the response to a second stimulus is ...


6

It's very likely that memory is "lossy" and holographic, such that you can keep adding more information indefinitely, but retain it with less and less accuracy. Memory isn't a digital storage system with X gigabytes of capacity, and the inputs to memory aren't neat little packets. What we remember are a web of associations and patterns. Vastly ...


6

http://en.wikipedia.org/wiki/Electromagnetic_pulse mentions the following natural sources of EMP, which I have ordered by frequency / period, from the shortest to the longest: Electrostatic discharge from objects coming into contact (normally too small to be of any concern) Lightning (milliseconds) Solar flares (hours.) Such flares cause geomagnetic storms ...


6

If firing rate is from 1 Hz to 200 Hz, 100 trillion to 20 quadrillion synaptic firings. Neuronal (say, measured from soma) firings will add up to 86 billion to 17.2 trillion action potentials per second. It important to remember, that synaptic firings "sum up" in soma or interfere between each other, so the are more of those. Read more: ...


5

The recurrent patterns of connections in a network are known as network motifs. You can check this paper out. They have identified common network motifs in different types of real networks including neural networks (of C.elegans though). Apart from feed forward loops, bi-fan is also a common network motif in neural networks. Perhaps the connectome ...


5

Is there a visual demonstration I can see of approximately how "packed full of cells" the brain actually is? Yes. You can inject tracers in the CSF (Cerebrospinal fluid) or in the ventricles and monitor them. In this study, the authors have injected a fluorescent tracer in the CSF and used a direct imaging. We used in vivo two-photon imaging to ...


5

While action potentials are usually binary, you should note that synaptic communication between neurons is generally not binary. Most synapses work by neurotransmittors, and this is a chemically mediated graded response that, for example, act on voltage-gated ion channels. So even though action potentials are often binary, communication between neurons are ...


5

The "wiring" of the brain is more important than the actual size. If only size would matter that basically humans would be rather unintelligent beings ( many many animals have larger head and brain than us). Intelligence is more related to the complexity of the brain (number and size of different brain components) and the number of connections between ...


5

I did a quick search and found some research in this area. Sleep inertia is the technical term for feeling groggy for a while after waking up. In a review article by Patricia Tassi, Alain Muzet (Sleep inertia. Sleep Medicine Reviews. Volume 4, Issue 4, August 2000, Pages 341–353), they define sleep inertia as Sleep inertia is a transitional state of ...


4

In cases of severe head injury where a large portion of neurons and their connections get shredded. I don't think a neuron would be very choosy when presented with quite a few axons and lots of intracellular fluid There are coup and the contra coup (p silent) brain injuries that occur because the brain bounces back and forth in the skull. The contra coup, ...


4

Yes, there is a limit: Despite the impressive complexity and processing power of the human brain, it is severely capacity limited [1]. Human brain has 78.82– 95.40 billion neurons [2] and about $3.6 \cdot 10^{14}$ synapses in the cortex [3]. We shouldn't worry about running out of space, because neurons connect with each other to exponentially increase ...


4

Yes, but rarely. Other types of brain cells are much more likely to form tumors. Oligodendrocytes, astrocytes, and more generally glial cells all form tumors with some regularity. Nerve sheaths can also form benign growths. Nerves themselves can even manifest cancerous behavior, even though they are nearly always benign and very slow growing. ...


4

Having just read this article (http://www.ncbi.nlm.nih.gov/books/NBK11164/) there are several advantages/functional reasons that seem apparent and important in having electrical synapses with gap junctions compared to just a very long neuron. a) signals in electrical synapse can be bidirectional. b) electrical synapse synchronize electrical activity among ...


4

There are an estimated 100 billion neurons within the human brain. In general a minor variation in the number of neurons should not effect individuals too much, however when there is a more significant loss, such as brain injury or in some forms of dementia cognitive abilities do decline. So in this sense yes the number of neurons does relate to ...


4

Neuroscience doesn't really have a clear model for what a "thought" consists of exactly. Certain processes that are involved in thought have begun to be mapped--for example, this recent paper talks about a model for how the brain associates location in space with it's own mental map (http://www.ncbi.nlm.nih.gov/pubmed/24462102, I'll try to find something ...


4

Misophonia Misophonia is a relatively unexplored chronic condition in which a person experiences autonomic arousal (analogous to an involuntary “fight-or-flight” response) to certain innocuous or repetitive sounds such as chewing, pen clicking, and lip smacking. Misophonics report anxiety, panic, and rage when exposed to trigger sounds, ...


4

The brain is not an electronic device. An EMP is basically a large amount of electrons flying by all at once. They are negatively charged, and as they pass by they distort your local EM-field (hence the name). This distortion induces current in the wires (a phenomenon known since Faraday) - since most wires aren't made with a large tolerance, the sudden ...


4

Human body is a glucose driven machine which intake carbohydrates and converts to glucose. Energy is yielded from the glucose and glucose is stored as glycogen. When the carbohydrate intake is somehow reduced then body will shift its mechanism and uses the fatty acids to produce energy. Liver synthesis ketones from fatty acids in our diet or from body fat. ...


3

I know of no correlation between number of neurons in cortex and intelligence. This question is fraught with controversy because there has been very little work on it but much speculation. Some have suggested that the connectivity between neurons is what is important rather than the number which is logically possible but remains to be supported by definitive ...


3

The myelin sheath of a neuron affects conduction of action potentials. Things to read through at wikipedia for example are the Nodes of Ranvier, the saltatory conduction and the Schwann cells. There might be other features changing nervous conduction, but those are the ones I remember from my study times.


3

Ok, let's talk about mammalian neocortex rather than about the entire central nervous system. The vast majority of synapses within the cortex are formed between neurons within the same cortical area (Binzegger et al 2004). Although most of these synapses will not be self-connections (from a single neuron back to itself), they are recurrent in the sense that ...


3

There are multiple levels of memory, some of which would die immediately, some of which would take some time. So the answer is: it depends; some immediately, some only very slowly. At the highest level, the current neuronal firing state of the brain encodes memory on a very short scale - working memory. The memory held on this level does not have a clear ...



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