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15

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 ...


11

I will just show the statistics of last attempt to mimic the brain process. Last year Japan launched there fastest supercomputer: 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 ...


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 ...


7

The temporal lobe is in the temporal region of the head, near the temples of the skull, hence the name. It's name does not relate to it's biological function, it is mainly involved in processing language, visual memories, and emotions. The medulla oblongata is one region of the brain that deals with a lot of the "tempo" type functions (tempo as in keeping ...


6

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 ...


5

One of the many advantage of an all-or-none system is that resources can be conserved for timing events that require synchronized collaboration between many cells (like locomotion). Binary behavior may also partially be a side effect of speed and efficient long-distance information transfer (which is one of the great advantages of neurons as cells in the ...


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

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 ...


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

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

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

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

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 ...


4

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 ...


3

Indeed, C. elegans nematodes (which are the ones you are talking about) do not show cognitive responses. AFAIK, Drosophila melanogaster is also able to learn and display some quite complex behaviors, but no cognitive functions. I believe the "simplest" organism known to display what could be called "cognitive" functions is the honeybee (see for example this ...


3

Auditory information is routed to cerebral hemispheres via the brainstem and midbrain. Structures in the midbrain receive information from both ears and combine it (including differencing it for spatial location) before sending the combined information on to both cerebral hemispheres. Usually only the left hemisphere interprets the sound for language ...


3

Electroencephalography has a good time resolution (milliseconds) but poor spatial resolution (several centimers). The usual estimated figure is that at least 50000 neurons need to fire simultaneously so that the activity can picked up by EEG. The answer provided by @Jeremy Kemball is not very accurate. The reason why the spatial resolution of EEG is poor is ...


3

I think that the advantages of using both hands with equal ease is quite evident whether it be sports, at your work or while you are doing your household chores. An obvious advantage is using both hands to write or draw with both at the same time. I would be focusing on the disadvantages that may be faced. 1) Ambidextrous people are more prone to ...


3

Only certain drugs can cross the blood brain barrier (BBB). However, there exist techniques to deliver drugs to the brain that otherwise cannot permeate through the BBB. One such technique is called intrathecal delivery that injects drugs directly into the cerebrospinal fluid, avoiding the BBB problem and allowing the drug to reach cells, including neurons, ...


3

Yes, they do. A blog post on the National Geographic website describes the results of a study about how blind people dream.(1) The participants who were born blind did not report any visual impressions. Among those who previously had sight, the number of visual impressions reported decreased with the time since loss of sight. Just as there are many ways ...


3

Crossing or decussation is a lot more robust against wiring errors than their seemingly simpler same-sided wiring counterparts. See here for the research carried out to establish this and for more detail.


3

Humans have evolved for 24 hour days and our bodies would not adapt well to this short of sleep/wake cycles (whether or not they were born there, unless they have been there for many generations and have been able to evolve for the new time). Our bodies would still want to spend about the same amount of time sleeping and being awake. If we tried to adjust ...


3

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, ...


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

This is a hard question to respond to. Many things might make someone grumpy. There are also individual temperaments, making grumpy hard to quantify - a Grumpy to one person might barely be a blip on another individual's scale. Hormones like cortisol reflect stress, and can make people in general irritable, but I doubt any one combination of hormones ...


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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