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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 ...


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I assume with EM you refer to electromagnetic? You are right that the EEG (electroencephalogram) is a tiny signal. When about 50.000 neurons fire simultaneously, it possible to see a change in the measured signal. Typical EEG amplitudes are in the microvolt range. Now, when the EEG is recorded, it is a function of time. You could for example collect data ...


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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 ...


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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 ...


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The biological part of the answer to your question depends on the thing causing the pain. Burning for example, a large burn can be very life threatening biologically but small burns are not as harmful comparatively. But the psychological harm they would cause is phenomenal. This is because large burns open up the body to infections, dehydration and a lot of ...


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According to this page the release of DMT upon death is speculative and its presence has so far been confirmed in rodents brain and human melanoma cell line SK-Mel-147. DMT is also produced in humans; however, its production and purpose in the brain has yet to be proven or understood (http://en.wikipedia.org/wiki/Dimethyltryptamine). Hence from what I have ...


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It's important to clarify what an EEG machine measures. Electromagnetic waves are photons. An EEG does does not detect radiation. It detects magnetic fields by measuring an electrical current induced in the measuring device by the brain. Electricity is the movement of electrons. Electromagnetic waves are photons of light. Magnetism a force which fills ...


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While in human made cameras light sensor and any image processor are separate devices, in the living eye the first steps image analysis begin in retina already as light sensing cells are part of the nervous system. The optic nerve carries pre-processed information and not the encoded original image to the brain. This pre-processed information is not ...


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Unlike a computer, the speed at which any brain can perform a computation is related to the number of synapses it goes through. This means fewer synapses in series correlate with decreased reaction time. An example of fewer neurons correlating with a decrease in reaction time is exemplified in sensory neurons. All sensory nerve cell bodies are all located ...


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there is no question there is a rough correlation between neuron count and intelligence capability in a general way from looking at the biological species "spectrum" outside of humans. see wikipedia list of animals by number of neurons. eg in wide differences such as comparing insects vs primates etcetera. there is also a rough correlation of neuron count ...


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The use of spikes is a mixture of their computational advantages and the limitations of the biological substrate in which they are implemented: They can travel long distances at high speeds because they can profit from the saltatory conduction which is much faster than diffusion and it can be maintained over long distances. A digital signal is less prone ...


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The brain is separated into different regions, and different regions perform different tasks Not really. This kind of claims stem from the early brain research, where every area was thought to specialize in one particular task. Sure, some categorization is possible (e.g. where the visual input is mostly processed). However, your question is basically an ...


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We don't know yet in detail how different cortical areas are wired up, so it's difficult to say to what extent the wiring differs. But the overall structure of different cortical areas is remarkably similar, in terms of the layers of cortex and their cellular components. Certainly the structure of the input is very different between cortical areas, and ...


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It's for control, coordination and balance. From a mathematical point of view, parallel lines won't intersect and thus line A won't affect line B unless they intersect and thus would hardly influence the other unless and an external force is applied to any of the lines. This is also why corpus callosum connects the left and the right side of the brain.



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